/*

 * H.265 video codec.

 * Copyright (c) 2013-2014 struktur AG, Dirk Farin <farin@struktur.de>

 *

 * This file is part of libde265.

 *

 * libde265 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 3 of

 * the License, or (at your option) any later version.

 *

 * libde265 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 libde265.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef DE265_PPS_H

#define DE265_PPS_H

#include "libde265/bitstream.h"

#include "libde265/sps.h" // for scaling list only

#include <vector>

#include <memory>

constexpr int DE265_MAX_TILE_COLUMNS = 10;

constexpr int DE265_MAX_TILE_ROWS    = 10;

class decoder_context;

class pic_parameter_set;

class pps_range_extension

{

 public:

  pps_range_extension() { reset(); }

  void reset();

  bool read(bitreader*, decoder_context*, const pic_parameter_set*);

  void dump(int fd) const;

  uint8_t log2_max_transform_skip_block_size;

  bool    cross_component_prediction_enabled_flag;

  bool    chroma_qp_offset_list_enabled_flag;

  uint8_t diff_cu_chroma_qp_offset_depth;

  uint8_t chroma_qp_offset_list_len;

  int8_t  cb_qp_offset_list[6];

  int8_t  cr_qp_offset_list[6];

  uint8_t log2_sao_offset_scale_luma;

  uint8_t log2_sao_offset_scale_chroma;

};

// Picture-geometry-derived scan-order tables (HEVC Sec. 6.5). They depend only

// on the picture/tile geometry, are immutable after construction, and are shared

// read-only across pic_parameter_set instances (and across independent decoder

// contexts) through a small library-scope cache -- see pps.cc. Sharing avoids

// recomputing the (potentially large) MinTbAddrZS table once per decoder when

// many contexts decode images of the same geometry (e.g. libheif tile grids).

struct pps_scan_tables {

  std::vector<uint32_t> CtbAddrRStoTS; // #CTBs

  std::vector<uint32_t> CtbAddrTStoRS; // #CTBs

  std::vector<uint32_t> TileId;        // #CTBs  // index in tile-scan order

  std::vector<uint32_t> TileIdRS;      // #CTBs  // index in raster-scan order

  std::vector<uint32_t> MinTbAddrZS;   // #TBs   [x + y*PicWidthInTbsY]

};

// Library-scope scan-table cache lifecycle, tied to de265_init() / de265_free()

// so the cache is released when the library is de-initialized (no leak at exit).

void pps_scan_cache_init();

void pps_scan_cache_free();

class pic_parameter_set {

public:

  pic_parameter_set();

  ~pic_parameter_set();

  void reset() { set_defaults(); }

  bool read(bitreader*, decoder_context*);

  bool write(error_queue*, CABAC_encoder&,

             const seq_parameter_set* sps);

  bool is_tile_start_CTB(int ctbX,int ctbY) const;

  void dump(int fd) const;

  void set_defaults(enum PresetSet = Preset_Default);

  bool pps_read; // whether this pps has been read from bitstream

  std::shared_ptr<const seq_parameter_set> sps;

  uint8_t pic_parameter_set_id;

  uint8_t seq_parameter_set_id;

  bool dependent_slice_segments_enabled_flag;

  bool sign_data_hiding_flag;

  bool cabac_init_present_flag;

  uint8_t num_ref_idx_l0_default_active; // [1;16]

  uint8_t num_ref_idx_l1_default_active; // [1;16]

  int pic_init_qp;

  bool constrained_intra_pred_flag;

  bool transform_skip_enabled_flag;

  // --- QP ---

  bool cu_qp_delta_enabled_flag;

  uint8_t diff_cu_qp_delta_depth;   // [ 0 ; log2_diff_max_min_luma_coding_block_size ]

  int  pic_cb_qp_offset;

  int  pic_cr_qp_offset;

  bool pps_slice_chroma_qp_offsets_present_flag;

  bool weighted_pred_flag;

  bool weighted_bipred_flag;

  bool output_flag_present_flag;

  bool transquant_bypass_enable_flag;

  bool entropy_coding_sync_enabled_flag;

  // --- tiles ---

  bool tiles_enabled_flag;

  uint8_t num_tile_columns;  // [1;PicWidthInCtbsY] max DE265_MAX_TILE_COLUMNS

  uint8_t num_tile_rows;     // [1;PicHeightInCtbsY] max DE265_MAX_TILE_ROWS

  bool uniform_spacing_flag;

  // --- ---

  bool loop_filter_across_tiles_enabled_flag;

  bool pps_loop_filter_across_slices_enabled_flag;

  bool deblocking_filter_control_present_flag;

  bool deblocking_filter_override_enabled_flag;

  bool pic_disable_deblocking_filter_flag;

  int8_t beta_offset;  // [-12;12]

  int8_t tc_offset;    // [-12;12]

  bool pic_scaling_list_data_present_flag;

  scaling_list_data scaling_list; // contains valid data if sps->scaling_list_enabled_flag set

  bool lists_modification_present_flag;

  uint8_t log2_parallel_merge_level; // [2 ; log2(max CB size)]

  uint8_t num_extra_slice_header_bits;

  bool slice_segment_header_extension_present_flag;

  bool pps_extension_flag;

  bool pps_range_extension_flag;

  bool pps_multilayer_extension_flag;

  uint8_t pps_extension_6bits;

  pps_range_extension range_extension;

  // --- derived values ---

  int Log2MinCuQpDeltaSize;

  int Log2MinCuChromaQpOffsetSize;

  int Log2MaxTransformSkipSize;

  uint16_t colWidth [ DE265_MAX_TILE_COLUMNS ];

  uint16_t rowHeight[ DE265_MAX_TILE_ROWS ];

  uint16_t colBd    [ DE265_MAX_TILE_COLUMNS+1 ];

  uint16_t rowBd    [ DE265_MAX_TILE_ROWS+1 ];

  // Derived scan-order tables (Sec. 6.5), shared read-only via the library-scope

  // cache. Access as scan->CtbAddrRStoTS[...], scan->MinTbAddrZS[...], etc.

  std::shared_ptr<const pps_scan_tables> scan;

  void set_derived_values(const seq_parameter_set* sps);

};

#endif