text: /*
   * HEVC video decoder
   *
   * Copyright (C) 2012 - 2013 Guillaume Martres
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  #ifndef AVCODEC_HEVC_H
  #define AVCODEC_HEVC_H
  
  #include "libavutil/buffer.h"
  #include "libavutil/md5.h"
  
  #include "avcodec.h"
  #include "bswapdsp.h"
  #include "cabac.h"
  #include "get_bits.h"
  #include "hevcpred.h"
  #include "hevcdsp.h"
  #include "internal.h"
  #include "thread.h"
  #include "videodsp.h"
  
  #define MAX_DPB_SIZE 16 // A.4.1
  #define MAX_REFS 16
  
  #define MAX_NB_THREADS 16
  #define SHIFT_CTB_WPP 2
  
  /**
   * 7.4.2.1
   */
  #define MAX_SUB_LAYERS 7
  #define MAX_VPS_COUNT 16
  #define MAX_SPS_COUNT 32
  #define MAX_PPS_COUNT 256
  #define MAX_SHORT_TERM_RPS_COUNT 64
  #define MAX_CU_SIZE 128
  
  //TODO: check if this is really the maximum
  #define MAX_TRANSFORM_DEPTH 5
  
  #define MAX_TB_SIZE 32
  #define MAX_LOG2_CTB_SIZE 6
  #define MAX_QP 51
  #define DEFAULT_INTRA_TC_OFFSET 2
  
  #define HEVC_CONTEXTS 199
  
  #define MRG_MAX_NUM_CANDS     5
  
  #define L0 0
  #define L1 1
  
  #define EPEL_EXTRA_BEFORE 1
  #define EPEL_EXTRA_AFTER  2
  #define EPEL_EXTRA        3
  #define QPEL_EXTRA_BEFORE 3
  #define QPEL_EXTRA_AFTER  4
  #define QPEL_EXTRA        7
  
  #define EDGE_EMU_BUFFER_STRIDE 80
  
  /**
   * Value of the luma sample at position (x, y) in the 2D array tab.
   */
  #define SAMPLE(tab, x, y) ((tab)[(y) * s->sps->width + (x)])
  #define SAMPLE_CTB(tab, x, y) ((tab)[(y) * min_cb_width + (x)])
  
  #define IS_IDR(s) ((s)->nal_unit_type == NAL_IDR_W_RADL || (s)->nal_unit_type == NAL_IDR_N_LP)
  #define IS_BLA(s) ((s)->nal_unit_type == NAL_BLA_W_RADL || (s)->nal_unit_type == NAL_BLA_W_LP || \
                     (s)->nal_unit_type == NAL_BLA_N_LP)
  #define IS_IRAP(s) ((s)->nal_unit_type >= 16 && (s)->nal_unit_type <= 23)
  
  /**
   * Table 7-3: NAL unit type codes
   */
  enum NALUnitType {
      NAL_TRAIL_N    = 0,
      NAL_TRAIL_R    = 1,
      NAL_TSA_N      = 2,
      NAL_TSA_R      = 3,
      NAL_STSA_N     = 4,
      NAL_STSA_R     = 5,
      NAL_RADL_N     = 6,
      NAL_RADL_R     = 7,
      NAL_RASL_N     = 8,
      NAL_RASL_R     = 9,
      NAL_BLA_W_LP   = 16,
      NAL_BLA_W_RADL = 17,
      NAL_BLA_N_LP   = 18,
      NAL_IDR_W_RADL = 19,
      NAL_IDR_N_LP   = 20,
      NAL_CRA_NUT    = 21,
      NAL_VPS        = 32,
      NAL_SPS        = 33,
      NAL_PPS        = 34,
      NAL_AUD        = 35,
      NAL_EOS_NUT    = 36,
      NAL_EOB_NUT    = 37,
      NAL_FD_NUT     = 38,
      NAL_SEI_PREFIX = 39,
      NAL_SEI_SUFFIX = 40,
  };
  
  enum RPSType {
      ST_CURR_BEF = 0,
      ST_CURR_AFT,
      ST_FOLL,
      LT_CURR,
      LT_FOLL,
      NB_RPS_TYPE,
  };
  
  enum SliceType {
      B_SLICE = 0,
      P_SLICE = 1,
      I_SLICE = 2,
  };
  
  enum SyntaxElement {
      SAO_MERGE_FLAG = 0,
      SAO_TYPE_IDX,
      SAO_EO_CLASS,
      SAO_BAND_POSITION,
      SAO_OFFSET_ABS,
      SAO_OFFSET_SIGN,
      END_OF_SLICE_FLAG,
      SPLIT_CODING_UNIT_FLAG,
      CU_TRANSQUANT_BYPASS_FLAG,
      SKIP_FLAG,
      CU_QP_DELTA,
      PRED_MODE_FLAG,
      PART_MODE,
      PCM_FLAG,
      PREV_INTRA_LUMA_PRED_FLAG,
      MPM_IDX,
      REM_INTRA_LUMA_PRED_MODE,
      INTRA_CHROMA_PRED_MODE,
      MERGE_FLAG,
      MERGE_IDX,
      INTER_PRED_IDC,
      REF_IDX_L0,
      REF_IDX_L1,
      ABS_MVD_GREATER0_FLAG,
      ABS_MVD_GREATER1_FLAG,
      ABS_MVD_MINUS2,
      MVD_SIGN_FLAG,
      MVP_LX_FLAG,
      NO_RESIDUAL_DATA_FLAG,
      SPLIT_TRANSFORM_FLAG,
      CBF_LUMA,
      CBF_CB_CR,
      TRANSFORM_SKIP_FLAG,
      EXPLICIT_RDPCM_FLAG,
      EXPLICIT_RDPCM_DIR_FLAG,
      LAST_SIGNIFICANT_COEFF_X_PREFIX,
      LAST_SIGNIFICANT_COEFF_Y_PREFIX,
      LAST_SIGNIFICANT_COEFF_X_SUFFIX,
      LAST_SIGNIFICANT_COEFF_Y_SUFFIX,
      SIGNIFICANT_COEFF_GROUP_FLAG,
      SIGNIFICANT_COEFF_FLAG,
      COEFF_ABS_LEVEL_GREATER1_FLAG,
      COEFF_ABS_LEVEL_GREATER2_FLAG,
      COEFF_ABS_LEVEL_REMAINING,
      COEFF_SIGN_FLAG,
      LOG2_RES_SCALE_ABS,
      RES_SCALE_SIGN_FLAG,
      CU_CHROMA_QP_OFFSET_FLAG,
      CU_CHROMA_QP_OFFSET_IDX,
  };
  
  enum PartMode {
      PART_2Nx2N = 0,
      PART_2NxN  = 1,
      PART_Nx2N  = 2,
      PART_NxN   = 3,
      PART_2NxnU = 4,
      PART_2NxnD = 5,
      PART_nLx2N = 6,
      PART_nRx2N = 7,
  };
  
  enum PredMode {
      MODE_INTER = 0,
      MODE_INTRA,
      MODE_SKIP,
  };
  
  enum InterPredIdc {
      PRED_L0 = 0,
      PRED_L1,
      PRED_BI,
  };
  
  enum PredFlag {
      PF_INTRA = 0,
      PF_L0,
      PF_L1,
      PF_BI,
  };
  
  enum IntraPredMode {
      INTRA_PLANAR = 0,
      INTRA_DC,
      INTRA_ANGULAR_2,
      INTRA_ANGULAR_3,
      INTRA_ANGULAR_4,
      INTRA_ANGULAR_5,
      INTRA_ANGULAR_6,
      INTRA_ANGULAR_7,
      INTRA_ANGULAR_8,
      INTRA_ANGULAR_9,
      INTRA_ANGULAR_10,
      INTRA_ANGULAR_11,
      INTRA_ANGULAR_12,
      INTRA_ANGULAR_13,
      INTRA_ANGULAR_14,
      INTRA_ANGULAR_15,
      INTRA_ANGULAR_16,
      INTRA_ANGULAR_17,
      INTRA_ANGULAR_18,
      INTRA_ANGULAR_19,
      INTRA_ANGULAR_20,
      INTRA_ANGULAR_21,
      INTRA_ANGULAR_22,
      INTRA_ANGULAR_23,
      INTRA_ANGULAR_24,
      INTRA_ANGULAR_25,
      INTRA_ANGULAR_26,
      INTRA_ANGULAR_27,
      INTRA_ANGULAR_28,
      INTRA_ANGULAR_29,
      INTRA_ANGULAR_30,
      INTRA_ANGULAR_31,
      INTRA_ANGULAR_32,
      INTRA_ANGULAR_33,
      INTRA_ANGULAR_34,
  };
  
  enum SAOType {
      SAO_NOT_APPLIED = 0,
      SAO_BAND,
      SAO_EDGE,
      SAO_APPLIED
  };
  
  enum SAOEOClass {
      SAO_EO_HORIZ = 0,
      SAO_EO_VERT,
      SAO_EO_135D,
      SAO_EO_45D,
  };
  
  enum ScanType {
      SCAN_DIAG = 0,
      SCAN_HORIZ,
      SCAN_VERT,
  };
  
  typedef struct ShortTermRPS {
      unsigned int num_negative_pics;
      int num_delta_pocs;
      int rps_idx_num_delta_pocs;
      int32_t delta_poc[32];
      uint8_t used[32];
  } ShortTermRPS;
  
  typedef struct LongTermRPS {
      int     poc[32];
      uint8_t used[32];
      uint8_t nb_refs;
  } LongTermRPS;
  
  typedef struct RefPicList {
      struct HEVCFrame *ref[MAX_REFS];
      int list[MAX_REFS];
      int isLongTerm[MAX_REFS];
      int nb_refs;
  } RefPicList;
  
  typedef struct RefPicListTab {
      RefPicList refPicList[2];
  } RefPicListTab;
  
  typedef struct HEVCWindow {
      unsigned int left_offset;
      unsigned int right_offset;
      unsigned int top_offset;
      unsigned int bottom_offset;
  } HEVCWindow;
  
  typedef struct VUI {
      AVRational sar;
  
      int overscan_info_present_flag;
      int overscan_appropriate_flag;
  
      int video_signal_type_present_flag;
      int video_format;
      int video_full_range_flag;
      int colour_description_present_flag;
      uint8_t colour_primaries;
      uint8_t transfer_characteristic;
      uint8_t matrix_coeffs;
  
      int chroma_loc_info_present_flag;
      int chroma_sample_loc_type_top_field;
      int chroma_sample_loc_type_bottom_field;
      int neutra_chroma_indication_flag;
  
      int field_seq_flag;
      int frame_field_info_present_flag;
  
      int default_display_window_flag;
      HEVCWindow def_disp_win;
  
      int vui_timing_info_present_flag;
      uint32_t vui_num_units_in_tick;
      uint32_t vui_time_scale;
      int vui_poc_proportional_to_timing_flag;
      int vui_num_ticks_poc_diff_one_minus1;
      int vui_hrd_parameters_present_flag;
  
      int bitstream_restriction_flag;
      int tiles_fixed_structure_flag;
      int motion_vectors_over_pic_boundaries_flag;
      int restricted_ref_pic_lists_flag;
      int min_spatial_segmentation_idc;
      int max_bytes_per_pic_denom;
      int max_bits_per_min_cu_denom;
      int log2_max_mv_length_horizontal;
      int log2_max_mv_length_vertical;
  } VUI;
  
  typedef struct PTLCommon {
      uint8_t profile_space;
      uint8_t tier_flag;
      uint8_t profile_idc;
      uint8_t profile_compatibility_flag[32];
      uint8_t level_idc;
      uint8_t progressive_source_flag;
      uint8_t interlaced_source_flag;
      uint8_t non_packed_constraint_flag;
      uint8_t frame_only_constraint_flag;
  } PTLCommon;
  
  typedef struct PTL {
      PTLCommon general_ptl;
      PTLCommon sub_layer_ptl[MAX_SUB_LAYERS];
  
      uint8_t sub_layer_profile_present_flag[MAX_SUB_LAYERS];
      uint8_t sub_layer_level_present_flag[MAX_SUB_LAYERS];
  } PTL;
  
  typedef struct HEVCVPS {
      uint8_t vps_temporal_id_nesting_flag;
      int vps_max_layers;
      int vps_max_sub_layers; ///< vps_max_temporal_layers_minus1 + 1
  
      PTL ptl;
      int vps_sub_layer_ordering_info_present_flag;
      unsigned int vps_max_dec_pic_buffering[MAX_SUB_LAYERS];
      unsigned int vps_num_reorder_pics[MAX_SUB_LAYERS];
      unsigned int vps_max_latency_increase[MAX_SUB_LAYERS];
      int vps_max_layer_id;
      int vps_num_layer_sets; ///< vps_num_layer_sets_minus1 + 1
      uint8_t vps_timing_info_present_flag;
      uint32_t vps_num_units_in_tick;
      uint32_t vps_time_scale;
      uint8_t vps_poc_proportional_to_timing_flag;
      int vps_num_ticks_poc_diff_one; ///< vps_num_ticks_poc_diff_one_minus1 + 1
      int vps_num_hrd_parameters;
  } HEVCVPS;
  
  typedef struct ScalingList {
      /* This is a little wasteful, since sizeID 0 only needs 8 coeffs,
       * and size ID 3 only has 2 arrays, not 6. */
      uint8_t sl[4][6][64];
      uint8_t sl_dc[2][6];
  } ScalingList;
  
  typedef struct HEVCSPS {
      unsigned vps_id;
      int chroma_format_idc;
      uint8_t separate_colour_plane_flag;
  
      ///< output (i.e. cropped) values
      int output_width, output_height;
      HEVCWindow output_window;
  
      HEVCWindow pic_conf_win;
  
      int bit_depth;
      int pixel_shift;
      enum AVPixelFormat pix_fmt;
  
      unsigned int log2_max_poc_lsb;
      int pcm_enabled_flag;
  
      int max_sub_layers;
      struct {
          int max_dec_pic_buffering;
          int num_reorder_pics;
          int max_latency_increase;
      } temporal_layer[MAX_SUB_LAYERS];
  
      VUI vui;
      PTL ptl;
  
      uint8_t scaling_list_enable_flag;
      ScalingList scaling_list;
  
      unsigned int nb_st_rps;
      ShortTermRPS st_rps[MAX_SHORT_TERM_RPS_COUNT];
  
      uint8_t amp_enabled_flag;
      uint8_t sao_enabled;
  
      uint8_t long_term_ref_pics_present_flag;
      uint16_t lt_ref_pic_poc_lsb_sps[32];
      uint8_t used_by_curr_pic_lt_sps_flag[32];
      uint8_t num_long_term_ref_pics_sps;
  
      struct {
          uint8_t bit_depth;
          uint8_t bit_depth_chroma;
          unsigned int log2_min_pcm_cb_size;
          unsigned int log2_max_pcm_cb_size;
          uint8_t loop_filter_disable_flag;
      } pcm;
      uint8_t sps_temporal_mvp_enabled_flag;
      uint8_t sps_strong_intra_smoothing_enable_flag;
  
      unsigned int log2_min_cb_size;
      unsigned int log2_diff_max_min_coding_block_size;
      unsigned int log2_min_tb_size;
      unsigned int log2_max_trafo_size;
      unsigned int log2_ctb_size;
      unsigned int log2_min_pu_size;
  
      int max_transform_hierarchy_depth_inter;
      int max_transform_hierarchy_depth_intra;
  
      int transform_skip_rotation_enabled_flag;
      int transform_skip_context_enabled_flag;
      int implicit_rdpcm_enabled_flag;
      int explicit_rdpcm_enabled_flag;
      int intra_smoothing_disabled_flag;
      int persistent_rice_adaptation_enabled_flag;
  
      ///< coded frame dimension in various units
      int width;
      int height;
      int ctb_width;
      int ctb_height;
      int ctb_size;
      int min_cb_width;
      int min_cb_height;
      int min_tb_width;
      int min_tb_height;
      int min_pu_width;
      int min_pu_height;
      int tb_mask;
  
      int hshift[3];
      int vshift[3];
  
      int qp_bd_offset;
  } HEVCSPS;
  
  typedef struct HEVCPPS {
      unsigned int sps_id; ///< seq_parameter_set_id
  
      uint8_t sign_data_hiding_flag;
  
      uint8_t cabac_init_present_flag;
  
      int num_ref_idx_l0_default_active; ///< num_ref_idx_l0_default_active_minus1 + 1
      int num_ref_idx_l1_default_active; ///< num_ref_idx_l1_default_active_minus1 + 1
      int pic_init_qp_minus26;
  
      uint8_t constrained_intra_pred_flag;
      uint8_t transform_skip_enabled_flag;
  
      uint8_t cu_qp_delta_enabled_flag;
      int diff_cu_qp_delta_depth;
  
      int cb_qp_offset;
      int cr_qp_offset;
      uint8_t pic_slice_level_chroma_qp_offsets_present_flag;
      uint8_t weighted_pred_flag;
      uint8_t weighted_bipred_flag;
      uint8_t output_flag_present_flag;
      uint8_t transquant_bypass_enable_flag;
  
      uint8_t dependent_slice_segments_enabled_flag;
      uint8_t tiles_enabled_flag;
      uint8_t entropy_coding_sync_enabled_flag;
  
      int num_tile_columns;   ///< num_tile_columns_minus1 + 1
      int num_tile_rows;      ///< num_tile_rows_minus1 + 1
      uint8_t uniform_spacing_flag;
      uint8_t loop_filter_across_tiles_enabled_flag;
  
      uint8_t seq_loop_filter_across_slices_enabled_flag;
  
      uint8_t deblocking_filter_control_present_flag;
      uint8_t deblocking_filter_override_enabled_flag;
      uint8_t disable_dbf;
      int beta_offset;    ///< beta_offset_div2 * 2
      int tc_offset;      ///< tc_offset_div2 * 2
  
      uint8_t scaling_list_data_present_flag;
      ScalingList scaling_list;
  
      uint8_t lists_modification_present_flag;
      int log2_parallel_merge_level; ///< log2_parallel_merge_level_minus2 + 2
      int num_extra_slice_header_bits;
      uint8_t slice_header_extension_present_flag;
      uint8_t log2_max_transform_skip_block_size;
      uint8_t cross_component_prediction_enabled_flag;
      uint8_t chroma_qp_offset_list_enabled_flag;
      uint8_t diff_cu_chroma_qp_offset_depth;
      uint8_t chroma_qp_offset_list_len_minus1;
      int8_t  cb_qp_offset_list[5];
      int8_t  cr_qp_offset_list[5];
      uint8_t log2_sao_offset_scale_luma;
      uint8_t log2_sao_offset_scale_chroma;
  
      // Inferred parameters
      unsigned int *column_width;  ///< ColumnWidth
      unsigned int *row_height;    ///< RowHeight
      unsigned int *col_bd;        ///< ColBd
      unsigned int *row_bd;        ///< RowBd
      int *col_idxX;
  
      int *ctb_addr_rs_to_ts; ///< CtbAddrRSToTS
      int *ctb_addr_ts_to_rs; ///< CtbAddrTSToRS
      int *tile_id;           ///< TileId
      int *tile_pos_rs;       ///< TilePosRS
      int *min_tb_addr_zs;    ///< MinTbAddrZS
      int *min_tb_addr_zs_tab;///< MinTbAddrZS
  } HEVCPPS;
  
  typedef struct HEVCParamSets {
      AVBufferRef *vps_list[MAX_VPS_COUNT];
      AVBufferRef *sps_list[MAX_SPS_COUNT];
      AVBufferRef *pps_list[MAX_PPS_COUNT];
  
      /* currently active parameter sets */
      const HEVCVPS *vps;
      const HEVCSPS *sps;
      const HEVCPPS *pps;
  } HEVCParamSets;
  
  typedef struct SliceHeader {
      unsigned int pps_id;
  
      ///< address (in raster order) of the first block in the current slice segment
      unsigned int   slice_segment_addr;
      ///< address (in raster order) of the first block in the current slice
      unsigned int   slice_addr;
  
      enum SliceType slice_type;
  
      int pic_order_cnt_lsb;
  
      uint8_t first_slice_in_pic_flag;
      uint8_t dependent_slice_segment_flag;
      uint8_t pic_output_flag;
      uint8_t colour_plane_id;
  
      ///< RPS coded in the slice header itself is stored here
      int short_term_ref_pic_set_sps_flag;
      int short_term_ref_pic_set_size;
      ShortTermRPS slice_rps;
      const ShortTermRPS *short_term_rps;
      int long_term_ref_pic_set_size;
      LongTermRPS long_term_rps;
      unsigned int list_entry_lx[2][32];
  
      uint8_t rpl_modification_flag[2];
      uint8_t no_output_of_prior_pics_flag;
      uint8_t slice_temporal_mvp_enabled_flag;
  
      unsigned int nb_refs[2];
  
      uint8_t slice_sample_adaptive_offset_flag[3];
      uint8_t mvd_l1_zero_flag;
  
      uint8_t cabac_init_flag;
      uint8_t disable_deblocking_filter_flag; ///< slice_header_disable_deblocking_filter_flag
      uint8_t slice_loop_filter_across_slices_enabled_flag;
      uint8_t collocated_list;
  
      unsigned int collocated_ref_idx;
  
      int slice_qp_delta;
      int slice_cb_qp_offset;
      int slice_cr_qp_offset;
  
      uint8_t cu_chroma_qp_offset_enabled_flag;
  
      int beta_offset;    ///< beta_offset_div2 * 2
      int tc_offset;      ///< tc_offset_div2 * 2
  
      unsigned int max_num_merge_cand; ///< 5 - 5_minus_max_num_merge_cand
  
      int *entry_point_offset;
      int * offset;
      int * size;
      int num_entry_point_offsets;
  
      int8_t slice_qp;
  
      uint8_t luma_log2_weight_denom;
      int16_t chroma_log2_weight_denom;
  
      int16_t luma_weight_l0[16];
      int16_t chroma_weight_l0[16][2];
      int16_t chroma_weight_l1[16][2];
      int16_t luma_weight_l1[16];
  
      int16_t luma_offset_l0[16];
      int16_t chroma_offset_l0[16][2];
  
      int16_t luma_offset_l1[16];
      int16_t chroma_offset_l1[16][2];
  
      int slice_ctb_addr_rs;
  } SliceHeader;
  
  typedef struct CodingUnit {
      int x;
      int y;
  
      enum PredMode pred_mode;    ///< PredMode
      enum PartMode part_mode;    ///< PartMode
  
      // Inferred parameters
      uint8_t intra_split_flag;   ///< IntraSplitFlag
      uint8_t max_trafo_depth;    ///< MaxTrafoDepth
      uint8_t cu_transquant_bypass_flag;
  } CodingUnit;
  
  typedef struct Mv {
      int16_t x;  ///< horizontal component of motion vector
      int16_t y;  ///< vertical component of motion vector
  } Mv;
  
  typedef struct MvField {
      DECLARE_ALIGNED(4, Mv, mv)[2];
      int8_t ref_idx[2];
      int8_t pred_flag;
  } MvField;
  
  typedef struct NeighbourAvailable {
      int cand_bottom_left;
      int cand_left;
      int cand_up;
      int cand_up_left;
      int cand_up_right;
      int cand_up_right_sap;
  } NeighbourAvailable;
  
  typedef struct PredictionUnit {
      int mpm_idx;
      int rem_intra_luma_pred_mode;
      uint8_t intra_pred_mode[4];
      Mv mvd;
      uint8_t merge_flag;
      uint8_t intra_pred_mode_c[4];
      uint8_t chroma_mode_c[4];
  } PredictionUnit;
  
  typedef struct TransformUnit {
      int cu_qp_delta;
  
      int res_scale_val;
  
      // Inferred parameters;
      int intra_pred_mode;
      int intra_pred_mode_c;
      int chroma_mode_c;
      uint8_t is_cu_qp_delta_coded;
      uint8_t is_cu_chroma_qp_offset_coded;
      int8_t  cu_qp_offset_cb;
      int8_t  cu_qp_offset_cr;
      uint8_t cross_pf;
  } TransformUnit;
  
  typedef struct DBParams {
      int beta_offset;
      int tc_offset;
  } DBParams;
  
  #define HEVC_FRAME_FLAG_OUTPUT    (1 << 0)
  #define HEVC_FRAME_FLAG_SHORT_REF (1 << 1)
  #define HEVC_FRAME_FLAG_LONG_REF  (1 << 2)
  #define HEVC_FRAME_FLAG_BUMPING   (1 << 3)
  
  typedef struct HEVCFrame {
      AVFrame *frame;
      ThreadFrame tf;
      MvField *tab_mvf;
      RefPicList *refPicList;
      RefPicListTab **rpl_tab;
      int ctb_count;
      int poc;
      struct HEVCFrame *collocated_ref;
  
      HEVCWindow window;
  
      AVBufferRef *tab_mvf_buf;
      AVBufferRef *rpl_tab_buf;
      AVBufferRef *rpl_buf;
  
      AVBufferRef *hwaccel_priv_buf;
      void *hwaccel_picture_private;
  
      /**
       * A sequence counter, so that old frames are output first
       * after a POC reset
       */
      uint16_t sequence;
  
      /**
       * A combination of HEVC_FRAME_FLAG_*
       */
      uint8_t flags;
  } HEVCFrame;
  
  typedef struct HEVCNAL {
      uint8_t *rbsp_buffer;
      int rbsp_buffer_size;
  
      int size;
      const uint8_t *data;
  
      int raw_size;
      const uint8_t *raw_data;
  
      GetBitContext gb;
  
      enum NALUnitType type;
      int temporal_id;
  
      int skipped_bytes;
      int skipped_bytes_pos_size;
      int *skipped_bytes_pos;
  } HEVCNAL;
  
  /* an input packet split into unescaped NAL units */
  typedef struct HEVCPacket {
      HEVCNAL *nals;
      int nb_nals;
      int nals_allocated;
  } HEVCPacket;
  
  typedef struct HEVCLocalContext {
      uint8_t cabac_state[HEVC_CONTEXTS];
  
      uint8_t stat_coeff[4];
  
      uint8_t first_qp_group;
  
      GetBitContext gb;
      CABACContext cc;
  
      int8_t qp_y;
      int8_t curr_qp_y;
  
      int qPy_pred;
  
      TransformUnit tu;
  
      uint8_t ctb_left_flag;
      uint8_t ctb_up_flag;
      uint8_t ctb_up_right_flag;
      uint8_t ctb_up_left_flag;
      int     end_of_tiles_x;
      int     end_of_tiles_y;
      /* +7 is for subpixel interpolation, *2 for high bit depths */
      DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer)[(MAX_PB_SIZE + 7) * EDGE_EMU_BUFFER_STRIDE * 2];
      /* The extended size between the new edge emu buffer is abused by SAO */
      DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer2)[(MAX_PB_SIZE + 7) * EDGE_EMU_BUFFER_STRIDE * 2];
      DECLARE_ALIGNED(32, int16_t, tmp [MAX_PB_SIZE * MAX_PB_SIZE]);
  
      int ct_depth;
      CodingUnit cu;
      PredictionUnit pu;
      NeighbourAvailable na;
  
  #define BOUNDARY_LEFT_SLICE     (1 << 0)
  #define BOUNDARY_LEFT_TILE      (1 << 1)
  #define BOUNDARY_UPPER_SLICE    (1 << 2)
  #define BOUNDARY_UPPER_TILE     (1 << 3)
      /* properties of the boundary of the current CTB for the purposes
       * of the deblocking filter */
      int boundary_flags;
  } HEVCLocalContext;
  
  typedef struct HEVCContext {
      const AVClass *c;  // needed by private avoptions
      AVCodecContext *avctx;
  
      struct HEVCContext  *sList[MAX_NB_THREADS];
  
      HEVCLocalContext    *HEVClcList[MAX_NB_THREADS];
      HEVCLocalContext    *HEVClc;
  
      uint8_t             threads_type;
      uint8_t             threads_number;
  
      int                 width;
      int                 height;
  
      uint8_t *cabac_state;
  
      /** 1 if the independent slice segment header was successfully parsed */
      uint8_t slice_initialized;
  
      AVFrame *frame;
      AVFrame *output_frame;
      uint8_t *sao_pixel_buffer_h[3];
      uint8_t *sao_pixel_buffer_v[3];
  
      HEVCParamSets ps;
  
      AVBufferPool *tab_mvf_pool;
      AVBufferPool *rpl_tab_pool;
  
      ///< candidate references for the current frame
      RefPicList rps[5];
  
      SliceHeader sh;
      SAOParams *sao;
      DBParams *deblock;
      enum NALUnitType nal_unit_type;
      int temporal_id;  ///< temporal_id_plus1 - 1
      HEVCFrame *ref;
      HEVCFrame DPB[32];
      int poc;
      int pocTid0;
      int slice_idx; ///< number of the slice being currently decoded
      int eos;       ///< current packet contains an EOS/EOB NAL
      int last_eos;  ///< last packet contains an EOS/EOB NAL
      int max_ra;
      int bs_width;
      int bs_height;
  
      int is_decoded;
      int no_rasl_output_flag;
  
      HEVCPredContext hpc;
      HEVCDSPContext hevcdsp;
      VideoDSPContext vdsp;
      BswapDSPContext bdsp;
      int8_t *qp_y_tab;
      uint8_t *horizontal_bs;
      uint8_t *vertical_bs;
  
      int32_t *tab_slice_address;
  
      //  CU
      uint8_t *skip_flag;
      uint8_t *tab_ct_depth;
      // PU
      uint8_t *tab_ipm;
  
      uint8_t *cbf_luma; // cbf_luma of colocated TU
      uint8_t *is_pcm;
  
      // CTB-level flags affecting loop filter operation
      uint8_t *filter_slice_edges;
  
      /** used on BE to byteswap the lines for checksumming */
      uint8_t *checksum_buf;
      int      checksum_buf_size;
  
      /**
       * Sequence counters for decoded and output frames, so that old
       * frames are output first after a POC reset
       */
      uint16_t seq_decode;
      uint16_t seq_output;
  
      int enable_parallel_tiles;
      int wpp_err;
  
      const uint8_t *data;
  
      HEVCPacket pkt;
      // type of the first VCL NAL of the current frame
      enum NALUnitType first_nal_type;
  
      // for checking the frame checksums
      struct AVMD5 *md5_ctx;
      uint8_t       md5[3][16];
      uint8_t is_md5;
  
      uint8_t context_initialized;
      uint8_t is_nalff;       ///< this flag is != 0 if bitstream is encapsulated
                              ///< as a format defined in 14496-15
      int apply_defdispwin;
  
      int active_seq_parameter_set_id;
  
      int nal_length_size;    ///< Number of bytes used for nal length (1, 2 or 4)
      int nuh_layer_id;
  
      /** frame packing arrangement variables */
      int sei_frame_packing_present;
      int frame_packing_arrangement_type;
      int content_interpretation_type;
      int quincunx_subsampling;
  
      /** display orientation */
      int sei_display_orientation_present;
      int sei_anticlockwise_rotation;
      int sei_hflip, sei_vflip;
  
      int picture_struct;
  } HEVCContext;
  
  int ff_hevc_decode_short_term_rps(GetBitContext *gb, AVCodecContext *avctx,
                                    ShortTermRPS *rps, const HEVCSPS *sps, int is_slice_header);
  
  /**
   * Parse the SPS from the bitstream into the provided HEVCSPS struct.
   *
   * @param sps_id the SPS id will be written here
   * @param apply_defdispwin if set 1, the default display window from the VUI
   *                         will be applied to the video dimensions
   * @param vps_list if non-NULL, this function will validate that the SPS refers
   *                 to an existing VPS
   */
  int ff_hevc_parse_sps(HEVCSPS *sps, GetBitContext *gb, unsigned int *sps_id,
                        int apply_defdispwin, AVBufferRef **vps_list, AVCodecContext *avctx);
  
  int ff_hevc_decode_nal_vps(GetBitContext *gb, AVCodecContext *avctx,
                             HEVCParamSets *ps);
  int ff_hevc_decode_nal_sps(GetBitContext *gb, AVCodecContext *avctx,
                             HEVCParamSets *ps, int apply_defdispwin);
  int ff_hevc_decode_nal_pps(GetBitContext *gb, AVCodecContext *avctx,
                             HEVCParamSets *ps);
  int ff_hevc_decode_nal_sei(HEVCContext *s);
  
  /**
   * Mark all frames in DPB as unused for reference.
   */
  void ff_hevc_clear_refs(HEVCContext *s);
  
  /**
   * Drop all frames currently in DPB.
   */
  void ff_hevc_flush_dpb(HEVCContext *s);
  
  /**
   * Compute POC of the current frame and return it.
   */
  int ff_hevc_compute_poc(HEVCContext *s, int poc_lsb);
  
  RefPicList *ff_hevc_get_ref_list(HEVCContext *s, HEVCFrame *frame,
                                   int x0, int y0);
  
  /**
   * Construct the reference picture sets for the current frame.
   */
  int ff_hevc_frame_rps(HEVCContext *s);
  
  /**
   * Construct the reference picture list(s) for the current slice.
   */
  int ff_hevc_slice_rpl(HEVCContext *s);
  
  void ff_hevc_save_states(HEVCContext *s, int ctb_addr_ts);
  void ff_hevc_cabac_init(HEVCContext *s, int ctb_addr_ts);
  int ff_hevc_sao_merge_flag_decode(HEVCContext *s);
  int ff_hevc_sao_type_idx_decode(HEVCContext *s);
  int ff_hevc_sao_band_position_decode(HEVCContext *s);
  int ff_hevc_sao_offset_abs_decode(HEVCContext *s);
  int ff_hevc_sao_offset_sign_decode(HEVCContext *s);
  int ff_hevc_sao_eo_class_decode(HEVCContext *s);
  int ff_hevc_end_of_slice_flag_decode(HEVCContext *s);
  int ff_hevc_cu_transquant_bypass_flag_decode(HEVCContext *s);
  int ff_hevc_skip_flag_decode(HEVCContext *s, int x0, int y0,
                               int x_cb, int y_cb);
  int ff_hevc_pred_mode_decode(HEVCContext *s);
  int ff_hevc_split_coding_unit_flag_decode(HEVCContext *s, int ct_depth,
                                            int x0, int y0);
  int ff_hevc_part_mode_decode(HEVCContext *s, int log2_cb_size);
  int ff_hevc_pcm_flag_decode(HEVCContext *s);
  int ff_hevc_prev_intra_luma_pred_flag_decode(HEVCContext *s);
  int ff_hevc_mpm_idx_decode(HEVCContext *s);
  int ff_hevc_rem_intra_luma_pred_mode_decode(HEVCContext *s);
  int ff_hevc_intra_chroma_pred_mode_decode(HEVCContext *s);
  int ff_hevc_merge_idx_decode(HEVCContext *s);
  int ff_hevc_merge_flag_decode(HEVCContext *s);
  int ff_hevc_inter_pred_idc_decode(HEVCContext *s, int nPbW, int nPbH);
  int ff_hevc_ref_idx_lx_decode(HEVCContext *s, int num_ref_idx_lx);
  int ff_hevc_mvp_lx_flag_decode(HEVCContext *s);
  int ff_hevc_no_residual_syntax_flag_decode(HEVCContext *s);
  int ff_hevc_split_transform_flag_decode(HEVCContext *s, int log2_trafo_size);
  int ff_hevc_cbf_cb_cr_decode(HEVCContext *s, int trafo_depth);
  int ff_hevc_cbf_luma_decode(HEVCContext *s, int trafo_depth);
  int ff_hevc_log2_res_scale_abs(HEVCContext *s, int idx);
  int ff_hevc_res_scale_sign_flag(HEVCContext *s, int idx);
  
  /**
   * Get the number of candidate references for the current frame.
   */
  int ff_hevc_frame_nb_refs(HEVCContext *s);
  
  int ff_hevc_set_new_ref(HEVCContext *s, AVFrame **frame, int poc);
  
  /**
   * Find next frame in output order and put a reference to it in frame.
   * @return 1 if a frame was output, 0 otherwise
   */
  int ff_hevc_output_frame(HEVCContext *s, AVFrame *frame, int flush);
  
  void ff_hevc_bump_frame(HEVCContext *s);
  
  void ff_hevc_unref_frame(HEVCContext *s, HEVCFrame *frame, int flags);
  
  void ff_hevc_set_neighbour_available(HEVCContext *s, int x0, int y0,
                                       int nPbW, int nPbH);
  void ff_hevc_luma_mv_merge_mode(HEVCContext *s, int x0, int y0,
                                  int nPbW, int nPbH, int log2_cb_size,
                                  int part_idx, int merge_idx, MvField *mv);
  void ff_hevc_luma_mv_mvp_mode(HEVCContext *s, int x0, int y0,
                                int nPbW, int nPbH, int log2_cb_size,
                                int part_idx, int merge_idx,
                                MvField *mv, int mvp_lx_flag, int LX);
  void ff_hevc_set_qPy(HEVCContext *s, int xBase, int yBase,
                       int log2_cb_size);
  void ff_hevc_deblocking_boundary_strengths(HEVCContext *s, int x0, int y0,
                                             int log2_trafo_size);
  int ff_hevc_cu_qp_delta_sign_flag(HEVCContext *s);
  int ff_hevc_cu_qp_delta_abs(HEVCContext *s);
  int ff_hevc_cu_chroma_qp_offset_flag(HEVCContext *s);
  int ff_hevc_cu_chroma_qp_offset_idx(HEVCContext *s);
  void ff_hevc_hls_filter(HEVCContext *s, int x, int y, int ctb_size);
  void ff_hevc_hls_filters(HEVCContext *s, int x_ctb, int y_ctb, int ctb_size);
  void ff_hevc_hls_residual_coding(HEVCContext *s, int x0, int y0,
                                   int log2_trafo_size, enum ScanType scan_idx,
                                   int c_idx);
  
  void ff_hevc_hls_mvd_coding(HEVCContext *s, int x0, int y0, int log2_cb_size);
  
  
  /**
   * Extract the raw (unescaped) HEVC bitstream.
   */
  int ff_hevc_extract_rbsp(HEVCContext *s, const uint8_t *src, int length,
                           HEVCNAL *nal);
  
  /**
   * Split an input packet into NAL units.
   */
  int ff_hevc_split_packet(HEVCContext *s, HEVCPacket *pkt, const uint8_t *buf, int length,
                           AVCodecContext *avctx, int is_nalff, int nal_length_size);
  
  int ff_hevc_encode_nal_vps(HEVCVPS *vps, unsigned int id,
                             uint8_t *buf, int buf_size);
  
  extern const uint8_t ff_hevc_qpel_extra_before[4];
  extern const uint8_t ff_hevc_qpel_extra_after[4];
  extern const uint8_t ff_hevc_qpel_extra[4];
  
  extern const uint8_t ff_hevc_diag_scan4x4_x[16];
  extern const uint8_t ff_hevc_diag_scan4x4_y[16];
  extern const uint8_t ff_hevc_diag_scan8x8_x[64];
  extern const uint8_t ff_hevc_diag_scan8x8_y[64];
  
  #endif /* AVCODEC_HEVC_H */
  