view release on metacpan or  search on metacpan

webp-src/src/dec/vp8i.h  view on Meta::CPAN

  int mode_lf_delta_[NUM_MODE_LF_DELTAS];
} VP8FilterHeader;

//------------------------------------------------------------------------------
// Informations about the macroblocks.

typedef struct {  // filter specs
  unsigned int f_level_:6;      // filter strength: 0..63
  unsigned int f_ilevel_:6;     // inner limit: 1..63
  unsigned int f_inner_:1;      // do inner filtering?
} VP8FInfo;

typedef struct {  // used for syntax-parsing
  unsigned int nz_:24;       // non-zero AC/DC coeffs (24bit)
  unsigned int dc_nz_:1;     // non-zero DC coeffs
  unsigned int skip_:1;      // block type
} VP8MB;

// Dequantization matrices
typedef int quant_t[2];      // [DC / AC].  Can be 'uint16_t[2]' too (~slower).
typedef struct {
  quant_t y1_mat_, y2_mat_, uv_mat_;
} VP8QuantMatrix;

// Persistent information needed by the parallel processing
typedef struct {
  int id_;            // cache row to process (in [0..2])
  int mb_y_;          // macroblock position of the row
  int filter_row_;    // true if row-filtering is needed
  VP8FInfo* f_info_;  // filter strengths
  VP8Io io_;          // copy of the VP8Io to pass to put()
} VP8ThreadContext;

//------------------------------------------------------------------------------
// VP8Decoder: the main opaque structure handed over to user

struct VP8Decoder {
  VP8StatusCode status_;
  int ready_;     // true if ready to decode a picture with VP8Decode()
  const char* error_msg_;  // set when status_ is not OK.

  // Main data source
  VP8BitReader br_;

  // headers
  VP8FrameHeader   frm_hdr_;
  VP8PictureHeader pic_hdr_;
  VP8FilterHeader  filter_hdr_;
  VP8SegmentHeader segment_hdr_;

  // Worker
  WebPWorker worker_;
  int use_threads_;    // use multi-thread
  int cache_id_;       // current cache row
  int num_caches_;     // number of cached rows of 16 pixels (1, 2 or 3)
  VP8ThreadContext thread_ctx_;  // Thread context

  // dimension, in macroblock units.
  int mb_w_, mb_h_;

  // Macroblock to process/filter, depending on cropping and filter_type.
  int tl_mb_x_, tl_mb_y_;  // top-left MB that must be in-loop filtered
  int br_mb_x_, br_mb_y_;  // last bottom-right MB that must be decoded

  // number of partitions.
  int num_parts_;
  // per-partition boolean decoders.
  VP8BitReader parts_[MAX_NUM_PARTITIONS];

  // buffer refresh flags
  //   bit 0: refresh Gold, bit 1: refresh Alt
  //   bit 2-3: copy to Gold, bit 4-5: copy to Alt
  //   bit 6: Gold sign bias, bit 7: Alt sign bias
  //   bit 8: refresh last frame
  uint32_t buffer_flags_;

  // dequantization (one set of DC/AC dequant factor per segment)
  VP8QuantMatrix dqm_[NUM_MB_SEGMENTS];

  // probabilities
  VP8Proba proba_;
  int use_skip_proba_;
  uint8_t skip_p_;
#ifndef ONLY_KEYFRAME_CODE
  uint8_t intra_p_, last_p_, golden_p_;
  VP8Proba proba_saved_;
  int update_proba_;
#endif

  // Boundary data cache and persistent buffers.
  uint8_t* intra_t_;     // top intra modes values: 4 * mb_w_
  uint8_t  intra_l_[4];  // left intra modes values
  uint8_t* y_t_;         // top luma samples: 16 * mb_w_
  uint8_t* u_t_, *v_t_;  // top u/v samples: 8 * mb_w_ each

  VP8MB* mb_info_;       // contextual macroblock info (mb_w_ + 1)
  VP8FInfo* f_info_;     // filter strength info
  uint8_t* yuv_b_;       // main block for Y/U/V (size = YUV_SIZE)
  int16_t* coeffs_;      // 384 coeffs = (16+8+8) * 4*4

  uint8_t* cache_y_;     // macroblock row for storing unfiltered samples
  uint8_t* cache_u_;
  uint8_t* cache_v_;
  int cache_y_stride_;
  int cache_uv_stride_;

  // main memory chunk for the above data. Persistent.
  void* mem_;
  size_t mem_size_;

  // Per macroblock non-persistent infos.
  int mb_x_, mb_y_;       // current position, in macroblock units
  uint8_t is_i4x4_;       // true if intra4x4
  uint8_t imodes_[16];    // one 16x16 mode (#0) or sixteen 4x4 modes
  uint8_t uvmode_;        // chroma prediction mode
  uint8_t segment_;       // block's segment

  // bit-wise info about the content of each sub-4x4 blocks: there are 16 bits
  // for luma (bits #0->#15), then 4 bits for chroma-u (#16->#19) and 4 bits for
  // chroma-v (#20->#23), each corresponding to one 4x4 block in decoding order.
  // If the bit is set, the 4x4 block contains some non-zero coefficients.