text: /*
   * GStreamer
   *
   * Copyright (C) 2012 Cisco Systems, Inc.
   *   Author: Youness Alaoui <youness.alaoui@collabora.co.uk>
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Library General Public
   * License as published by the Free Software Foundation; either
   * version 2 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Library General Public License for more details.
   *
   * You should have received a copy of the GNU Library General Public
   * License along with this library; if not, write to the
   * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
   * Boston, MA 02110-1301, USA.
   */
  
  
  /**
   * SECTION:element-uvch264-src
   * @title: uvch264-src
   *
   * A camera bin src element that wraps v4l2src and implements UVC H264
   * Extension Units (XU) to control the H264 encoder in the camera
   */
  
  #ifdef HAVE_CONFIG_H
  #include <config.h>
  #endif
  
  #include "gstuvch264_src.h"
  
  #include <gst/video/video.h>
  #include <linux/uvcvideo.h>
  #include <linux/usb/video.h>
  #include <sys/ioctl.h>
  #include <string.h>
  
  #include "gstuvch264_src.h"
  #include <gudev/gudev.h>
  #include <libusb.h>
  #ifndef LIBUSB_CLASS_VIDEO
  #define LIBUSB_CLASS_VIDEO 0x0e
  #endif
  
  typedef struct
  {
    int8_t bLength;
    int8_t bDescriptorType;
    int8_t bDescriptorSubType;
    int8_t bUnitID;
    uint8_t guidExtensionCode[16];
  } __attribute__ ((__packed__)) xu_descriptor;
  
  #define GUID_FORMAT "02X%02X%02X%02X-%02X%02X%02X%02X-"\
    "%02X%02X%02X%02X-%02X%02X%02X%02X"
  #define GUID_ARGS(guid) guid[0], guid[1], guid[2], guid[3],       \
      guid[4], guid[5], guid[6], guid[7],                           \
      guid[8], guid[9], guid[10], guid[11],                         \
      guid[12], guid[13], guid[14], guid[15]
  
  #define USB_VIDEO_CONTROL		1
  #define USB_VIDEO_CONTROL_INTERFACE	0x24
  #define USB_VIDEO_CONTROL_XU_TYPE	0x06
  
  enum
  {
    PROP_0,
    /* uvch264_src properties */
    PROP_COLORSPACE_NAME,
    PROP_JPEG_DECODER_NAME,
    PROP_NUM_CLOCK_SAMPLES,
    /* v4l2src properties */
    PROP_NUM_BUFFERS,
    PROP_DEVICE,
    PROP_DEVICE_NAME,
    /* Static controls */
    PROP_INITIAL_BITRATE,
    PROP_SLICE_UNITS,
    PROP_SLICE_MODE,
    PROP_IFRAME_PERIOD,
    PROP_USAGE_TYPE,
    PROP_ENTROPY,
    PROP_ENABLE_SEI,
    PROP_NUM_REORDER_FRAMES,
    PROP_PREVIEW_FLIPPED,
    PROP_LEAKY_BUCKET_SIZE,
    /* Dynamic controls */
    PROP_RATE_CONTROL,
    PROP_FIXED_FRAMERATE,
    PROP_MAX_MBPS,                /* read-only */
    PROP_LEVEL_IDC,
    PROP_PEAK_BITRATE,
    PROP_AVERAGE_BITRATE,
    PROP_MIN_IFRAME_QP,
    PROP_MAX_IFRAME_QP,
    PROP_MIN_PFRAME_QP,
    PROP_MAX_PFRAME_QP,
    PROP_MIN_BFRAME_QP,
    PROP_MAX_BFRAME_QP,
    PROP_LTR_BUFFER_SIZE,
    PROP_LTR_ENCODER_CONTROL,
  };
  /* In caps : frame interval (fps), width, height, profile, mux */
  /* Ignored: temporal, spatial, SNR, MVC views, version, reset */
  /* Events: LTR, generate IDR */
  
  enum
  {
    /* action signals */
    SIGNAL_GET_ENUM_SETTING,
    SIGNAL_GET_BOOLEAN_SETTING,
    SIGNAL_GET_INT_SETTING,
    LAST_SIGNAL
  };
  
  static guint _signals[LAST_SIGNAL];
  
  /* Default values */
  #define DEFAULT_COLORSPACE_NAME "videoconvert"
  #define DEFAULT_JPEG_DECODER_NAME "jpegdec"
  #define DEFAULT_NUM_CLOCK_SAMPLES 0
  #define DEFAULT_NUM_BUFFERS -1
  #define DEFAULT_DEVICE "/dev/video0"
  #define DEFAULT_DEVICE_NAME NULL
  #define DEFAULT_INITIAL_BITRATE 3000000
  #define DEFAULT_SLICE_UNITS 4
  #define DEFAULT_SLICE_MODE UVC_H264_SLICEMODE_SLICEPERFRAME
  #define DEFAULT_IFRAME_PERIOD 10000
  #define DEFAULT_USAGE_TYPE UVC_H264_USAGETYPE_REALTIME
  #define DEFAULT_ENTROPY UVC_H264_ENTROPY_CAVLC
  #define DEFAULT_ENABLE_SEI FALSE
  #define DEFAULT_NUM_REORDER_FRAMES 0
  #define DEFAULT_PREVIEW_FLIPPED FALSE
  #define DEFAULT_LEAKY_BUCKET_SIZE 1000
  #define DEFAULT_RATE_CONTROL UVC_H264_RATECONTROL_CBR
  #define DEFAULT_FIXED_FRAMERATE FALSE
  #define DEFAULT_LEVEL_IDC 40
  #define DEFAULT_PEAK_BITRATE DEFAULT_INITIAL_BITRATE
  #define DEFAULT_AVERAGE_BITRATE DEFAULT_INITIAL_BITRATE
  #define DEFAULT_MIN_QP 10
  #define DEFAULT_MAX_QP 46
  #define DEFAULT_LTR_BUFFER_SIZE 0
  #define DEFAULT_LTR_ENCODER_CONTROL 0
  
  #define NSEC_PER_SEC (G_USEC_PER_SEC * 1000)
  
  
  GST_DEBUG_CATEGORY (uvc_h264_src_debug);
  #define GST_CAT_DEFAULT uvc_h264_src_debug
  
  #define gst_uvc_h264_src_parent_class parent_class
  G_DEFINE_TYPE (GstUvcH264Src, gst_uvc_h264_src, GST_TYPE_BASE_CAMERA_SRC);
  
  #define GST_UVC_H264_SRC_VF_CAPS_STR \
    GST_VIDEO_CAPS_MAKE (GST_VIDEO_FORMATS_ALL) ";" \
    "image/jpeg,"                                   \
    "width = " GST_VIDEO_SIZE_RANGE ","             \
    "height = " GST_VIDEO_SIZE_RANGE ","            \
    "framerate = " GST_VIDEO_FPS_RANGE
  
  #define GST_UVC_H264_SRC_VID_CAPS_STR                                   \
    GST_UVC_H264_SRC_VF_CAPS_STR ";"                                      \
    "video/x-h264, "                                                      \
    "width = " GST_VIDEO_SIZE_RANGE ", "                                  \
    "height = " GST_VIDEO_SIZE_RANGE ", "                                 \
    "framerate = " GST_VIDEO_FPS_RANGE ", "                               \
    "stream-format = (string) { byte-stream, avc }, "                     \
    "alignment = (string) au, "                                           \
    "profile = (string) { high, main, baseline, constrained-baseline }"
  
  static GstStaticPadTemplate vfsrc_template =
  GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_VIEWFINDER_PAD_NAME,
      GST_PAD_SRC,
      GST_PAD_ALWAYS,
      GST_STATIC_CAPS (GST_UVC_H264_SRC_VF_CAPS_STR));
  
  static GstStaticPadTemplate imgsrc_template =
  GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_IMAGE_PAD_NAME,
      GST_PAD_SRC,
      GST_PAD_ALWAYS,
      GST_STATIC_CAPS_NONE);
  
  static GstStaticPadTemplate vidsrc_template =
  GST_STATIC_PAD_TEMPLATE (GST_BASE_CAMERA_SRC_VIDEO_PAD_NAME,
      GST_PAD_SRC,
      GST_PAD_ALWAYS,
      GST_STATIC_CAPS (GST_UVC_H264_SRC_VID_CAPS_STR));
  
  
  static void gst_uvc_h264_src_dispose (GObject * object);
  static void gst_uvc_h264_src_set_property (GObject * object,
      guint prop_id, const GValue * value, GParamSpec * pspec);
  static void gst_uvc_h264_src_get_property (GObject * object,
      guint prop_id, GValue * value, GParamSpec * pspec);
  static gboolean gst_uvc_h264_src_event (GstPad * pad, GstObject * parent,
      GstEvent * event);
  static gboolean gst_uvc_h264_src_send_event (GstElement * element,
      GstEvent * event);
  static gboolean gst_uvc_h264_src_construct_pipeline (GstBaseCameraSrc *
      bcamsrc);
  static gboolean gst_uvc_h264_src_set_mode (GstBaseCameraSrc * bcamsrc,
      GstCameraBinMode mode);
  static gboolean gst_uvc_h264_src_start_capture (GstBaseCameraSrc * camerasrc);
  static void gst_uvc_h264_src_stop_capture (GstBaseCameraSrc * camerasrc);
  static GstStateChangeReturn gst_uvc_h264_src_change_state (GstElement * element,
      GstStateChange trans);
  static GstPadProbeReturn gst_uvc_h264_src_buffer_probe (GstPad * pad,
      GstPadProbeInfo * info, gpointer user_data);
  static GstPadProbeReturn gst_uvc_h264_src_event_probe (GstPad * pad,
      GstPadProbeInfo * info, gpointer user_data);
  static void gst_uvc_h264_src_pad_linking_cb (GstPad * pad,
      GstPad * peer, gpointer user_data);
  static gboolean gst_uvc_h264_src_query (GstPad * pad, GstObject * parent,
      GstQuery * query);
  
  
  static void v4l2src_prepare_format (GstElement * v4l2src, gint fd,
      GstCaps * caps, gpointer user_data);
  static void fill_probe_commit (GstUvcH264Src * self,
      uvcx_video_config_probe_commit_t * probe, guint32 frame_interval,
      guint32 width, guint32 height, guint32 profile,
      UvcH264StreamFormat stream_format);
  static gboolean xu_query (GstUvcH264Src * self, guint selector, guint query,
      guchar * data);
  
  static void set_rate_control (GstUvcH264Src * self);
  static void set_level_idc (GstUvcH264Src * self);
  static void set_bitrate (GstUvcH264Src * self);
  static void set_qp (GstUvcH264Src * self, gint type);
  static void set_ltr (GstUvcH264Src * self);
  static void update_rate_control (GstUvcH264Src * self);
  static guint32 update_level_idc_and_get_max_mbps (GstUvcH264Src * self);
  static void update_bitrate (GstUvcH264Src * self);
  static gboolean update_qp (GstUvcH264Src * self, gint type);
  static void update_ltr (GstUvcH264Src * self);
  
  static gboolean gst_uvc_h264_src_get_enum_setting (GstUvcH264Src * self,
      gchar * property, gint * mask, gint * default_value);
  static gboolean gst_uvc_h264_src_get_boolean_setting (GstUvcH264Src * self,
      gchar * property, gboolean * changeable, gboolean * def);
  static gboolean gst_uvc_h264_src_get_int_setting (GstUvcH264Src * self,
      gchar * property, gint * min, gint * def, gint * max);
  
  static void
  gst_uvc_h264_src_class_init (GstUvcH264SrcClass * klass)
  {
    GObjectClass *gobject_class;
    GstElementClass *gstelement_class;
    GstBaseCameraSrcClass *gstbasecamerasrc_class;
  
    parent_class = g_type_class_peek_parent (klass);
  
    gobject_class = G_OBJECT_CLASS (klass);
    gstelement_class = GST_ELEMENT_CLASS (klass);
    gstbasecamerasrc_class = GST_BASE_CAMERA_SRC_CLASS (klass);
  
    gobject_class->dispose = gst_uvc_h264_src_dispose;
    gobject_class->set_property = gst_uvc_h264_src_set_property;
    gobject_class->get_property = gst_uvc_h264_src_get_property;
  
    gstelement_class->change_state = gst_uvc_h264_src_change_state;
    gstelement_class->send_event = gst_uvc_h264_src_send_event;
  
    gstbasecamerasrc_class->construct_pipeline =
        gst_uvc_h264_src_construct_pipeline;
    gstbasecamerasrc_class->set_mode = gst_uvc_h264_src_set_mode;
    gstbasecamerasrc_class->start_capture = gst_uvc_h264_src_start_capture;
    gstbasecamerasrc_class->stop_capture = gst_uvc_h264_src_stop_capture;
  
    GST_DEBUG_CATEGORY_INIT (uvc_h264_src_debug, "uvch264src",
        0, "UVC H264 Compliant camera bin source");
  
    gst_element_class_set_static_metadata (gstelement_class,
        "UVC H264 Source",
        "Source/Video",
        "UVC H264 Encoding camera source",
        "Youness Alaoui <youness.alaoui@collabora.co.uk>");
  
    gst_element_class_add_static_pad_template (gstelement_class,
        &vidsrc_template);
    gst_element_class_add_static_pad_template (gstelement_class,
        &imgsrc_template);
    gst_element_class_add_static_pad_template (gstelement_class, &vfsrc_template);
  
    /* Properties */
    g_object_class_install_property (gobject_class, PROP_COLORSPACE_NAME,
        g_param_spec_string ("colorspace-name", "colorspace element name",
            "The name of the colorspace element",
            DEFAULT_COLORSPACE_NAME, G_PARAM_CONSTRUCT | G_PARAM_READWRITE |
            GST_PARAM_MUTABLE_READY | G_PARAM_STATIC_STRINGS));
    g_object_class_install_property (gobject_class, PROP_JPEG_DECODER_NAME,
        g_param_spec_string ("jpeg-decoder-name", "jpeg decoder element name",
            "The name of the jpeg decoder element",
            DEFAULT_JPEG_DECODER_NAME, G_PARAM_CONSTRUCT | G_PARAM_READWRITE |
            GST_PARAM_MUTABLE_READY | G_PARAM_STATIC_STRINGS));
  
    g_object_class_install_property (gobject_class, PROP_NUM_CLOCK_SAMPLES,
        g_param_spec_int ("num-clock-samples", "num-clock-samples",
            "Number of clock samples to gather for the PTS synchronization"
            " (-1 = unlimited)",
            0, G_MAXINT, DEFAULT_NUM_CLOCK_SAMPLES,
            G_PARAM_READWRITE | G_PARAM_CONSTRUCT | GST_PARAM_MUTABLE_PLAYING |
            G_PARAM_STATIC_STRINGS));
  
    /* v4l2src proxied properties */
    g_object_class_install_property (gobject_class, PROP_NUM_BUFFERS,
        g_param_spec_int ("num-buffers", "num-buffers",
            "Number of buffers to output before sending EOS (-1 = unlimited)",
            -1, G_MAXINT, DEFAULT_NUM_BUFFERS,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
    g_object_class_install_property (gobject_class, PROP_DEVICE,
        g_param_spec_string ("device", "device",
            "Device location",
            DEFAULT_DEVICE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
    g_object_class_install_property (gobject_class, PROP_DEVICE_NAME,
        g_param_spec_string ("device-name", "Device name",
            "Name of the device", DEFAULT_DEVICE_NAME,
            G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
  
    /* Static controls */
    g_object_class_install_property (gobject_class, PROP_INITIAL_BITRATE,
        g_param_spec_uint ("initial-bitrate", "Initial bitrate",
            "Initial bitrate in bits/second (static control)",
            0, G_MAXUINT, DEFAULT_INITIAL_BITRATE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_SLICE_UNITS,
        g_param_spec_uint ("slice-units", "Slice units",
            "Slice units (static control)",
            0, G_MAXUINT16, DEFAULT_SLICE_UNITS,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_SLICE_MODE,
        g_param_spec_enum ("slice-mode", "Slice mode",
            "Defines the unit of the slice-units property (static control)",
            UVC_H264_SLICEMODE_TYPE,
            DEFAULT_SLICE_MODE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_IFRAME_PERIOD,
        g_param_spec_uint ("iframe-period", "I Frame Period",
            "Time between IDR frames in milliseconds (static control)",
            0, G_MAXUINT16, DEFAULT_IFRAME_PERIOD,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_USAGE_TYPE,
        g_param_spec_enum ("usage-type", "Usage type",
            "The usage type (static control)",
            UVC_H264_USAGETYPE_TYPE, DEFAULT_USAGE_TYPE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_ENTROPY,
        g_param_spec_enum ("entropy", "Entropy",
            "Entropy (static control)",
            UVC_H264_ENTROPY_TYPE, DEFAULT_ENTROPY,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_ENABLE_SEI,
        g_param_spec_boolean ("enable-sei", "Enable SEI",
            "Enable SEI picture timing (static control)",
            DEFAULT_ENABLE_SEI, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_NUM_REORDER_FRAMES,
        g_param_spec_uint ("num-reorder-frames", "Number of Reorder frames",
            "Number of B frames between the references frames (static control)",
            0, G_MAXUINT8, DEFAULT_NUM_REORDER_FRAMES,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_PREVIEW_FLIPPED,
        g_param_spec_boolean ("preview-flipped", "Flip preview",
            "Horizontal flipped image for non H.264 streams (static control)",
            DEFAULT_PREVIEW_FLIPPED, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
    g_object_class_install_property (gobject_class, PROP_LEAKY_BUCKET_SIZE,
        g_param_spec_uint ("leaky-bucket-size", "Size of the leaky bucket size",
            "Size of the leaky bucket size in milliseconds (static control)",
            0, G_MAXUINT16, DEFAULT_LEAKY_BUCKET_SIZE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_READY));
  
    /* Dynamic controls */
    g_object_class_install_property (gobject_class, PROP_RATE_CONTROL,
        g_param_spec_enum ("rate-control", "Rate control",
            "Rate control mode (static & dynamic control)",
            UVC_H264_RATECONTROL_TYPE, DEFAULT_RATE_CONTROL,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_FIXED_FRAMERATE,
        g_param_spec_boolean ("fixed-framerate", "Fixed framerate",
            "Fixed framerate (static & dynamic control)",
            DEFAULT_FIXED_FRAMERATE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MAX_MBPS,
        g_param_spec_uint ("max-mbps", "Max macroblocks/second",
            "The number of macroblocks per second for the maximum processing rate",
            0, G_MAXUINT, 0, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
    g_object_class_install_property (gobject_class, PROP_LEVEL_IDC,
        g_param_spec_uint ("level-idc", "Level IDC",
            "Level IDC (dynamic control)",
            0, G_MAXUINT8, DEFAULT_LEVEL_IDC,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_PEAK_BITRATE,
        g_param_spec_uint ("peak-bitrate", "Peak bitrate",
            "The peak bitrate in bits/second (dynamic control)",
            0, G_MAXUINT, DEFAULT_PEAK_BITRATE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_AVERAGE_BITRATE,
        g_param_spec_uint ("average-bitrate", "Average bitrate",
            "The average bitrate in bits/second (dynamic control)",
            0, G_MAXUINT, DEFAULT_AVERAGE_BITRATE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MIN_IFRAME_QP,
        g_param_spec_int ("min-iframe-qp", "Minimum I frame QP",
            "The minimum Quantization step size for I frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MIN_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MAX_IFRAME_QP,
        g_param_spec_int ("max-iframe-qp", "Minimum I frame QP",
            "The minimum Quantization step size for I frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MAX_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MIN_PFRAME_QP,
        g_param_spec_int ("min-pframe-qp", "Minimum P frame QP",
            "The minimum Quantization step size for P frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MIN_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MAX_PFRAME_QP,
        g_param_spec_int ("max-pframe-qp", "Minimum P frame QP",
            "The minimum Quantization step size for P frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MAX_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MIN_BFRAME_QP,
        g_param_spec_int ("min-bframe-qp", "Minimum B frame QP",
            "The minimum Quantization step size for B frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MIN_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_MAX_BFRAME_QP,
        g_param_spec_int ("max-bframe-qp", "Minimum B frame QP",
            "The minimum Quantization step size for B frames (dynamic control)",
            -G_MAXINT8, G_MAXINT8, DEFAULT_MAX_QP,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_LTR_BUFFER_SIZE,
        g_param_spec_int ("ltr-buffer-size", "LTR Buffer size",
            "Total number of Long-Term Reference frames (dynamic control)",
            0, G_MAXUINT8, DEFAULT_LTR_BUFFER_SIZE,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
    g_object_class_install_property (gobject_class, PROP_LTR_ENCODER_CONTROL,
        g_param_spec_int ("ltr-encoder-control", "LTR frames controled by device",
            "Number of LTR frames the device can control (dynamic control)",
            0, G_MAXUINT8, DEFAULT_LTR_ENCODER_CONTROL,
            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
            GST_PARAM_MUTABLE_PLAYING));
  
    _signals[SIGNAL_GET_ENUM_SETTING] =
        g_signal_new_class_handler ("get-enum-setting",
        G_TYPE_FROM_CLASS (klass),
        G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
        G_CALLBACK (gst_uvc_h264_src_get_enum_setting),
        NULL, NULL, NULL,
        G_TYPE_BOOLEAN, 3, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER, 0);
    _signals[SIGNAL_GET_BOOLEAN_SETTING] =
        g_signal_new_class_handler ("get-boolean-setting",
        G_TYPE_FROM_CLASS (klass),
        G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
        G_CALLBACK (gst_uvc_h264_src_get_boolean_setting), NULL, NULL, NULL,
        G_TYPE_BOOLEAN, 3, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER, 0);
    _signals[SIGNAL_GET_INT_SETTING] =
        g_signal_new_class_handler ("get-int-setting",
        G_TYPE_FROM_CLASS (klass),
        G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
        G_CALLBACK (gst_uvc_h264_src_get_int_setting), NULL, NULL, NULL,
        G_TYPE_BOOLEAN, 4, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER,
        G_TYPE_POINTER, 0);
  }
  
  static void
  gst_uvc_h264_src_init (GstUvcH264Src * self)
  {
    self->vfsrc =
        gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_VIEWFINDER_PAD_NAME,
        GST_PAD_SRC);
    gst_pad_set_query_function (self->vfsrc,
        GST_DEBUG_FUNCPTR (gst_uvc_h264_src_query));
    gst_element_add_pad (GST_ELEMENT (self), self->vfsrc);
  
    self->imgsrc =
        gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_IMAGE_PAD_NAME,
        GST_PAD_SRC);
    gst_element_add_pad (GST_ELEMENT (self), self->imgsrc);
  
    self->vidsrc =
        gst_ghost_pad_new_no_target (GST_BASE_CAMERA_SRC_VIDEO_PAD_NAME,
        GST_PAD_SRC);
    gst_pad_set_query_function (self->vidsrc,
        GST_DEBUG_FUNCPTR (gst_uvc_h264_src_query));
    gst_element_add_pad (GST_ELEMENT (self), self->vidsrc);
    gst_pad_add_probe (self->vidsrc, GST_PAD_PROBE_TYPE_BUFFER,
        gst_uvc_h264_src_buffer_probe, self, NULL);
    gst_pad_add_probe (self->vfsrc, GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
        gst_uvc_h264_src_event_probe, self, NULL);
    gst_pad_add_probe (self->vidsrc,
        GST_PAD_PROBE_TYPE_EVENT_UPSTREAM | GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM,
        gst_uvc_h264_src_event_probe, self, NULL);
  
    self->srcpad_event_func = GST_PAD_EVENTFUNC (self->vfsrc);
  
    gst_pad_set_event_function (self->imgsrc, gst_uvc_h264_src_event);
    gst_pad_set_event_function (self->vidsrc, gst_uvc_h264_src_event);
    gst_pad_set_event_function (self->vfsrc, gst_uvc_h264_src_event);
  
    g_signal_connect (self->vidsrc, "linked",
        (GCallback) gst_uvc_h264_src_pad_linking_cb, self);
    g_signal_connect (self->vidsrc, "unlinked",
        (GCallback) gst_uvc_h264_src_pad_linking_cb, self);
    g_signal_connect (self->vfsrc, "linked",
        (GCallback) gst_uvc_h264_src_pad_linking_cb, self);
    g_signal_connect (self->vfsrc, "unlinked",
        (GCallback) gst_uvc_h264_src_pad_linking_cb, self);
  
    self->v4l2_fd = -1;
    gst_base_camera_src_set_mode (GST_BASE_CAMERA_SRC (self), MODE_VIDEO);
  
    self->main_format = UVC_H264_SRC_FORMAT_NONE;
    self->main_width = 0;
    self->main_height = 0;
    self->main_frame_interval = 0;
    self->main_stream_format = UVC_H264_STREAMFORMAT_ANNEXB;
    self->main_profile = UVC_H264_PROFILE_CONSTRAINED_BASELINE;
    self->secondary_format = UVC_H264_SRC_FORMAT_NONE;
    self->secondary_width = 0;
    self->secondary_height = 0;
    self->secondary_frame_interval = 0;
  
    /* v4l2src properties */
    self->num_buffers = DEFAULT_NUM_BUFFERS;
    self->device = g_strdup (DEFAULT_DEVICE);
  
    /* Static controls */
    self->initial_bitrate = DEFAULT_INITIAL_BITRATE;
    self->slice_units = DEFAULT_SLICE_UNITS;
    self->slice_mode = DEFAULT_SLICE_MODE;
    self->iframe_period = DEFAULT_IFRAME_PERIOD;
    self->usage_type = DEFAULT_USAGE_TYPE;
    self->entropy = DEFAULT_ENTROPY;
    self->enable_sei = DEFAULT_ENABLE_SEI;
    self->num_reorder_frames = DEFAULT_NUM_REORDER_FRAMES;
    self->preview_flipped = DEFAULT_PREVIEW_FLIPPED;
    self->leaky_bucket_size = DEFAULT_LEAKY_BUCKET_SIZE;
  
    /* Dynamic controls */
    self->rate_control = DEFAULT_RATE_CONTROL;
    self->fixed_framerate = DEFAULT_FIXED_FRAMERATE;
    self->level_idc = DEFAULT_LEVEL_IDC;
    self->peak_bitrate = DEFAULT_PEAK_BITRATE;
    self->average_bitrate = DEFAULT_AVERAGE_BITRATE;
    self->min_qp[QP_I_FRAME] = DEFAULT_MIN_QP;
    self->max_qp[QP_I_FRAME] = DEFAULT_MAX_QP;
    self->min_qp[QP_P_FRAME] = DEFAULT_MIN_QP;
    self->max_qp[QP_P_FRAME] = DEFAULT_MAX_QP;
    self->min_qp[QP_B_FRAME] = DEFAULT_MIN_QP;
    self->max_qp[QP_B_FRAME] = DEFAULT_MAX_QP;
    self->ltr_buffer_size = DEFAULT_LTR_BUFFER_SIZE;
    self->ltr_encoder_control = DEFAULT_LTR_ENCODER_CONTROL;
  }
  
  static void
  gst_uvc_h264_src_dispose (GObject * object)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (object);
  
    if (self->usb_ctx)
      libusb_exit (self->usb_ctx);
    self->usb_ctx = NULL;
    g_free (self->jpeg_decoder_name);
    self->jpeg_decoder_name = NULL;
    g_free (self->colorspace_name);
    self->colorspace_name = NULL;
    g_free (self->device);
    self->device = NULL;
  
    G_OBJECT_CLASS (parent_class)->dispose (object);
  }
  
  static void
  gst_uvc_h264_src_set_property (GObject * object,
      guint prop_id, const GValue * value, GParamSpec * pspec)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (object);
  
    switch (prop_id) {
      case PROP_COLORSPACE_NAME:
        g_free (self->colorspace_name);
        self->colorspace_name = g_value_dup_string (value);
        break;
      case PROP_JPEG_DECODER_NAME:
        g_free (self->jpeg_decoder_name);
        self->jpeg_decoder_name = g_value_dup_string (value);
        break;
      case PROP_NUM_CLOCK_SAMPLES:
        self->num_clock_samples = g_value_get_int (value);
        if (self->mjpg_demux)
          g_object_set (self->mjpg_demux,
              "num-clock-samples", self->num_clock_samples, NULL);
        break;
        /* v4l2 properties */
      case PROP_NUM_BUFFERS:
        self->num_buffers = g_value_get_int (value);
        if (self->v4l2_src)
          g_object_set_property (G_OBJECT (self->v4l2_src), "num-buffers", value);
        break;
      case PROP_DEVICE:
        g_free (self->device);
        self->device = g_value_dup_string (value);
        if (self->v4l2_src)
          g_object_set_property (G_OBJECT (self->v4l2_src), "device", value);
        break;
        /* Static controls */
      case PROP_INITIAL_BITRATE:
        self->initial_bitrate = g_value_get_uint (value);
        break;
      case PROP_SLICE_UNITS:
        self->slice_units = g_value_get_uint (value);
        break;
      case PROP_SLICE_MODE:
        self->slice_mode = g_value_get_enum (value);
        break;
      case PROP_IFRAME_PERIOD:
        self->iframe_period = g_value_get_uint (value);
        break;
      case PROP_USAGE_TYPE:
        self->usage_type = g_value_get_enum (value);
        break;
      case PROP_ENTROPY:
        self->entropy = g_value_get_enum (value);
        break;
      case PROP_ENABLE_SEI:
        self->enable_sei = g_value_get_boolean (value);
        break;
      case PROP_NUM_REORDER_FRAMES:
        self->num_reorder_frames = g_value_get_uint (value);
        break;
      case PROP_PREVIEW_FLIPPED:
        self->preview_flipped = g_value_get_boolean (value);
        break;
      case PROP_LEAKY_BUCKET_SIZE:
        self->leaky_bucket_size = g_value_get_uint (value);
        break;
  
  
        /* Dynamic controls */
      case PROP_RATE_CONTROL:
        self->rate_control = g_value_get_enum (value);
        set_rate_control (self);
        update_rate_control (self);
        break;
      case PROP_FIXED_FRAMERATE:
        self->fixed_framerate = g_value_get_boolean (value);
        set_rate_control (self);
        update_rate_control (self);
        break;
      case PROP_LEVEL_IDC:
        self->level_idc = g_value_get_uint (value);
        set_level_idc (self);
        update_level_idc_and_get_max_mbps (self);
        break;
      case PROP_PEAK_BITRATE:
        self->peak_bitrate = g_value_get_uint (value);
        set_bitrate (self);
        update_bitrate (self);
        break;
      case PROP_AVERAGE_BITRATE:
        self->average_bitrate = g_value_get_uint (value);
        set_bitrate (self);
        update_bitrate (self);
        break;
      case PROP_MIN_IFRAME_QP:
        self->min_qp[QP_I_FRAME] = g_value_get_int (value);
        set_qp (self, QP_I_FRAME);
        update_qp (self, QP_I_FRAME);
        break;
      case PROP_MAX_IFRAME_QP:
        self->max_qp[QP_I_FRAME] = g_value_get_int (value);
        set_qp (self, QP_I_FRAME);
        update_qp (self, QP_I_FRAME);
        break;
      case PROP_MIN_PFRAME_QP:
        self->min_qp[QP_P_FRAME] = g_value_get_int (value);
        set_qp (self, QP_P_FRAME);
        update_qp (self, QP_P_FRAME);
        break;
      case PROP_MAX_PFRAME_QP:
        self->max_qp[QP_P_FRAME] = g_value_get_int (value);
        set_qp (self, QP_P_FRAME);
        update_qp (self, QP_P_FRAME);
        break;
      case PROP_MIN_BFRAME_QP:
        self->min_qp[QP_B_FRAME] = g_value_get_int (value);
        set_qp (self, QP_B_FRAME);
        update_qp (self, QP_B_FRAME);
        break;
      case PROP_MAX_BFRAME_QP:
        self->max_qp[QP_B_FRAME] = g_value_get_int (value);
        set_qp (self, QP_B_FRAME);
        update_qp (self, QP_B_FRAME);
        break;
      case PROP_LTR_BUFFER_SIZE:
        self->ltr_buffer_size = g_value_get_int (value);
        set_ltr (self);
        update_ltr (self);
        break;
      case PROP_LTR_ENCODER_CONTROL:
        self->ltr_encoder_control = g_value_get_int (value);
        set_ltr (self);
        update_ltr (self);
        break;
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
        break;
    }
  }
  
  static void
  gst_uvc_h264_src_get_property (GObject * object,
      guint prop_id, GValue * value, GParamSpec * pspec)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (object);
    uvcx_video_config_probe_commit_t probe;
  
    switch (prop_id) {
      case PROP_INITIAL_BITRATE:
      case PROP_SLICE_UNITS:
      case PROP_SLICE_MODE:
      case PROP_IFRAME_PERIOD:
      case PROP_USAGE_TYPE:
      case PROP_ENTROPY:
      case PROP_ENABLE_SEI:
      case PROP_NUM_REORDER_FRAMES:
      case PROP_PREVIEW_FLIPPED:
      case PROP_LEAKY_BUCKET_SIZE:
        fill_probe_commit (self, &probe, 0, 0, 0, 0, 0);
        if (GST_STATE (self) >= GST_STATE_PAUSED) {
          if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR,
                  (guchar *) & probe))
            GST_WARNING_OBJECT (self, "probe_setting GET_CUR error");
        }
        break;
      default:
        break;
    }
  
    switch (prop_id) {
      case PROP_COLORSPACE_NAME:
        g_value_set_string (value, self->colorspace_name);
        break;
      case PROP_JPEG_DECODER_NAME:
        g_value_set_string (value, self->jpeg_decoder_name);
        break;
      case PROP_NUM_CLOCK_SAMPLES:
        g_value_set_int (value, self->num_clock_samples);
        break;
        /* v4l2src properties */
      case PROP_NUM_BUFFERS:
        g_value_set_int (value, self->num_buffers);
        break;
      case PROP_DEVICE:
        g_value_set_string (value, self->device);
        break;
      case PROP_DEVICE_NAME:
        if (self->v4l2_src)
          g_object_get_property (G_OBJECT (self->v4l2_src), "device-name", value);
        else
          g_value_set_static_string (value, "");
        break;
        /* Static controls */
      case PROP_INITIAL_BITRATE:
        g_value_set_uint (value, probe.dwBitRate);
        break;
      case PROP_SLICE_UNITS:
        g_value_set_uint (value, probe.wSliceUnits);
        break;
      case PROP_SLICE_MODE:
        g_value_set_enum (value, probe.wSliceMode);
        break;
      case PROP_IFRAME_PERIOD:
        g_value_set_uint (value, probe.wIFramePeriod);
        break;
      case PROP_USAGE_TYPE:
        g_value_set_enum (value, probe.bUsageType);
        break;
      case PROP_ENTROPY:
        g_value_set_enum (value, probe.bEntropyCABAC);
        break;
      case PROP_ENABLE_SEI:
        g_value_set_boolean (value,
            (probe.bTimestamp == UVC_H264_TIMESTAMP_SEI_ENABLE));
        break;
      case PROP_NUM_REORDER_FRAMES:
        g_value_set_uint (value, probe.bNumOfReorderFrames);
        break;
      case PROP_PREVIEW_FLIPPED:
        g_value_set_boolean (value,
            (probe.bPreviewFlipped == UVC_H264_PREFLIPPED_HORIZONTAL));
        break;
      case PROP_LEAKY_BUCKET_SIZE:
        g_value_set_uint (value, probe.wLeakyBucketSize);
        break;
  
        /* Dynamic controls */
      case PROP_RATE_CONTROL:
        update_rate_control (self);
        g_value_set_enum (value, self->rate_control);
        break;
      case PROP_FIXED_FRAMERATE:
        update_rate_control (self);
        g_value_set_boolean (value, self->fixed_framerate);
        break;
      case PROP_MAX_MBPS:
        g_value_set_uint (value, update_level_idc_and_get_max_mbps (self));
        break;
      case PROP_LEVEL_IDC:
        update_level_idc_and_get_max_mbps (self);
        g_value_set_uint (value, self->level_idc);
        break;
      case PROP_PEAK_BITRATE:
        update_bitrate (self);
        g_value_set_uint (value, self->peak_bitrate);
        break;
      case PROP_AVERAGE_BITRATE:
        update_bitrate (self);
        g_value_set_uint (value, self->average_bitrate);
        break;
      case PROP_MIN_IFRAME_QP:
        update_qp (self, QP_I_FRAME);
        g_value_set_int (value, self->min_qp[QP_I_FRAME]);
        break;
      case PROP_MAX_IFRAME_QP:
        update_qp (self, QP_I_FRAME);
        g_value_set_int (value, self->max_qp[QP_I_FRAME]);
        break;
      case PROP_MIN_PFRAME_QP:
        update_qp (self, QP_P_FRAME);
        g_value_set_int (value, self->min_qp[QP_P_FRAME]);
        break;
      case PROP_MAX_PFRAME_QP:
        update_qp (self, QP_P_FRAME);
        g_value_set_int (value, self->max_qp[QP_P_FRAME]);
        break;
      case PROP_MIN_BFRAME_QP:
        update_qp (self, QP_B_FRAME);
        g_value_set_int (value, self->min_qp[QP_B_FRAME]);
        break;
      case PROP_MAX_BFRAME_QP:
        update_qp (self, QP_B_FRAME);
        g_value_set_int (value, self->max_qp[QP_B_FRAME]);
        break;
      case PROP_LTR_BUFFER_SIZE:
        update_ltr (self);
        g_value_set_int (value, self->ltr_buffer_size);
        break;
      case PROP_LTR_ENCODER_CONTROL:
        update_ltr (self);
        g_value_set_int (value, self->ltr_encoder_control);
        break;
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
        break;
    }
  }
  
  /* Set dynamic controls */
  static void
  set_rate_control (GstUvcH264Src * self)
  {
    uvcx_rate_control_mode_t req;
  
    if (!xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " RATE_CONTROL GET_CUR error");
      return;
    }
  
    req.bRateControlMode = self->rate_control;
    if (self->fixed_framerate)
      req.bRateControlMode |= UVC_H264_RATECONTROL_FIXED_FRM_FLG;
  
    if (!xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_SET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " RATE_CONTROL SET_CUR error");
      return;
    }
  }
  
  static void
  set_level_idc (GstUvcH264Src * self)
  {
    uvcx_video_advance_config_t req;
  
    if (!xu_query (self, UVCX_VIDEO_ADVANCE_CONFIG, UVC_GET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " VIDEO_ADVANCE_CONFIG GET_CUR error");
      return;
    }
  
    req.blevel_idc = self->level_idc;
    if (!xu_query (self, UVCX_VIDEO_ADVANCE_CONFIG, UVC_SET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " VIDEO_ADVANCE_CONFIG SET_CUR error");
      return;
    }
  }
  
  static void
  set_bitrate (GstUvcH264Src * self)
  {
    uvcx_bitrate_layers_t req;
  
    if (!xu_query (self, UVCX_BITRATE_LAYERS, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " BITRATE_LAYERS GET_CUR error");
      return;
    }
  
    req.dwPeakBitrate = self->peak_bitrate;
    req.dwAverageBitrate = self->average_bitrate;
    if (!xu_query (self, UVCX_BITRATE_LAYERS, UVC_SET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " BITRATE_LAYERS SET_CUR error");
      return;
    }
  }
  
  static void
  set_qp (GstUvcH264Src * self, gint type)
  {
    uvcx_qp_steps_layers_t req;
  
    req.wLayerID = 0;
    switch (type) {
      case QP_I_FRAME:
        req.bFrameType = UVC_H264_QP_STEPS_I_FRAME_TYPE;
        break;
      case QP_P_FRAME:
        req.bFrameType = UVC_H264_QP_STEPS_P_FRAME_TYPE;
        break;
      case QP_B_FRAME:
        req.bFrameType = UVC_H264_QP_STEPS_B_FRAME_TYPE;
        break;
      default:
        return;
    }
    req.bMinQp = 0;
    req.bMaxQp = 0;
    if (!xu_query (self, UVCX_QP_STEPS_LAYERS, UVC_SET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " QP_STEPS_LAYERS SET_CUR error");
      return;
    }
  
    if (!xu_query (self, UVCX_QP_STEPS_LAYERS, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " QP_STEPS_LAYERS GET_CUR error");
      return;
    }
  
    req.bMinQp = self->min_qp[type];
    req.bMaxQp = self->max_qp[type];
    if (!xu_query (self, UVCX_QP_STEPS_LAYERS, UVC_SET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " QP_STEPS_LAYERS SET_CUR error");
      return;
    }
  }
  
  static void
  set_ltr (GstUvcH264Src * self)
  {
    uvcx_ltr_buffer_size_control_t req;
  
    if (!xu_query (self, UVCX_LTR_BUFFER_SIZE_CONTROL, UVC_GET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " LTR_BUFFER_SIZE GET_CUR error");
      return;
    }
  
    req.bLTRBufferSize = self->ltr_buffer_size;
    req.bLTREncoderControl = self->ltr_encoder_control;
    if (!xu_query (self, UVCX_LTR_BUFFER_SIZE_CONTROL, UVC_SET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, "LTR_BUFFER_SIZE  SET_CUR error");
      return;
    }
  }
  
  /* Get Dynamic controls */
  
  static void
  update_rate_control (GstUvcH264Src * self)
  {
    uvcx_rate_control_mode_t req;
  
    if (!xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " RATE_CONTROL GET_CUR error");
      return;
    }
  
    if (self->rate_control != (req.bRateControlMode &
            ~UVC_H264_RATECONTROL_FIXED_FRM_FLG)) {
      self->rate_control = (req.bRateControlMode &
          ~UVC_H264_RATECONTROL_FIXED_FRM_FLG);
      g_object_notify (G_OBJECT (self), "rate-control");
    }
    if (self->fixed_framerate != ((req.bRateControlMode &
                UVC_H264_RATECONTROL_FIXED_FRM_FLG) != 0)) {
      self->fixed_framerate = ((req.bRateControlMode &
              UVC_H264_RATECONTROL_FIXED_FRM_FLG) != 0);
      g_object_notify (G_OBJECT (self), "fixed-framerate");
    }
  }
  
  
  static guint32
  update_level_idc_and_get_max_mbps (GstUvcH264Src * self)
  {
    uvcx_video_advance_config_t req;
  
    if (!xu_query (self, UVCX_VIDEO_ADVANCE_CONFIG, UVC_GET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " VIDEO_ADVANCE_CONFIG GET_CUR error");
      return 0;
    }
  
    if (self->level_idc != req.blevel_idc) {
      self->level_idc = req.blevel_idc;
      g_object_notify (G_OBJECT (self), "level-idc");
    }
    return req.dwMb_max;
  }
  
  static void
  update_bitrate (GstUvcH264Src * self)
  {
    uvcx_bitrate_layers_t req;
  
    if (!xu_query (self, UVCX_BITRATE_LAYERS, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " BITRATE_LAYERS GET_CUR error");
      return;
    }
    if (self->peak_bitrate != req.dwPeakBitrate) {
      self->peak_bitrate = req.dwPeakBitrate;
      g_object_notify (G_OBJECT (self), "peak-bitrate");
    }
    if (self->average_bitrate != req.dwAverageBitrate) {
      self->average_bitrate = req.dwAverageBitrate;
      g_object_notify (G_OBJECT (self), "average-bitrate");
    }
  }
  
  static gboolean
  update_qp (GstUvcH264Src * self, gint type)
  {
    uvcx_qp_steps_layers_t req;
    guint8 frame_type;
  
    req.wLayerID = 0;
    switch (type) {
      case QP_I_FRAME:
        frame_type = UVC_H264_QP_STEPS_I_FRAME_TYPE;
        break;
      case QP_P_FRAME:
        frame_type = UVC_H264_QP_STEPS_P_FRAME_TYPE;
        break;
      case QP_B_FRAME:
        frame_type = UVC_H264_QP_STEPS_B_FRAME_TYPE;
        break;
      default:
        return FALSE;
    }
    req.bFrameType = frame_type;
    req.bMinQp = 0;
    req.bMaxQp = 0;
    if (!xu_query (self, UVCX_QP_STEPS_LAYERS, UVC_SET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " QP_STEPS_LAYERS SET_CUR error");
      return FALSE;
    }
  
    if (!xu_query (self, UVCX_QP_STEPS_LAYERS, UVC_GET_CUR, (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " QP_STEPS_LAYERS GET_CUR error");
      return FALSE;
    }
  
    if (req.bFrameType == frame_type) {
      if (self->min_qp[type] != req.bMinQp) {
        self->min_qp[type] = req.bMinQp;
        switch (type) {
          case QP_I_FRAME:
            g_object_notify (G_OBJECT (self), "min-iframe-qp");
            break;
          case QP_P_FRAME:
            g_object_notify (G_OBJECT (self), "min-pframe-qp");
            break;
          case QP_B_FRAME:
            g_object_notify (G_OBJECT (self), "min-bframe-qp");
            break;
          default:
            break;
        }
      }
      if (self->max_qp[type] != req.bMaxQp) {
        self->max_qp[type] = req.bMaxQp;
        switch (type) {
          case QP_I_FRAME:
            g_object_notify (G_OBJECT (self), "max-iframe-qp");
            break;
          case QP_P_FRAME:
            g_object_notify (G_OBJECT (self), "max-pframe-qp");
            break;
          case QP_B_FRAME:
            g_object_notify (G_OBJECT (self), "max-bframe-qp");
            break;
          default:
            break;
        }
      }
      return TRUE;
    } else {
      self->min_qp[type] = 0xFF;
      self->max_qp[type] = 0xFF;
      return FALSE;
    }
  }
  
  static void
  update_ltr (GstUvcH264Src * self)
  {
    uvcx_ltr_buffer_size_control_t req;
  
    if (!xu_query (self, UVCX_LTR_BUFFER_SIZE_CONTROL, UVC_GET_CUR,
            (guchar *) & req)) {
      GST_WARNING_OBJECT (self, " LTR_BUFFER_SIZE GET_CUR error");
      return;
    }
  
    if (self->ltr_buffer_size != req.bLTRBufferSize) {
      self->ltr_buffer_size = req.bLTRBufferSize;
      g_object_notify (G_OBJECT (self), "ltr-buffer-size");
    }
    if (self->ltr_encoder_control != req.bLTREncoderControl) {
      self->ltr_encoder_control = req.bLTREncoderControl;
      g_object_notify (G_OBJECT (self), "ltr-encoder-control");
    }
  }
  
  #define STORE_MIN_DEF_MAX(type)                         \
    *(type *)min = *((type *) (min_p + offset));          \
    *(type *)def = *((type *) (def_p + offset));          \
    *(type *)max = *((type *) (max_p + offset));
  
  static gboolean
  probe_setting (GstUvcH264Src * self, uvcx_control_selector_t selector,
      guint offset, gint size, gpointer min, gpointer def, gpointer max)
  {
    guchar *min_p, *def_p, *max_p;
    gboolean ret = FALSE;
    __u16 len;
  
    if (!xu_query (self, selector, UVC_GET_LEN, (guchar *) & len)) {
      GST_WARNING_OBJECT (self, "probe_setting GET_LEN error");
      return FALSE;
    }
    min_p = g_malloc0 (len);
    def_p = g_malloc0 (len);
    max_p = g_malloc0 (len);
  
    if (!xu_query (self, selector, UVC_GET_MIN, min_p)) {
      GST_WARNING_OBJECT (self, "probe_setting GET_MIN error");
      goto end;
    }
    if (!xu_query (self, selector, UVC_GET_DEF, def_p)) {
      GST_WARNING_OBJECT (self, "probe_setting GET_DEF error");
      goto end;
    }
    if (!xu_query (self, selector, UVC_GET_MAX, max_p)) {
      GST_WARNING_OBJECT (self, "probe_setting GET_MAX error");
      goto end;
    }
  
    switch (size) {
      case -1:
        STORE_MIN_DEF_MAX (gint8);
        ret = TRUE;
        break;
      case 1:
        STORE_MIN_DEF_MAX (guint8);
        ret = TRUE;
        break;
      case -2:
        STORE_MIN_DEF_MAX (gint16);
        ret = TRUE;
        break;
      case 2:
        STORE_MIN_DEF_MAX (guint16);
        ret = TRUE;
        break;
      case -4:
        STORE_MIN_DEF_MAX (gint32);
        ret = TRUE;
        break;
      case 4:
        STORE_MIN_DEF_MAX (guint32);
        ret = TRUE;
        break;
      default:
        break;
    }
  
  end:
    g_free (min_p);
    g_free (def_p);
    g_free (max_p);
  
    return ret;
  }
  
  static gboolean
  test_enum_setting (GstUvcH264Src * self, guint offset, guint size,
      guint16 value)
  {
    uvcx_video_config_probe_commit_t cur;
    uvcx_video_config_probe_commit_t req;
    guchar *req_p = (guchar *) & req;
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR, (guchar *) & cur)) {
      GST_WARNING_OBJECT (self, " GET_CUR error");
      return FALSE;
    }
  
    req = cur;
  
    if (size == 1)
      *((guint8 *) (req_p + offset)) = (guint8) value;
    else
      *((guint16 *) (req_p + offset)) = value;
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR, req_p)) {
      GST_WARNING_OBJECT (self, " SET_CUR error");
      return FALSE;
    }
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR, req_p)) {
      GST_WARNING_OBJECT (self, " GET_CUR error");
      return FALSE;
    }
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR, (guchar *) & cur)) {
      GST_WARNING_OBJECT (self, " SET_CUR error");
      return FALSE;
    }
  
    if (size == 1)
      return *((guint8 *) (req_p + offset)) == (guint8) value;
    else
      return *((guint16 *) (req_p + offset)) == value;
  }
  
  static gboolean
  gst_uvc_h264_src_get_enum_setting (GstUvcH264Src * self, gchar * property,
      gint * mask, gint * default_value)
  {
    guint8 min, def, max;
    guint8 en;
    gboolean ret = FALSE;
  
    if (g_strcmp0 (property, "slice-mode") == 0) {
      guint16 min16, def16, max16;
      guint16 en16;
  
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, wSliceMode), 2,
          &min16, &def16, &max16);
      if (ret) {
        *default_value = def16;
        *mask = 0;
        for (en16 = min16; en16 <= max16; en16++) {
          if (test_enum_setting (self, offsetof (uvcx_video_config_probe_commit_t,
                      wSliceMode), 2, en16))
            *mask |= (1 << en16);
        }
      }
    } else if (g_strcmp0 (property, "usage-type") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, bUsageType), 1,
          &min, &def, &max);
      if (ret) {
        *default_value = def;
        *mask = 0;
        for (en = min; en <= max; en++) {
          if (test_enum_setting (self, offsetof (uvcx_video_config_probe_commit_t,
                      bUsageType), 1, en))
            *mask |= (1 << en);
        }
      }
    } else if (g_strcmp0 (property, "entropy") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, bEntropyCABAC), 1,
          &min, &def, &max);
      if (ret) {
        *mask = (1 << min) | (1 << max);
        *default_value = def;
      }
    } else if (g_strcmp0 (property, "rate-control") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, bRateControlMode), 1,
          &min, &def, &max);
      if (ret) {
        uvcx_rate_control_mode_t cur;
  
        *default_value = def;
        *mask = 0;
  
        if (!xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_GET_CUR,
                (guchar *) & cur)) {
          GST_WARNING_OBJECT (self, " CONTROL_MODE GET_CUR error");
          return FALSE;
        }
  
        for (en = min; en <= max; en++) {
          uvcx_rate_control_mode_t req = { 0, en };
  
          if (xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_SET_CUR,
                  (guchar *) & req) &&
              xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_GET_CUR,
                  (guchar *) & req) && req.bRateControlMode == en)
            *mask |= (1 << en);
        }
        if (!xu_query (self, UVCX_RATE_CONTROL_MODE, UVC_SET_CUR,
                (guchar *) & cur)) {
          GST_WARNING_OBJECT (self, " CONTROL_MODE SET_CUR error");
          return FALSE;
        }
      }
    }
  
    return ret;
  }
  
  static gboolean
  gst_uvc_h264_src_get_boolean_setting (GstUvcH264Src * self, gchar * property,
      gboolean * changeable, gboolean * default_value)
  {
    guint8 min, def, max;
    gboolean ret = FALSE;
  
    if (g_strcmp0 (property, "enable-sei") == 0) {
      if ((ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
                  offsetof (uvcx_video_config_probe_commit_t, bTimestamp), 1,
                  &min, &def, &max))) {
        *changeable = (min != max);
        *default_value = (def != 0);
      }
    } else if (g_strcmp0 (property, "preview-flipped") == 0) {
      if ((ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
                  offsetof (uvcx_video_config_probe_commit_t, bPreviewFlipped), 1,
                  &min, &def, &max))) {
        *changeable = (min != max);
        *default_value = (def != 0);
      }
    } else if (g_strcmp0 (property, "fixed-framerate") == 0) {
      if ((ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
                  offsetof (uvcx_video_config_probe_commit_t, bRateControlMode),
                  1, &min, &def, &max))) {
        *changeable = ((max & UVC_H264_RATECONTROL_FIXED_FRM_FLG) != 0);
        *default_value = ((def & UVC_H264_RATECONTROL_FIXED_FRM_FLG) != 0);
      }
    }
  
    return ret;
  }
  
  static gboolean
  gst_uvc_h264_src_get_int_setting (GstUvcH264Src * self, gchar * property,
      gint * min, gint * def, gint * max)
  {
    guint32 min32, def32, max32;
    guint16 min16, def16, max16;
    guint8 min8, def8, max8;
    gint8 smin8, sdef8, smax8;
    gboolean ret = FALSE;
  
    GST_DEBUG_OBJECT (self, "Probing int property %s", property);
    if (g_strcmp0 (property, "initial-bitrate") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, dwBitRate), 4,
          &min32, &def32, &max32);
      if (ret) {
        *min = min32;
        *def = def32;
        *max = max32;
      }
    } else if (g_strcmp0 (property, "slice-units") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, wSliceUnits), 2,
          &min16, &def16, &max16);
      if (ret) {
        *min = min16;
        *def = def16;
        *max = max16;
      }
    } else if (g_strcmp0 (property, "iframe-period") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, wIFramePeriod), 2,
          &min16, &def16, &max16);
      if (ret) {
        *min = min16;
        *def = def16;
        *max = max16;
      }
    } else if (g_strcmp0 (property, "num-reorder-frames") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, bNumOfReorderFrames), 1,
          &min8, &def8, &max8);
      if (ret) {
        *min = min8;
        *def = def8;
        *max = max8;
      }
    } else if (g_strcmp0 (property, "leaky-bucket-size") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_CONFIG_PROBE,
          offsetof (uvcx_video_config_probe_commit_t, wLeakyBucketSize), 2,
          &min16, &def16, &max16);
      if (ret) {
        *min = min16;
        *def = def16;
        *max = max16;
      }
    } else if (g_strcmp0 (property, "level-idc") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_ADVANCE_CONFIG,
          offsetof (uvcx_video_advance_config_t, blevel_idc), 1,
          &min8, &def8, &max8);
      if (ret) {
        *min = min8;
        *def = def8;
        *max = max8;
      }
    } else if (g_strcmp0 (property, "max-mbps") == 0) {
      ret = probe_setting (self, UVCX_VIDEO_ADVANCE_CONFIG,
          offsetof (uvcx_video_advance_config_t, dwMb_max), 4,
          &min32, &def32, &max32);
      if (ret) {
        *min = min32;
        *def = def32;
        *max = max32;
      }
    } else if (g_strcmp0 (property, "peak-bitrate") == 0) {
      ret = probe_setting (self, UVCX_BITRATE_LAYERS,
          offsetof (uvcx_bitrate_layers_t, dwPeakBitrate), 4,
          &min32, &def32, &max32);
      if (ret) {
        *min = min32;
        *def = def32;
        *max = max32;
      }
    } else if (g_strcmp0 (property, "average-bitrate") == 0) {
      ret = probe_setting (self, UVCX_BITRATE_LAYERS,
          offsetof (uvcx_bitrate_layers_t, dwAverageBitrate), 4,
          &min32, &def32, &max32);
      if (ret) {
        *min = min32;
        *def = def32;
        *max = max32;
      }
    } else if (g_strcmp0 (property, "min-iframe-qp") == 0) {
      if (update_qp (self, QP_I_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMinQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "max-iframe-qp") == 0) {
      if (update_qp (self, QP_I_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMaxQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "min-pframe-qp") == 0) {
      if (update_qp (self, QP_P_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMinQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "max-pframe-qp") == 0) {
      if (update_qp (self, QP_P_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMaxQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "min-bframe-qp") == 0) {
      if (update_qp (self, QP_B_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMinQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "max-bframe-qp") == 0) {
      if (update_qp (self, QP_B_FRAME))
        ret = probe_setting (self, UVCX_QP_STEPS_LAYERS,
            offsetof (uvcx_qp_steps_layers_t, bMaxQp), 1, &smin8, &sdef8, &smax8);
      if (ret) {
        *min = smin8;
        *def = sdef8;
        *max = smax8;
      }
    } else if (g_strcmp0 (property, "ltr-buffer-size") == 0) {
      ret = probe_setting (self, UVCX_LTR_BUFFER_SIZE_CONTROL,
          offsetof (uvcx_ltr_buffer_size_control_t, bLTRBufferSize), 1,
          &min8, &def8, &max8);
      if (ret) {
        *min = min8;
        *def = def8;
        *max = max8;
      }
    } else if (g_strcmp0 (property, "ltr-encoder-control") == 0) {
      ret = probe_setting (self, UVCX_LTR_BUFFER_SIZE_CONTROL,
          offsetof (uvcx_ltr_buffer_size_control_t, bLTREncoderControl), 1,
          &min8, &def8, &max8);
      if (ret) {
        *min = min8;
        *def = def8;
        *max = max8;
      }
    } else {
      g_return_val_if_reached (FALSE);
    }
  
    return ret;
  }
  
  static GstPadProbeReturn
  gst_uvc_h264_src_event_probe (GstPad * pad, GstPadProbeInfo * info,
      gpointer user_data)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (user_data);
    GstPadProbeReturn ret = GST_PAD_PROBE_OK;
    GstEvent *event = info->data;
  
    switch (GST_EVENT_TYPE (event)) {
      case GST_EVENT_SEGMENT:
        if (pad == self->vidsrc) {
          const GstSegment *s;
  
          gst_event_parse_segment (event, &s);
          gst_segment_copy_into (s, &self->segment);
        }
        break;
      case GST_EVENT_EOS:
        ret = self->reconfiguring ? GST_PAD_PROBE_DROP : GST_PAD_PROBE_OK;
        break;
      default:
        break;
    }
  
    return ret;
  }
  
  static GstPadProbeReturn
  gst_uvc_h264_src_buffer_probe (GstPad * pad, GstPadProbeInfo * info,
      gpointer user_data)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (user_data);
    GstBuffer *buffer = info->data;
  
    /* TODO: Check the NALU type and make sure it is a keyframe */
    if (self->key_unit_event) {
      GstClockTime ts, running_time, stream_time;
      gboolean all_headers;
      guint count;
      GstEvent *downstream;
  
      if (gst_video_event_parse_upstream_force_key_unit (self->key_unit_event,
              &ts, &all_headers, &count)) {
        if (!GST_CLOCK_TIME_IS_VALID (ts)) {
          ts = GST_BUFFER_TIMESTAMP (buffer);
        }
        running_time = gst_segment_to_running_time (&self->segment,
            GST_FORMAT_TIME, ts);
  
        stream_time = gst_segment_to_stream_time (&self->segment,
            GST_FORMAT_TIME, ts);
  
        GST_DEBUG_OBJECT (self, "Sending downstream force-key-unit : %d - %d ts=%"
            GST_TIME_FORMAT " running time =%" GST_TIME_FORMAT " stream=%"
            GST_TIME_FORMAT, all_headers, count, GST_TIME_ARGS (ts),
            GST_TIME_ARGS (running_time), GST_TIME_ARGS (stream_time));
        downstream = gst_video_event_new_downstream_force_key_unit (ts,
            stream_time, running_time, all_headers, count);
        gst_pad_push_event (self->vidsrc, downstream);
        gst_event_replace (&self->key_unit_event, NULL);
      }
    }
    return TRUE;
  }
  
  static gboolean
  gst_uvc_h264_src_parse_event (GstUvcH264Src * self, GstPad * pad,
      GstEvent * event)
  {
    const GstStructure *s = gst_event_get_structure (event);
  
    switch (GST_EVENT_TYPE (event)) {
      case GST_EVENT_CUSTOM_UPSTREAM:
        if (pad == self->vidsrc && self->main_format == UVC_H264_SRC_FORMAT_H264) {
          if (gst_video_event_is_force_key_unit (event)) {
            uvcx_picture_type_control_t req = { 0, 0 };
            GstClockTime ts;
            gboolean all_headers;
  
            if (gst_video_event_parse_upstream_force_key_unit (event,
                    &ts, &all_headers, NULL)) {
              GST_INFO_OBJECT (self, "Received upstream force-key-unit : %d %"
                  GST_TIME_FORMAT, all_headers, GST_TIME_ARGS (ts));
              /* TODO: wait until 'ts' time is reached */
              if (all_headers)
                req.wPicType = UVC_H264_PICTYPE_IDR_WITH_PPS_SPS;
              else
                req.wPicType = UVC_H264_PICTYPE_IDR;
  
              if (!xu_query (self, UVCX_PICTURE_TYPE_CONTROL, UVC_SET_CUR,
                      (guchar *) & req)) {
                GST_WARNING_OBJECT (self, " PICTURE_TYPE_CONTROL SET_CUR error");
              } else {
                gst_event_replace (&self->key_unit_event, event);
                gst_event_unref (event);
  
                return TRUE;
              }
            }
          } else if (s &&
              gst_structure_has_name (s, "uvc-h264-ltr-picture-control")) {
            guint put_at, encode_using;
  
            if (gst_structure_get_uint (s, "put-at", &put_at) &&
                gst_structure_get_uint (s, "encode-using", &encode_using)) {
              uvcx_ltr_picture_control req = { 0, put_at, encode_using };
  
              if (!xu_query (self, UVCX_LTR_PICTURE_CONTROL, UVC_SET_CUR,
                      (guchar *) & req)) {
                GST_WARNING_OBJECT (self, " LTR PICTURE_CONTROL SET_CUR error");
              } else {
                gst_event_unref (event);
  
                return TRUE;
              }
            }
            return TRUE;
          } else if (s && gst_structure_has_name (s, "uvc-h264-bitrate-control")) {
            guint average, peak;
  
            if (gst_structure_get_uint (s, "average-bitrate", &average) &&
                gst_structure_get_uint (s, "peak-bitrate", &peak)) {
              self->average_bitrate = average;
              self->peak_bitrate = peak;
              set_bitrate (self);
              update_bitrate (self);
  
              gst_event_unref (event);
  
              return TRUE;
            }
          } else if (s && gst_structure_has_name (s, "uvc-h264-qp-control")) {
            gint min_qp, max_qp;
            gboolean valid_event = FALSE;
  
            if (gst_structure_get_int (s, "min-iframe-qp", &min_qp) &&
                gst_structure_get_int (s, "max-iframe-qp", &max_qp)) {
              self->min_qp[QP_I_FRAME] = min_qp;
              self->max_qp[QP_I_FRAME] = max_qp;
              set_qp (self, QP_I_FRAME);
              update_qp (self, QP_I_FRAME);
              valid_event = TRUE;
            }
            if (gst_structure_get_int (s, "min-pframe-qp", &min_qp) &&
                gst_structure_get_int (s, "max-pframe-qp", &max_qp)) {
              self->min_qp[QP_P_FRAME] = min_qp;
              self->max_qp[QP_P_FRAME] = max_qp;
              set_qp (self, QP_P_FRAME);
              update_qp (self, QP_P_FRAME);
              valid_event = TRUE;
            }
            if (gst_structure_get_int (s, "min-bframe-qp", &min_qp) &&
                gst_structure_get_int (s, "max-bframe-qp", &max_qp)) {
              self->min_qp[QP_B_FRAME] = min_qp;
              self->max_qp[QP_B_FRAME] = max_qp;
              set_qp (self, QP_B_FRAME);
              update_qp (self, QP_B_FRAME);
              valid_event = TRUE;
            }
  
            if (valid_event) {
              gst_event_unref (event);
  
              return TRUE;
            }
          } else if (s && gst_structure_has_name (s, "uvc-h264-rate-control")) {
            UvcH264RateControl rate;
            gboolean fixed_framerate;
  
            if (gst_structure_get_enum (s, "rate-control",
                    UVC_H264_RATECONTROL_TYPE, (gint *) & rate) &&
                gst_structure_get_boolean (s, "fixed-framerate",
                    &fixed_framerate)) {
              self->rate_control = rate;
              self->fixed_framerate = fixed_framerate;
              set_rate_control (self);
              update_rate_control (self);
  
              gst_event_unref (event);
  
              return TRUE;
            }
          } else if (s && gst_structure_has_name (s, "uvc-h264-level-idc")) {
            guint level_idc;
  
            if (gst_structure_get_uint (s, "level-idc", &level_idc)) {
              self->level_idc = level_idc;
              set_level_idc (self);
              update_level_idc_and_get_max_mbps (self);
  
              gst_event_unref (event);
            }
          }
        }
        break;
      default:
        break;
    }
  
    return FALSE;
  }
  
  static gboolean
  gst_uvc_h264_src_send_event (GstElement * element, GstEvent * event)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (element);
  
    if (gst_uvc_h264_src_parse_event (self, self->vidsrc, event))
      return TRUE;
  
    return GST_ELEMENT_CLASS (parent_class)->send_event (element, event);
  }
  
  static gboolean
  gst_uvc_h264_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (GST_PAD_PARENT (pad));
  
    switch (GST_EVENT_TYPE (event)) {
      case GST_EVENT_SEGMENT:
        if (pad == self->vidsrc) {
          const GstSegment *s;
  
          gst_event_parse_segment (event, &s);
          gst_segment_copy_into (s, &self->segment);
        }
        break;
      case GST_EVENT_FLUSH_STOP:
        if (pad == self->vidsrc)
          gst_segment_init (&self->segment, GST_FORMAT_UNDEFINED);
        break;
      default:
        if (gst_uvc_h264_src_parse_event (self, pad, event))
          return TRUE;
        break;
    }
    return self->srcpad_event_func (pad, parent, event);
  }
  
  static guint8
  xu_get_id (GstUvcH264Src * self)
  {
    static const __u8 guid[16] = GUID_UVCX_H264_XU;
    GUdevClient *client;
    GUdevDevice *udevice;
    GUdevDevice *parent;
    guint64 busnum;
    guint64 devnum;
    libusb_device **device_list = NULL;
    libusb_device *device = NULL;
    ssize_t cnt;
    int i, j, k;
  
  
    if (self->usb_ctx == NULL)
      libusb_init (&self->usb_ctx);
  
    client = g_udev_client_new (NULL);
    if (client) {
      udevice = g_udev_client_query_by_device_file (client, self->device);
      if (udevice) {
        parent = g_udev_device_get_parent_with_subsystem (udevice, "usb",
            "usb_device");
        if (parent) {
          busnum = g_udev_device_get_sysfs_attr_as_uint64 (parent, "busnum");
          devnum = g_udev_device_get_sysfs_attr_as_uint64 (parent, "devnum");
  
          cnt = libusb_get_device_list (self->usb_ctx, &device_list);
          for (i = 0; i < cnt; i++) {
            if (busnum == libusb_get_bus_number (device_list[i]) &&
                devnum == libusb_get_device_address (device_list[i])) {
              device = libusb_ref_device (device_list[i]);
              break;
            }
          }
          libusb_free_device_list (device_list, 1);
          g_object_unref (parent);
        }
        g_object_unref (udevice);
      }
      g_object_unref (client);
    }
  
    if (device) {
      struct libusb_device_descriptor desc;
  
      if (libusb_get_device_descriptor (device, &desc) == 0) {
        for (i = 0; i < desc.bNumConfigurations; ++i) {
          struct libusb_config_descriptor *config = NULL;
  
          if (libusb_get_config_descriptor (device, i, &config) == 0) {
            for (j = 0; j < config->bNumInterfaces; j++) {
              for (k = 0; k < config->interface[j].num_altsetting; k++) {
                const struct libusb_interface_descriptor *interface;
                const guint8 *ptr = NULL;
  
                interface = &config->interface[j].altsetting[k];
                if (interface->bInterfaceClass != LIBUSB_CLASS_VIDEO ||
                    interface->bInterfaceSubClass != USB_VIDEO_CONTROL)
                  continue;
                ptr = interface->extra;
                while (ptr - interface->extra +
                    sizeof (xu_descriptor) < interface->extra_length) {
                  xu_descriptor *desc = (xu_descriptor *) ptr;
  
                  GST_DEBUG_OBJECT (self, "Found VideoControl interface with "
                      "unit id %d : %" GUID_FORMAT, desc->bUnitID,
                      GUID_ARGS (desc->guidExtensionCode));
                  if (desc->bDescriptorType == USB_VIDEO_CONTROL_INTERFACE &&
                      desc->bDescriptorSubType == USB_VIDEO_CONTROL_XU_TYPE &&
                      memcmp (desc->guidExtensionCode, guid, 16) == 0) {
                    guint8 unit_id = desc->bUnitID;
  
                    GST_DEBUG_OBJECT (self, "Found H264 XU unit : %d", unit_id);
  
                    libusb_free_config_descriptor (config);
                    libusb_unref_device (device);
                    return unit_id;
                  }
                  ptr += desc->bLength;
                }
              }
            }
            libusb_free_config_descriptor (config);
          }
        }
      }
      libusb_unref_device (device);
    }
  
    return 0;
  }
  
  static gboolean
  xu_query (GstUvcH264Src * self, guint selector, guint query, guchar * data)
  {
    struct uvc_xu_control_query xu;
    __u16 len;
  
    if (self->v4l2_fd == -1) {
      GST_WARNING_OBJECT (self, "Can't query XU with fd = -1");
      return FALSE;
    }
  
    xu.unit = self->h264_unit_id;
    xu.selector = selector;
  
    xu.query = UVC_GET_LEN;
    xu.size = sizeof (len);
    xu.data = (unsigned char *) &len;
    if (-1 == ioctl (self->v4l2_fd, UVCIOC_CTRL_QUERY, &xu)) {
      GST_WARNING_OBJECT (self, "PROBE GET_LEN error");
      return FALSE;
    }
  
    if (query == UVC_GET_LEN) {
      *((__u16 *) data) = len;
    } else {
      xu.query = query;
      xu.size = len;
      xu.data = data;
      if (-1 == ioctl (self->v4l2_fd, UVCIOC_CTRL_QUERY, &xu)) {
        return FALSE;
      }
    }
  
    return TRUE;
  }
  
  static void
  fill_probe_commit (GstUvcH264Src * self,
      uvcx_video_config_probe_commit_t * probe, guint32 frame_interval,
      guint32 width, guint32 height, guint32 profile,
      UvcH264StreamFormat stream_format)
  {
    probe->dwFrameInterval = frame_interval;
    probe->dwBitRate = self->initial_bitrate;
    probe->wWidth = width;
    probe->wHeight = height;
    probe->wSliceUnits = self->slice_units;
    probe->wSliceMode = self->slice_mode;
    probe->wProfile = profile;
    probe->wIFramePeriod = self->iframe_period;
    probe->bUsageType = self->usage_type;
    probe->bRateControlMode = self->rate_control;
    if (self->fixed_framerate)
      probe->bRateControlMode |= UVC_H264_RATECONTROL_FIXED_FRM_FLG;
    probe->bStreamFormat = stream_format;
    probe->bEntropyCABAC = self->entropy;
    probe->bTimestamp = self->enable_sei ?
        UVC_H264_TIMESTAMP_SEI_ENABLE : UVC_H264_TIMESTAMP_SEI_DISABLE;
    probe->bNumOfReorderFrames = self->num_reorder_frames;
    probe->bPreviewFlipped = self->preview_flipped ?
        UVC_H264_PREFLIPPED_HORIZONTAL : UVC_H264_PREFLIPPED_DISABLE;
    probe->wLeakyBucketSize = self->leaky_bucket_size;
  }
  
  static void
  print_probe_commit (GstUvcH264Src * self,
      uvcx_video_config_probe_commit_t * probe)
  {
    GST_DEBUG_OBJECT (self, "  Frame interval : %d *100ns",
        probe->dwFrameInterval);
    GST_DEBUG_OBJECT (self, "  Bit rate : %d", probe->dwBitRate);
    GST_DEBUG_OBJECT (self, "  Hints : %X", probe->bmHints);
    GST_DEBUG_OBJECT (self, "  Configuration index : %d",
        probe->wConfigurationIndex);
    GST_DEBUG_OBJECT (self, "  Width : %d", probe->wWidth);
    GST_DEBUG_OBJECT (self, "  Height : %d", probe->wHeight);
    GST_DEBUG_OBJECT (self, "  Slice units : %d", probe->wSliceUnits);
    GST_DEBUG_OBJECT (self, "  Slice mode : %X", probe->wSliceMode);
    GST_DEBUG_OBJECT (self, "  Profile : %X", probe->wProfile);
    GST_DEBUG_OBJECT (self, "  IFrame Period : %d ms", probe->wIFramePeriod);
    GST_DEBUG_OBJECT (self, "  Estimated video delay : %d ms",
        probe->wEstimatedVideoDelay);
    GST_DEBUG_OBJECT (self, "  Estimated max config delay : %d ms",
        probe->wEstimatedMaxConfigDelay);
    GST_DEBUG_OBJECT (self, "  Usage type : %X", probe->bUsageType);
    GST_DEBUG_OBJECT (self, "  Rate control mode : %X", probe->bRateControlMode);
    GST_DEBUG_OBJECT (self, "  Temporal scale mode : %X",
        probe->bTemporalScaleMode);
    GST_DEBUG_OBJECT (self, "  Spatial scale mode : %X",
        probe->bSpatialScaleMode);
    GST_DEBUG_OBJECT (self, "  SNR scale mode : %X", probe->bSNRScaleMode);
    GST_DEBUG_OBJECT (self, "  Stream mux option : %X", probe->bStreamMuxOption);
    GST_DEBUG_OBJECT (self, "  Stream Format : %X", probe->bStreamFormat);
    GST_DEBUG_OBJECT (self, "  Entropy CABAC : %X", probe->bEntropyCABAC);
    GST_DEBUG_OBJECT (self, "  Timestamp : %X", probe->bTimestamp);
    GST_DEBUG_OBJECT (self, "  Num of reorder frames : %d",
        probe->bNumOfReorderFrames);
    GST_DEBUG_OBJECT (self, "  Preview flipped : %X", probe->bPreviewFlipped);
    GST_DEBUG_OBJECT (self, "  View : %d", probe->bView);
    GST_DEBUG_OBJECT (self, "  Stream ID : %X", probe->bStreamID);
    GST_DEBUG_OBJECT (self, "  Spatial layer ratio : %f",
        ((probe->bSpatialLayerRatio & 0xF0) >> 4) +
        ((float) (probe->bSpatialLayerRatio & 0x0F)) / 16);
    GST_DEBUG_OBJECT (self, "  Leaky bucket size : %d ms",
        probe->wLeakyBucketSize);
  }
  
  static void
  configure_h264 (GstUvcH264Src * self, gint fd)
  {
    uvcx_video_config_probe_commit_t probe;
  
    /* Set the secondary format first, so the last SET_CUR will be for the
     * H264 format. This way, we can still get the static control values with
     * a GET_CUR. Otherwise all static properties will return 0 because that's
     * what the GET_CUR of the raw format returns.
     */
    if (self->secondary_format == UVC_H264_SRC_FORMAT_RAW) {
      memset (&probe, 0, sizeof (probe));
      probe.dwFrameInterval = self->secondary_frame_interval;
      probe.wWidth = self->secondary_width;
      probe.wHeight = self->secondary_height;
      probe.bStreamMuxOption = 5;
  
      GST_DEBUG_OBJECT (self, "RAW PROBE SET_CUR : ");
      print_probe_commit (self, &probe);
  
      if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR,
              (guchar *) & probe)) {
        GST_WARNING_OBJECT (self, "PROBE SET_CUR error");
        return;
      }
  
      if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR,
              (guchar *) & probe)) {
        GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
        return;
      }
      GST_DEBUG_OBJECT (self, "RAW PROBE GET_CUR : ");
      print_probe_commit (self, &probe);
  
      if (!xu_query (self, UVCX_VIDEO_CONFIG_COMMIT, UVC_SET_CUR,
              (guchar *) & probe)) {
        GST_WARNING_OBJECT (self, "COMMIT SET_CUR error");
        return;
      }
    }
    /* Print MIN/MAX/DEF probe values for debugging purposes */
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_MIN,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
      return;
    }
    GST_DEBUG_OBJECT (self, "PROBE GET_MIN : ");
    print_probe_commit (self, &probe);
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_MAX,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
      return;
    }
    GST_DEBUG_OBJECT (self, "PROBE GET_MAX : ");
    print_probe_commit (self, &probe);
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_DEF,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
      return;
    }
    GST_DEBUG_OBJECT (self, "PROBE GET_DEF : ");
    print_probe_commit (self, &probe);
  
    fill_probe_commit (self, &probe, self->main_frame_interval,
        self->main_width, self->main_height, self->main_profile,
        self->main_stream_format);
    if (self->secondary_format != UVC_H264_SRC_FORMAT_NONE)
      probe.bStreamMuxOption = 3;
    else
      probe.bStreamMuxOption = 0;
    probe.bmHints = UVC_H264_BMHINTS_RESOLUTION | UVC_H264_BMHINTS_PROFILE |
        UVC_H264_BMHINTS_FRAME_INTERVAL;
  
    GST_DEBUG_OBJECT (self, "PROBE SET_CUR : ");
    print_probe_commit (self, &probe);
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "PROBE SET_CUR error");
      return;
    }
  
    if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
      return;
    }
    GST_DEBUG_OBJECT (self, "PROBE GET_CUR : ");
    print_probe_commit (self, &probe);
  
    /* Must validate the settings accepted by the encoder */
    if (!xu_query (self, UVCX_VIDEO_CONFIG_COMMIT, UVC_SET_CUR,
            (guchar *) & probe)) {
      GST_WARNING_OBJECT (self, "COMMIT SET_CUR error");
      return;
    }
  }
  
  static void
  v4l2src_prepare_format (GstElement * v4l2src, gint fd, GstCaps * caps,
      gpointer user_data)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (user_data);
  
    if (self->main_format == UVC_H264_SRC_FORMAT_H264) {
      /* TODO: update static controls and g_object_notify those that changed */
      configure_h264 (self, fd);
  
      /* TODO: update dynamic controls on READY state */
      /* Configure dynamic controls */
      set_rate_control (self);
      update_rate_control (self);
      set_level_idc (self);
      update_level_idc_and_get_max_mbps (self);
      set_bitrate (self);
      update_bitrate (self);
      set_qp (self, QP_I_FRAME);
      update_qp (self, QP_I_FRAME);
      set_qp (self, QP_P_FRAME);
      update_qp (self, QP_P_FRAME);
      set_qp (self, QP_B_FRAME);
      update_qp (self, QP_B_FRAME);
      set_ltr (self);
      update_ltr (self);
    }
  }
  
  static gboolean
  _extract_caps_info (GstStructure * structure, guint16 * width, guint16 * height,
      guint32 * frame_interval)
  {
    gint w, h, fps_n, fps_d;
    gboolean ret = TRUE;
  
    ret &= gst_structure_get_int (structure, "width", &w);
    ret &= gst_structure_get_int (structure, "height", &h);
    ret &= gst_structure_get_fraction (structure, "framerate", &fps_n, &fps_d);
  
    if (ret) {
      *width = w;
      *height = h;
      /* Interval is in 100ns */
      *frame_interval = GST_TIME_AS_NSECONDS ((fps_d * GST_SECOND) / fps_n) / 100;
    }
  
    return ret;
  }
  
  static guint16
  _extract_profile (GstStructure * structure)
  {
    const gchar *profile_str;
    guint16 profile;
  
    profile = UVC_H264_PROFILE_HIGH;
    profile_str = gst_structure_get_string (structure, "profile");
    if (profile_str) {
      if (!strcmp (profile_str, "constrained-baseline")) {
        profile = UVC_H264_PROFILE_CONSTRAINED_BASELINE;
      } else if (!strcmp (profile_str, "baseline")) {
        profile = UVC_H264_PROFILE_BASELINE;
      } else if (!strcmp (profile_str, "main")) {
        profile = UVC_H264_PROFILE_MAIN;
      } else if (!strcmp (profile_str, "high")) {
        profile = UVC_H264_PROFILE_HIGH;
      }
    }
    return profile;
  }
  
  static UvcH264StreamFormat
  _extract_stream_format (GstStructure * structure)
  {
    const gchar *stream_format;
  
    stream_format = gst_structure_get_string (structure, "stream-format");
    if (stream_format) {
      if (!strcmp (stream_format, "avc"))
        return UVC_H264_STREAMFORMAT_NAL;
      else if (!strcmp (stream_format, "byte-stream"))
        return UVC_H264_STREAMFORMAT_ANNEXB;
    }
    return UVC_H264_STREAMFORMAT_ANNEXB;
  }
  
  static GstCaps *
  _transform_caps (GstUvcH264Src * self, GstCaps * caps, const gchar * name)
  {
    GstElement *el = gst_element_factory_make (name, NULL);
    GstElement *cf = gst_element_factory_make ("capsfilter", NULL);
    GstElement *fs = gst_element_factory_make ("fakesink", NULL);
    GstPad *sink;
    GstCaps *out_caps = NULL;
  
    if (!el || !cf || !fs) {
      if (el)
        gst_object_unref (el);
      if (cf)
        gst_object_unref (cf);
      if (fs)
        gst_object_unref (fs);
      goto done;
    }
  
    gst_element_set_locked_state (el, TRUE);
    gst_element_set_locked_state (cf, TRUE);
    gst_element_set_locked_state (fs, TRUE);
  
    if (!gst_bin_add (GST_BIN (self), el)) {
      gst_object_unref (el);
      gst_object_unref (cf);
      gst_object_unref (fs);
      goto done;
    }
    if (!gst_bin_add (GST_BIN (self), cf)) {
      gst_object_unref (cf);
      gst_object_unref (fs);
      gst_bin_remove (GST_BIN (self), el);
      goto done;
    }
    if (!gst_bin_add (GST_BIN (self), fs)) {
      gst_object_unref (fs);
      gst_bin_remove (GST_BIN (self), el);
      gst_bin_remove (GST_BIN (self), cf);
      goto done;
    }
  
    g_object_set (cf, "caps", caps, NULL);
  
    if (!gst_element_link (cf, fs))
      goto error_remove;
    if (!gst_element_link (el, cf))
      goto error_remove;
  
    sink = gst_element_get_static_pad (el, "sink");
    if (!sink)
      goto error_remove;
    GST_DEBUG_OBJECT (self, "Transforming: %" GST_PTR_FORMAT, caps);
  
    caps = gst_pad_query_caps (sink, NULL);
    gst_object_unref (sink);
  
    GST_DEBUG_OBJECT (self, "Result: %" GST_PTR_FORMAT, out_caps);
  
  error_remove:
    gst_bin_remove (GST_BIN (self), cf);
    gst_bin_remove (GST_BIN (self), el);
    gst_bin_remove (GST_BIN (self), fs);
  
  done:
    if (out_caps == NULL)
      out_caps = gst_caps_copy (caps);
  
    return out_caps;
  }
  
  static GstCaps *
  gst_uvc_h264_src_transform_caps (GstUvcH264Src * self, GstCaps * caps)
  {
    GstCaps *h264 = gst_caps_new_empty_simple ("video/x-h264");
    GstCaps *jpg = gst_caps_new_empty_simple ("image/jpeg");
    GstCaps *h264_caps = gst_caps_intersect (h264, caps);
    GstCaps *jpg_caps = gst_caps_intersect (jpg, caps);
  
    /* TODO: Keep caps order after transformation */
    caps = _transform_caps (self, caps, self->colorspace_name);
    caps = gst_caps_make_writable (caps);
  
    if (!gst_caps_is_empty (h264_caps)) {
      gst_caps_append (caps, h264_caps);
    } else {
      gst_caps_unref (h264_caps);
    }
  
    if (!gst_caps_is_empty (jpg_caps)) {
      gst_caps_append (caps, jpg_caps);
    } else {
      gst_caps_unref (jpg_caps);
    }
  
    gst_caps_unref (h264);
    gst_caps_unref (jpg);
  
    return caps;
  }
  
  static GstCaps *
  gst_uvc_h264_src_fixate_caps (GstUvcH264Src * self, GstPad * v4l_pad,
      GstCaps * v4l_caps, GstCaps * peer_caps, gboolean primary)
  {
    GstCaps *caps = NULL;
    GstCaps *icaps = NULL;
    GstCaps *tcaps = NULL;
    int i;
  
    if (v4l_caps == NULL || gst_caps_is_any (v4l_caps)) {
      GST_DEBUG_OBJECT (self, "v4l caps are invalid. not fixating");
      return NULL;
    }
  
    tcaps = gst_caps_intersect_full (peer_caps, v4l_caps,
        GST_CAPS_INTERSECT_FIRST);
    GST_DEBUG_OBJECT (self, "intersect: %" GST_PTR_FORMAT, tcaps);
    icaps = gst_caps_normalize (tcaps);
  
    /* Prefer the first caps we are compatible with that the peer proposed */
    for (i = 0; i < gst_caps_get_size (icaps); i++) {
      /* get intersection */
      GstCaps *ipcaps = gst_caps_copy_nth (icaps, i);
      GstStructure *s = gst_caps_get_structure (ipcaps, 0);
  
      GST_DEBUG_OBJECT (self, "Testing %s: %" GST_PTR_FORMAT,
          primary ? "primary" : "secondary", ipcaps);
      if (primary && gst_structure_has_name (s, "video/x-h264")) {
        uvcx_video_config_probe_commit_t probe;
        guint16 width;
        guint16 height;
        guint32 interval;
        guint16 profile;
        UvcH264StreamFormat stream_format;
  
        if (_extract_caps_info (s, &width, &height, &interval)) {
          profile = _extract_profile (s);
          stream_format = _extract_stream_format (s);
          fill_probe_commit (self, &probe, interval, width, height,
              profile, stream_format);
          probe.bmHints = UVC_H264_BMHINTS_RESOLUTION |
              UVC_H264_BMHINTS_PROFILE | UVC_H264_BMHINTS_FRAME_INTERVAL;
  
          if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR,
                  (guchar *) & probe)) {
            GST_WARNING_OBJECT (self, "PROBE SET_CUR error");
            return NULL;
          }
  
          if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR,
                  (guchar *) & probe)) {
            GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
            return NULL;
          }
          GST_DEBUG_OBJECT (self, "Probe gives us %d==%d, %d==%d, %d==%d",
              probe.wWidth, width, probe.wHeight, height,
              probe.bStreamFormat, stream_format);
          if (probe.wWidth == width && probe.wHeight == height &&
              probe.bStreamFormat == stream_format) {
            caps = ipcaps;
            break;
          }
        }
      } else if (!primary && self->main_format == UVC_H264_SRC_FORMAT_H264) {
        uvcx_video_config_probe_commit_t probe;
        guint16 width;
        guint16 height;
        guint32 interval;
  
        if (_extract_caps_info (s, &width, &height, &interval)) {
          if (gst_structure_has_name (s, "video/x-raw")) {
            guint8 mux = 0;
            const gchar *format = gst_structure_get_string (s, "format");
  
            if ((format = gst_structure_get_string (s, "format"))) {
              if (g_strcmp0 (format, "YUY2") == 0)
                mux = 4;
              else if (g_strcmp0 (format, "NV12") == 0)
                mux = 8;
            }
            if (mux != 0) {
              memset (&probe, 0, sizeof (probe));
              probe.dwFrameInterval = interval;
              probe.wWidth = width;
              probe.wHeight = height;
              probe.bStreamMuxOption = mux | 1;
              probe.bmHints = UVC_H264_BMHINTS_RESOLUTION |
                  UVC_H264_BMHINTS_PROFILE | UVC_H264_BMHINTS_FRAME_INTERVAL;
  
              if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_SET_CUR,
                      (guchar *) & probe)) {
                GST_WARNING_OBJECT (self, "PROBE SET_CUR error");
                return NULL;
              }
  
              if (!xu_query (self, UVCX_VIDEO_CONFIG_PROBE, UVC_GET_CUR,
                      (guchar *) & probe)) {
                GST_WARNING_OBJECT (self, "PROBE GET_CUR error");
                return NULL;
              }
              GST_DEBUG_OBJECT (self, "Probe gives us %d==%d, %d==%d, %d~=%d",
                  probe.wWidth, width, probe.wHeight, height,
                  probe.bStreamMuxOption, mux);
              if (probe.wWidth == width && probe.wHeight == height &&
                  (probe.bStreamMuxOption & mux) != 0) {
                caps = ipcaps;
                break;
              }
            }
          } else if (gst_structure_has_name (s, "image/jpeg")) {
            /* HACK ALERT:  No way of figuring this one out but it seems the
             * camera doesn't allow for h264 muxing and jpeg resolution higher
             * than 640x480 so we shouldn't allow it */
            if (width <= 640 && height <= 480) {
              caps = ipcaps;
              break;
            }
          }
        }
      } else {
        caps = ipcaps;
        break;
      }
      gst_caps_unref (ipcaps);
    }
  
    if (caps) {
      caps = gst_caps_make_writable (caps);
  
      /* now fixate */
      if (!gst_caps_is_empty (caps)) {
        caps = gst_caps_fixate (caps);
        GST_DEBUG_OBJECT (self, "fixated to: %" GST_PTR_FORMAT, caps);
      }
  
      if (gst_caps_is_empty (caps) || gst_caps_is_any (caps)) {
        gst_caps_unref (caps);
        caps = NULL;
      }
    }
  
    return caps;
  }
  
  static void
  gst_uvc_h264_src_destroy_pipeline (GstUvcH264Src * self, gboolean v4l2src)
  {
    GstIterator *iter = NULL;
    gboolean done;
  
    if (v4l2src && self->v4l2_src) {
      gst_bin_remove (GST_BIN (self), self->v4l2_src);
      gst_element_set_state (self->v4l2_src, GST_STATE_NULL);
      gst_object_unref (self->v4l2_src);
      self->v4l2_src = NULL;
      self->v4l2_fd = -1;
      self->h264_unit_id = 0;
    }
    if (self->mjpg_demux) {
      gst_bin_remove (GST_BIN (self), self->mjpg_demux);
      gst_element_set_state (self->mjpg_demux, GST_STATE_NULL);
      gst_object_unref (self->mjpg_demux);
      self->mjpg_demux = NULL;
    }
    if (self->jpeg_dec) {
      gst_bin_remove (GST_BIN (self), self->jpeg_dec);
      gst_element_set_state (self->jpeg_dec, GST_STATE_NULL);
      gst_object_unref (self->jpeg_dec);
      self->jpeg_dec = NULL;
    }
    if (self->vid_colorspace) {
      gst_bin_remove (GST_BIN (self), self->vid_colorspace);
      gst_element_set_state (self->vid_colorspace, GST_STATE_NULL);
      gst_object_unref (self->vid_colorspace);
      self->vid_colorspace = NULL;
    }
    if (self->vf_colorspace) {
      gst_bin_remove (GST_BIN (self), self->vf_colorspace);
      gst_element_set_state (self->vf_colorspace, GST_STATE_NULL);
      gst_object_unref (self->vf_colorspace);
      self->vf_colorspace = NULL;
    }
    iter = gst_bin_iterate_elements (GST_BIN (self));
    done = FALSE;
    while (!done) {
      GValue data = { 0, };
  
      switch (gst_iterator_next (iter, &data)) {
        case GST_ITERATOR_OK:
        {
          GstElement *child = g_value_get_object (&data);
          if (child != self->v4l2_src) {
            gst_bin_remove (GST_BIN (self), child);
            gst_element_set_state (child, GST_STATE_NULL);
          }
          g_value_reset (&data);
          break;
        }
        case GST_ITERATOR_RESYNC:
          gst_iterator_resync (iter);
          break;
        case GST_ITERATOR_ERROR:
          done = TRUE;
          break;
        case GST_ITERATOR_DONE:
          done = TRUE;
          break;
      }
    }
    gst_iterator_free (iter);
  }
  
  static gboolean
  ensure_v4l2src (GstUvcH264Src * self)
  {
    gchar *device = NULL;
    GstClock *v4l2_clock = NULL;
  
    if (self->v4l2_src == NULL) {
      /* Create v4l2 source and set it up */
      self->v4l2_src = gst_element_factory_make ("v4l2src", NULL);
      if (!self->v4l2_src || !gst_bin_add (GST_BIN (self), self->v4l2_src))
        goto error;
      gst_object_ref (self->v4l2_src);
      g_signal_connect (self->v4l2_src, "prepare-format",
          (GCallback) v4l2src_prepare_format, self);
    }
  
    g_object_get (self->v4l2_src, "device", &device, NULL);
    g_object_set (self->v4l2_src,
        "device", self->device, "num-buffers", self->num_buffers, NULL);
  
    v4l2_clock = gst_element_get_clock (self->v4l2_src);
  
    /* Set to NULL if the device changed */
    if (g_strcmp0 (device, self->device))
      gst_element_set_state (self->v4l2_src, GST_STATE_NULL);
    g_free (device);
  
    if (gst_element_set_state (self->v4l2_src, GST_STATE_READY) !=
        GST_STATE_CHANGE_SUCCESS) {
      GST_DEBUG_OBJECT (self, "Unable to set v4l2src to READY state");
      goto error_remove;
    }
  
    /* Set/Update the fd and unit id after we go to READY */
    g_object_get (self->v4l2_src, "device-fd", &self->v4l2_fd, NULL);
    self->h264_unit_id = xu_get_id (self);
  
    if (self->h264_unit_id == 0) {
      GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
          ("Device is not a valid UVC H264 camera"), (NULL));
      goto error_remove;
    }
  
    /* going to state READY makes v4l2src lose its reference to the clock */
    if (v4l2_clock) {
      gst_element_set_clock (self->v4l2_src, v4l2_clock);
      gst_element_set_base_time (self->v4l2_src,
          gst_element_get_base_time (GST_ELEMENT (self)));
      gst_object_unref (v4l2_clock);
    }
  
    return TRUE;
  
  error_remove:
    gst_element_set_state (self->v4l2_src, GST_STATE_NULL);
    gst_bin_remove (GST_BIN (self), self->v4l2_src);
  
  error:
    if (v4l2_clock)
      gst_object_unref (v4l2_clock);
    if (self->v4l2_src)
      gst_object_unref (self->v4l2_src);
    self->v4l2_src = NULL;
    self->v4l2_fd = -1;
    self->h264_unit_id = 0;
  
    return FALSE;
  }
  
  static gboolean
  gst_uvc_h264_src_construct_pipeline (GstBaseCameraSrc * bcamsrc)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (bcamsrc);
    GstIterator *iter = NULL;
    gboolean iter_done = FALSE;
    GstPad *vf_pad = NULL;
    GstCaps *vf_caps = NULL;
    GstStructure *vf_struct = NULL;
    GstPad *vid_pad = NULL;
    GstCaps *vid_caps = NULL;
    GstStructure *vid_struct = NULL;
    GstCaps *src_caps = NULL;
    GstPad *v4l_pad = NULL;
    GstCaps *v4l_caps = NULL;
    gboolean jpg2raw = FALSE;
  
    enum
    {
      RAW_NONE, ENCODED_NONE, NONE_RAW, NONE_ENCODED,
      H264_JPG, H264_RAW, H264_JPG2RAW, NONE_NONE,
      RAW_RAW, ENCODED_ENCODED,
    } type;
  
    GST_DEBUG_OBJECT (self, "Construct pipeline");
    self->reconfiguring = TRUE;
  
    if (self->v4l2_src) {
      uvcx_encoder_reset req = { 0 };
  
      if (!xu_query (self, UVCX_ENCODER_RESET, UVC_SET_CUR, (guchar *) & req))
        GST_WARNING_OBJECT (self, " UVCX_ENCODER_RESET SET_CUR error");
    }
  
    if (!ensure_v4l2src (self))
      goto error;
  
    gst_uvc_h264_src_destroy_pipeline (self, FALSE);
  
    /* Potentially unlink v4l2src to the ghost pads */
    gst_ghost_pad_set_target (GST_GHOST_PAD (self->vidsrc), NULL);
    gst_ghost_pad_set_target (GST_GHOST_PAD (self->vfsrc), NULL);
  
    if (gst_pad_is_linked (self->vfsrc))
      vf_caps = gst_pad_peer_query_caps (self->vfsrc, NULL);
    if (gst_pad_is_linked (self->vidsrc))
      vid_caps = gst_pad_peer_query_caps (self->vidsrc, NULL);
  
    GST_DEBUG_OBJECT (self, "vfsrc caps : %" GST_PTR_FORMAT, vf_caps);
    GST_DEBUG_OBJECT (self, "vidsrc caps : %" GST_PTR_FORMAT, vid_caps);
    if (!self->started) {
      GST_DEBUG_OBJECT (self, "video not started. Ignoring vidsrc caps");
      if (vid_caps)
        gst_caps_unref (vid_caps);
      vid_caps = NULL;
    }
  
    v4l_pad = gst_element_get_static_pad (self->v4l2_src, "src");
    v4l_caps = gst_pad_query_caps (v4l_pad, NULL);
    GST_DEBUG_OBJECT (self, "v4l2src caps : %" GST_PTR_FORMAT, v4l_caps);
    if (vid_caps) {
      GstCaps *trans_caps = gst_uvc_h264_src_transform_caps (self, vid_caps);
  
      gst_caps_unref (vid_caps);
      vid_caps = gst_uvc_h264_src_fixate_caps (self, v4l_pad, v4l_caps,
          trans_caps, TRUE);
      gst_caps_unref (trans_caps);
  
      if (vid_caps) {
        vid_struct = gst_caps_get_structure (vid_caps, 0);
      } else {
        GST_WARNING_OBJECT (self, "Could not negotiate vidsrc caps format");
        gst_object_unref (v4l_pad);
        gst_caps_unref (v4l_caps);
        goto error_remove;
      }
    }
    GST_DEBUG_OBJECT (self, "Fixated vidsrc caps : %" GST_PTR_FORMAT, vid_caps);
  
    if (vid_caps && gst_structure_has_name (vid_struct, "video/x-h264")) {
      self->main_format = UVC_H264_SRC_FORMAT_H264;
      if (!_extract_caps_info (vid_struct, &self->main_width,
              &self->main_height, &self->main_frame_interval)) {
        gst_object_unref (v4l_pad);
        gst_caps_unref (v4l_caps);
        goto error_remove;
      }
  
      self->main_stream_format = _extract_stream_format (vid_struct);
      self->main_profile = _extract_profile (vid_struct);
    } else {
      self->main_format = UVC_H264_SRC_FORMAT_NONE;
    }
  
    if (vf_caps) {
      GstCaps *trans_caps = gst_uvc_h264_src_transform_caps (self, vf_caps);
  
      gst_caps_unref (vf_caps);
      vf_caps = gst_uvc_h264_src_fixate_caps (self, v4l_pad, v4l_caps,
          trans_caps, FALSE);
  
      /* If we couldn't find a suitable vf cap, try the jpeg2raw pipeline */
      if (!vf_caps && self->main_format == UVC_H264_SRC_FORMAT_H264) {
        GstCaps *jpg_caps;
  
        jpg2raw = TRUE;
        jpg_caps = _transform_caps (self, trans_caps, self->jpeg_decoder_name);
  
        vf_caps = gst_uvc_h264_src_fixate_caps (self, v4l_pad, v4l_caps,
            jpg_caps, FALSE);
        gst_caps_unref (jpg_caps);
      }
      gst_caps_unref (trans_caps);
      if (vf_caps) {
        vf_struct = gst_caps_get_structure (vf_caps, 0);
      } else {
        GST_WARNING_OBJECT (self, "Could not negotiate vfsrc caps format");
        gst_object_unref (v4l_pad);
        gst_caps_unref (v4l_caps);
        goto error_remove;
      }
    }
    GST_DEBUG_OBJECT (self, "Fixated vfsrc caps : %" GST_PTR_FORMAT, vf_caps);
    gst_object_unref (v4l_pad);
    gst_caps_unref (v4l_caps);
  
    if (vf_caps && vid_caps &&
        !gst_structure_has_name (vid_struct, "video/x-h264")) {
      /* Allow for vfsrc+vidsrc to both be raw or jpeg */
      if (gst_structure_has_name (vid_struct, "image/jpeg") &&
          gst_structure_has_name (vf_struct, "image/jpeg")) {
        self->main_format = UVC_H264_SRC_FORMAT_JPG;
        self->secondary_format = UVC_H264_SRC_FORMAT_JPG;
        type = ENCODED_ENCODED;
      } else if (!gst_structure_has_name (vid_struct, "image/jpeg") &&
          !gst_structure_has_name (vf_struct, "image/jpeg")) {
        self->main_format = UVC_H264_SRC_FORMAT_RAW;
        self->secondary_format = UVC_H264_SRC_FORMAT_RAW;
        type = RAW_RAW;
      } else {
        goto error_remove;
      }
    } else if (vf_caps && vid_caps) {
      guint32 smallest_frame_interval;
  
      if (!_extract_caps_info (vf_struct, &self->secondary_width,
              &self->secondary_height, &self->secondary_frame_interval))
        goto error_remove;
  
      if (jpg2raw == FALSE && gst_structure_has_name (vf_struct, "image/jpeg")) {
        type = H264_JPG;
        self->secondary_format = UVC_H264_SRC_FORMAT_JPG;
      } else {
        if (jpg2raw) {
          type = H264_JPG2RAW;
          self->secondary_format = UVC_H264_SRC_FORMAT_JPG;
        } else {
          type = H264_RAW;
          self->secondary_format = UVC_H264_SRC_FORMAT_RAW;
        }
      }
      smallest_frame_interval = MIN (self->main_frame_interval,
          self->secondary_frame_interval);
      /* Just to avoid a potential division by zero, set interval to 30 fps */
      if (smallest_frame_interval == 0)
        smallest_frame_interval = 333333;
  
      /* Frame interval is in 100ns units */
      src_caps = gst_caps_new_simple ("image/jpeg",
          "width", G_TYPE_INT, self->secondary_width,
          "height", G_TYPE_INT, self->secondary_height,
          "framerate", GST_TYPE_FRACTION,
          NSEC_PER_SEC / smallest_frame_interval, 100, NULL);
    } else if (vf_caps || vid_caps) {
      self->secondary_format = UVC_H264_SRC_FORMAT_NONE;
      if (vid_struct && gst_structure_has_name (vid_struct, "video/x-h264")) {
        type = ENCODED_NONE;
      } else if (vid_struct && gst_structure_has_name (vid_struct, "image/jpeg")) {
        type = ENCODED_NONE;
        self->main_format = UVC_H264_SRC_FORMAT_JPG;
      } else if (vf_struct && gst_structure_has_name (vf_struct, "image/jpeg")) {
        type = NONE_ENCODED;
        self->secondary_format = UVC_H264_SRC_FORMAT_JPG;
      } else if (vid_struct) {
        type = RAW_NONE;
        self->main_format = UVC_H264_SRC_FORMAT_RAW;
      } else if (vf_struct) {
        type = NONE_RAW;
        self->secondary_format = UVC_H264_SRC_FORMAT_RAW;
      } else {
        g_assert_not_reached ();
        type = NONE_NONE;
        self->main_format = UVC_H264_SRC_FORMAT_NONE;
      }
    } else {
      type = NONE_NONE;
      self->main_format = UVC_H264_SRC_FORMAT_NONE;
      self->secondary_format = UVC_H264_SRC_FORMAT_NONE;
    }
  
    switch (type) {
      case NONE_NONE:
        GST_DEBUG_OBJECT (self, "None+None");
        vf_pad = gst_element_get_static_pad (self->v4l2_src, "src");
        break;
      case RAW_NONE:
        GST_DEBUG_OBJECT (self, "Raw+None");
        self->vid_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        if (!self->vid_colorspace ||
            !gst_bin_add (GST_BIN (self), self->vid_colorspace))
          goto error_remove;
        gst_object_ref (self->vid_colorspace);
        if (!gst_element_link (self->v4l2_src, self->vid_colorspace))
          goto error_remove_all;
        vid_pad = gst_element_get_static_pad (self->vid_colorspace, "src");
        break;
      case NONE_RAW:
        GST_DEBUG_OBJECT (self, "None+Raw");
        self->vf_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        if (!self->vf_colorspace ||
            !gst_bin_add (GST_BIN (self), self->vf_colorspace))
          goto error_remove;
        gst_object_ref (self->vf_colorspace);
        if (!gst_element_link (self->v4l2_src, self->vf_colorspace))
          goto error_remove_all;
        vf_pad = gst_element_get_static_pad (self->vf_colorspace, "src");
        break;
      case ENCODED_NONE:
        GST_DEBUG_OBJECT (self, "Encoded+None");
        vid_pad = gst_element_get_static_pad (self->v4l2_src, "src");
        break;
      case NONE_ENCODED:
        GST_DEBUG_OBJECT (self, "None+Encoded");
        vf_pad = gst_element_get_static_pad (self->v4l2_src, "src");
        break;
      case H264_JPG:
        GST_DEBUG_OBJECT (self, "H264+JPG");
        self->mjpg_demux = gst_element_factory_make ("uvch264mjpgdemux", NULL);
        if (!self->mjpg_demux || !gst_bin_add (GST_BIN (self), self->mjpg_demux))
          goto error_remove;
        gst_object_ref (self->mjpg_demux);
        g_object_set (self->mjpg_demux, "device-fd", self->v4l2_fd,
            "num-clock-samples", self->num_clock_samples, NULL);
        if (!gst_element_link_filtered (self->v4l2_src, self->mjpg_demux,
                src_caps))
          goto error_remove_all;
        vid_pad = gst_element_get_static_pad (self->mjpg_demux, "h264");
        vf_pad = gst_element_get_static_pad (self->mjpg_demux, "jpeg");
        break;
      case H264_RAW:
        GST_DEBUG_OBJECT (self, "H264+Raw");
        self->mjpg_demux = gst_element_factory_make ("uvch264mjpgdemux", NULL);
        self->vf_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        if (!self->mjpg_demux || !self->vf_colorspace)
          goto error_remove;
        if (!gst_bin_add (GST_BIN (self), self->mjpg_demux))
          goto error_remove;
        gst_object_ref (self->mjpg_demux);
        g_object_set (self->mjpg_demux, "device-fd", self->v4l2_fd,
            "num-clock-samples", self->num_clock_samples, NULL);
        if (!gst_bin_add (GST_BIN (self), self->vf_colorspace)) {
          gst_object_unref (self->vf_colorspace);
          self->vf_colorspace = NULL;
          goto error_remove_all;
        }
        gst_object_ref (self->vf_colorspace);
        if (!gst_element_link_filtered (self->v4l2_src, self->mjpg_demux,
                src_caps))
          goto error_remove_all;
        if (!gst_element_link_pads (self->mjpg_demux, "yuy2",
                self->vf_colorspace, "sink"))
          goto error_remove_all;
        vid_pad = gst_element_get_static_pad (self->mjpg_demux, "h264");
        vf_pad = gst_element_get_static_pad (self->vf_colorspace, "src");
        break;
      case H264_JPG2RAW:
        GST_DEBUG_OBJECT (self, "H264+Raw(jpegdec)");
        self->mjpg_demux = gst_element_factory_make ("uvch264mjpgdemux", NULL);
        self->jpeg_dec = gst_element_factory_make (self->jpeg_decoder_name, NULL);
        self->vf_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        if (!self->mjpg_demux || !self->jpeg_dec || !self->vf_colorspace)
          goto error_remove;
        if (!gst_bin_add (GST_BIN (self), self->mjpg_demux))
          goto error_remove;
        gst_object_ref (self->mjpg_demux);
        g_object_set (self->mjpg_demux, "device-fd", self->v4l2_fd,
            "num-clock-samples", self->num_clock_samples, NULL);
        if (!gst_bin_add (GST_BIN (self), self->jpeg_dec)) {
          gst_object_unref (self->jpeg_dec);
          self->jpeg_dec = NULL;
          gst_object_unref (self->vf_colorspace);
          self->vf_colorspace = NULL;
          goto error_remove_all;
        }
        gst_object_ref (self->jpeg_dec);
        if (!gst_bin_add (GST_BIN (self), self->vf_colorspace)) {
          gst_object_unref (self->vf_colorspace);
          self->vf_colorspace = NULL;
          goto error_remove_all;
        }
        gst_object_ref (self->vf_colorspace);
        if (!gst_element_link_filtered (self->v4l2_src, self->mjpg_demux,
                src_caps))
          goto error_remove_all;
        if (!gst_element_link_pads (self->mjpg_demux, "jpeg", self->jpeg_dec,
                "sink"))
          goto error_remove_all;
        if (!gst_element_link (self->jpeg_dec, self->vf_colorspace))
          goto error_remove_all;
        vid_pad = gst_element_get_static_pad (self->mjpg_demux, "h264");
        vf_pad = gst_element_get_static_pad (self->vf_colorspace, "src");
        break;
      case RAW_RAW:
      {
        GstElement *tee = NULL;
  
        GST_DEBUG_OBJECT (self, "Raw+Raw");
        tee = gst_element_factory_make ("tee", NULL);
        if (!tee || !gst_bin_add (GST_BIN (self), tee)) {
          if (tee)
            gst_object_unref (tee);
          goto error_remove;
        }
        self->vf_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        self->vid_colorspace = gst_element_factory_make (self->colorspace_name,
            NULL);
        if (!self->vf_colorspace || !self->vid_colorspace)
          goto error_remove;
        if (!gst_bin_add (GST_BIN (self), self->vf_colorspace))
          goto error_remove;
        gst_object_ref (self->vf_colorspace);
        if (!gst_bin_add (GST_BIN (self), self->vid_colorspace)) {
          gst_object_unref (self->vid_colorspace);
          self->vid_colorspace = NULL;
          goto error_remove_all;
        }
        gst_object_ref (self->vid_colorspace);
        if (!gst_element_link (self->v4l2_src, tee))
          goto error_remove_all;
        if (!gst_element_link (tee, self->vf_colorspace))
          goto error_remove_all;
        if (!gst_element_link (tee, self->vid_colorspace))
          goto error_remove_all;
        vf_pad = gst_element_get_static_pad (self->vf_colorspace, "src");
        vid_pad = gst_element_get_static_pad (self->vid_colorspace, "src");
      }
        break;
      case ENCODED_ENCODED:
      {
        GstElement *tee = NULL;
  
        GST_DEBUG_OBJECT (self, "Encoded+Encoded");
        tee = gst_element_factory_make ("tee", NULL);
        if (!tee || !gst_bin_add (GST_BIN (self), tee)) {
          if (tee)
            gst_object_unref (tee);
          goto error_remove;
        }
        if (!gst_element_link (self->v4l2_src, tee))
          goto error_remove_all;
        vf_pad = gst_element_get_request_pad (tee, "src_%u");
        vid_pad = gst_element_get_request_pad (tee, "src_%u");
      }
        break;
    }
  
    if (!gst_ghost_pad_set_target (GST_GHOST_PAD (self->vidsrc), vid_pad) ||
        !gst_ghost_pad_set_target (GST_GHOST_PAD (self->vfsrc), vf_pad))
      goto error_remove_all;
    if (vid_pad)
      gst_object_unref (vid_pad);
    if (vf_pad)
      gst_object_unref (vf_pad);
    vid_pad = vf_pad = NULL;
  
    if (vf_caps)
      gst_caps_unref (vf_caps);
    if (vid_caps)
      gst_caps_unref (vid_caps);
    if (src_caps)
      gst_caps_unref (src_caps);
    vf_caps = vid_caps = src_caps = NULL;
  
    /* Sync children states, in sink to source order */
    if (self->vid_colorspace &&
        !gst_element_sync_state_with_parent (self->vid_colorspace))
      goto error_remove_all;
    if (self->vf_colorspace &&
        !gst_element_sync_state_with_parent (self->vf_colorspace))
      goto error_remove_all;
    if (self->jpeg_dec && !gst_element_sync_state_with_parent (self->jpeg_dec))
      goto error_remove_all;
    if (self->mjpg_demux &&
        !gst_element_sync_state_with_parent (self->mjpg_demux))
      goto error_remove_all;
    if (self->v4l2_src && !gst_element_sync_state_with_parent (self->v4l2_src))
      goto error_remove_all;
  
    /* Sync any remaining children states with bin's state */
    iter = gst_bin_iterate_elements (GST_BIN (self));
    iter_done = FALSE;
    while (!iter_done) {
      GstElement *child = NULL;
      GValue data = { 0, };
  
      switch (gst_iterator_next (iter, &data)) {
        case GST_ITERATOR_OK:
          child = g_value_get_object (&data);
          if (!gst_element_sync_state_with_parent (child)) {
            g_value_reset (&data);
            gst_iterator_free (iter);
            goto error_remove_all;
          }
          g_value_reset (&data);
          break;
        case GST_ITERATOR_RESYNC:
          gst_iterator_resync (iter);
          break;
        case GST_ITERATOR_ERROR:
          iter_done = TRUE;
          break;
        case GST_ITERATOR_DONE:
          iter_done = TRUE;
          break;
      }
    }
    gst_iterator_free (iter);
  
    self->reconfiguring = FALSE;
    return TRUE;
  
  error_remove_all:
    gst_uvc_h264_src_destroy_pipeline (self, FALSE);
  error_remove:
    gst_element_set_state (self->v4l2_src, GST_STATE_NULL);
    gst_bin_remove (GST_BIN (self), self->v4l2_src);
  
  error:
    if (self->v4l2_src)
      gst_object_unref (self->v4l2_src);
    self->v4l2_src = NULL;
    self->v4l2_fd = -1;
    self->h264_unit_id = 0;
  
    if (self->mjpg_demux)
      gst_object_unref (self->mjpg_demux);
    self->mjpg_demux = NULL;
    if (self->jpeg_dec)
      gst_object_unref (self->jpeg_dec);
    self->jpeg_dec = NULL;
    if (self->vid_colorspace)
      gst_object_unref (self->vid_colorspace);
    self->vid_colorspace = NULL;
    if (self->vf_colorspace)
      gst_object_unref (self->vf_colorspace);
    self->vf_colorspace = NULL;
  
    if (src_caps)
      gst_caps_unref (src_caps);
  
    if (vf_caps)
      gst_caps_unref (vf_caps);
    if (vid_caps)
      gst_caps_unref (vid_caps);
  
    if (vid_pad)
      gst_object_unref (vid_pad);
    if (vf_pad)
      gst_object_unref (vf_pad);
  
    self->reconfiguring = FALSE;
    return FALSE;
  }
  
  static GstCaps *
  gst_uvc_h264_src_getcaps (GstPad * pad, GstObject * parent, GstQuery * query)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (parent);
    GstCaps *template = NULL;
    GstCaps *result = NULL;
  
    if (pad == self->vfsrc)
      template = gst_static_pad_template_get_caps (&vfsrc_template);
    else if (pad == self->vidsrc)
      template = gst_static_pad_template_get_caps (&vidsrc_template);
    else
      template = gst_caps_new_empty ();
  
    if (self->v4l2_src) {
      GstCaps *filter;
      GstPad *v4l_pad = gst_element_get_static_pad (self->v4l2_src, "src");
      GstCaps *v4l_caps = NULL;
      GstCaps *new_caps = NULL;
  
      gst_query_parse_caps (query, &filter);
      v4l_caps = gst_pad_query_caps (v4l_pad, filter);
      new_caps = gst_uvc_h264_src_transform_caps (self, v4l_caps);
  
      result = gst_caps_intersect (new_caps, template);
      gst_object_unref (v4l_pad);
      gst_caps_unref (v4l_caps);
      gst_caps_unref (new_caps);
      gst_caps_unref (template);
    } else {
      result = template;
    }
  
    return result;
  }
  
  static gboolean
  gst_uvc_h264_src_query (GstPad * pad, GstObject * parent, GstQuery * query)
  {
    gboolean ret;
  
    switch (GST_QUERY_TYPE (query)) {
      case GST_QUERY_CAPS:{
        GstCaps *caps;
  
        caps = gst_uvc_h264_src_getcaps (pad, parent, query);
        gst_query_set_caps_result (query, caps);
        gst_caps_unref (caps);
        ret = TRUE;
        break;
      }
      default:
        ret = gst_pad_query_default (pad, parent, query);
        break;
    }
    return ret;
  }
  
  
  static gboolean
  gst_uvc_h264_src_set_mode (GstBaseCameraSrc * bcamsrc, GstCameraBinMode mode)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (bcamsrc);
  
    GST_DEBUG_OBJECT (self, "set mode to %d", mode);
  
    return (mode == MODE_VIDEO);
  }
  
  static gboolean
  gst_uvc_h264_src_start_capture (GstBaseCameraSrc * camerasrc)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (camerasrc);
    gboolean ret = TRUE;
  
    GST_DEBUG_OBJECT (self, "start capture");
  
    if (!self->started) {
      self->started = TRUE;
      if (GST_STATE (self) >= GST_STATE_READY) {
        ret = gst_uvc_h264_src_construct_pipeline (GST_BASE_CAMERA_SRC (self));
        if (!ret) {
          GST_DEBUG_OBJECT (self, "Could not start capture");
          self->started = FALSE;
          gst_uvc_h264_src_construct_pipeline (GST_BASE_CAMERA_SRC (self));
        }
      }
    }
  
    return ret;
  }
  
  static void
  gst_uvc_h264_src_stop_capture (GstBaseCameraSrc * camerasrc)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (camerasrc);
  
    GST_DEBUG_OBJECT (self, "stop capture");
  
    if (self->started) {
      self->started = FALSE;
      if (GST_STATE (self) >= GST_STATE_READY)
        gst_uvc_h264_src_construct_pipeline (GST_BASE_CAMERA_SRC (self));
      gst_base_camera_src_finish_capture (camerasrc);
    }
  }
  
  static void
  gst_uvc_h264_src_pad_linking_cb (GstPad * pad,
      GstPad * peer, gpointer user_data)
  {
    GstUvcH264Src *self = GST_UVC_H264_SRC (user_data);
    gchar *pad_name = gst_pad_get_name (pad);
  
    GST_DEBUG_OBJECT (self, "Pad %s was (un)linked. Renegotiating", pad_name);
    g_free (pad_name);
    if (GST_STATE (self) >= GST_STATE_READY)
      gst_uvc_h264_src_construct_pipeline (GST_BASE_CAMERA_SRC (self));
  }
  
  
  static GstStateChangeReturn
  gst_uvc_h264_src_change_state (GstElement * element, GstStateChange trans)
  {
    GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
    GstUvcH264Src *self = GST_UVC_H264_SRC (element);
  
    switch (trans) {
      case GST_STATE_CHANGE_NULL_TO_READY:
        if (!ensure_v4l2src (self)) {
          ret = GST_STATE_CHANGE_FAILURE;
          goto end;
        }
        gst_segment_init (&self->segment, GST_FORMAT_UNDEFINED);
        break;
      case GST_STATE_CHANGE_READY_TO_PAUSED:
      case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
        if (!self->v4l2_src)
          gst_uvc_h264_src_construct_pipeline (GST_BASE_CAMERA_SRC (self));
        break;
      default:
        break;
    }
  
    ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, trans);
  
    if (ret == GST_STATE_CHANGE_FAILURE)
      goto end;
  
    switch (trans) {
      case GST_STATE_CHANGE_READY_TO_NULL:
        gst_uvc_h264_src_destroy_pipeline (self, TRUE);
        break;
      default:
        break;
    }
  
  
  end:
    return ret;
  }
  