text: /*
   *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
   *
   *  Use of this source code is governed by a BSD-style license
   *  that can be found in the LICENSE file in the root of the source
   *  tree. An additional intellectual property rights grant can be found
   *  in the file PATENTS.  All contributing project authors may
   *  be found in the AUTHORS file in the root of the source tree.
   */
  
  #ifndef VP9_ENCODER_VP9_SVC_LAYERCONTEXT_H_
  #define VP9_ENCODER_VP9_SVC_LAYERCONTEXT_H_
  
  #include "vpx/vpx_encoder.h"
  
  #include "vp9/encoder/vp9_ratectrl.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  typedef struct {
    RATE_CONTROL rc;
    int target_bandwidth;
    int spatial_layer_target_bandwidth;  // Target for the spatial layer.
    double framerate;
    int avg_frame_size;
    int max_q;
    int min_q;
    int scaling_factor_num;
    int scaling_factor_den;
    TWO_PASS twopass;
    vpx_fixed_buf_t rc_twopass_stats_in;
    unsigned int current_video_frame_in_layer;
    int is_key_frame;
    int frames_from_key_frame;
    FRAME_TYPE last_frame_type;
    struct lookahead_entry *alt_ref_source;
    int alt_ref_idx;
    int gold_ref_idx;
    int has_alt_frame;
    size_t layer_size;
    struct vpx_psnr_pkt psnr_pkt;
    // Cyclic refresh parameters (aq-mode=3), that need to be updated per-frame.
    int sb_index;
    signed char *map;
    uint8_t *last_coded_q_map;
    uint8_t *consec_zero_mv;
    uint8_t speed;
  } LAYER_CONTEXT;
  
  typedef struct SVC {
    int spatial_layer_id;
    int temporal_layer_id;
    int number_spatial_layers;
    int number_temporal_layers;
  
    int spatial_layer_to_encode;
    int first_spatial_layer_to_encode;
    int rc_drop_superframe;
  
    // Workaround for multiple frame contexts
    enum { ENCODED = 0, ENCODING, NEED_TO_ENCODE } encode_empty_frame_state;
    struct lookahead_entry empty_frame;
    int encode_intra_empty_frame;
  
    // Store scaled source frames to be used for temporal filter to generate
    // a alt ref frame.
    YV12_BUFFER_CONFIG scaled_frames[MAX_LAG_BUFFERS];
    // Temp buffer used for 2-stage down-sampling, for real-time mode.
    YV12_BUFFER_CONFIG scaled_temp;
    int scaled_one_half;
    int scaled_temp_is_alloc;
  
    // Layer context used for rate control in one pass temporal CBR mode or
    // two pass spatial mode.
    LAYER_CONTEXT layer_context[VPX_MAX_LAYERS];
    // Indicates what sort of temporal layering is used.
    // Currently, this only works for CBR mode.
    VP9E_TEMPORAL_LAYERING_MODE temporal_layering_mode;
    // Frame flags and buffer indexes for each spatial layer, set by the
    // application (external settings).
    int ext_frame_flags[VPX_MAX_LAYERS];
    int ext_lst_fb_idx[VPX_MAX_LAYERS];
    int ext_gld_fb_idx[VPX_MAX_LAYERS];
    int ext_alt_fb_idx[VPX_MAX_LAYERS];
    int ref_frame_index[REF_FRAMES];
    int force_zero_mode_spatial_ref;
    int current_superframe;
    int non_reference_frame;
    int use_base_mv;
    // Used to control the downscaling filter for source scaling, for 1 pass CBR.
    // downsample_filter_phase: = 0 will do sub-sampling (no weighted average),
    // = 8 will center the target pixel and get a symmetric averaging filter.
    // downsample_filter_type: 4 filters may be used: eighttap_regular,
    // eighttap_smooth, eighttap_sharp, and bilinear.
    INTERP_FILTER downsample_filter_type[VPX_SS_MAX_LAYERS];
    int downsample_filter_phase[VPX_SS_MAX_LAYERS];
  
    BLOCK_SIZE *prev_partition_svc;
    int mi_stride[VPX_MAX_LAYERS];
  
    int first_layer_denoise;
  } SVC;
  
  struct VP9_COMP;
  
  // Initialize layer context data from init_config().
  void vp9_init_layer_context(struct VP9_COMP *const cpi);
  
  // Update the layer context from a change_config() call.
  void vp9_update_layer_context_change_config(struct VP9_COMP *const cpi,
                                              const int target_bandwidth);
  
  // Prior to encoding the frame, update framerate-related quantities
  // for the current temporal layer.
  void vp9_update_temporal_layer_framerate(struct VP9_COMP *const cpi);
  
  // Update framerate-related quantities for the current spatial layer.
  void vp9_update_spatial_layer_framerate(struct VP9_COMP *const cpi,
                                          double framerate);
  
  // Prior to encoding the frame, set the layer context, for the current layer
  // to be encoded, to the cpi struct.
  void vp9_restore_layer_context(struct VP9_COMP *const cpi);
  
  // Save the layer context after encoding the frame.
  void vp9_save_layer_context(struct VP9_COMP *const cpi);
  
  // Initialize second pass rc for spatial svc.
  void vp9_init_second_pass_spatial_svc(struct VP9_COMP *cpi);
  
  void get_layer_resolution(const int width_org, const int height_org,
                            const int num, const int den, int *width_out,
                            int *height_out);
  
  // Increment number of video frames in layer
  void vp9_inc_frame_in_layer(struct VP9_COMP *const cpi);
  
  // Check if current layer is key frame in spatial upper layer
  int vp9_is_upper_layer_key_frame(const struct VP9_COMP *const cpi);
  
  // Get the next source buffer to encode
  struct lookahead_entry *vp9_svc_lookahead_pop(struct VP9_COMP *const cpi,
                                                struct lookahead_ctx *ctx,
                                                int drain);
  
  // Start a frame and initialize svc parameters
  int vp9_svc_start_frame(struct VP9_COMP *const cpi);
  
  int vp9_one_pass_cbr_svc_start_layer(struct VP9_COMP *const cpi);
  
  void vp9_free_svc_cyclic_refresh(struct VP9_COMP *const cpi);
  
  void vp9_svc_reset_key_frame(struct VP9_COMP *const cpi);
  
  void vp9_svc_check_reset_layer_rc_flag(struct VP9_COMP *const cpi);
  
  #ifdef __cplusplus
  }  // extern "C"
  #endif
  
  #endif  // VP9_ENCODER_VP9_SVC_LAYERCONTEXT_
  