1 // Copyright 2010 Google Inc. All Rights Reserved. 2 // 3 // This code is licensed under the same terms as WebM: 4 // Software License Agreement: http://www.webmproject.org/license/software/ 5 // Additional IP Rights Grant: http://www.webmproject.org/license/additional/ 6 // ----------------------------------------------------------------------------- 7 // 8 // VP8 decoder: internal header. 9 // 10 // Author: Skal (pascal.massimino (at) gmail.com) 11 12 #ifndef WEBP_DEC_VP8I_H_ 13 #define WEBP_DEC_VP8I_H_ 14 15 #include <string.h> // for memcpy() 16 #include "./vp8li.h" 17 #include "../utils/bit_reader.h" 18 #include "../utils/thread.h" 19 #include "../dsp/dsp.h" 20 21 #if defined(__cplusplus) || defined(c_plusplus) 22 extern "C" { 23 #endif 24 25 //------------------------------------------------------------------------------ 26 // Various defines and enums 27 28 // version numbers 29 #define DEC_MAJ_VERSION 0 30 #define DEC_MIN_VERSION 2 31 #define DEC_REV_VERSION 1 32 33 #define ONLY_KEYFRAME_CODE // to remove any code related to P-Frames 34 35 // intra prediction modes 36 enum { B_DC_PRED = 0, // 4x4 modes 37 B_TM_PRED, 38 B_VE_PRED, 39 B_HE_PRED, 40 B_RD_PRED, 41 B_VR_PRED, 42 B_LD_PRED, 43 B_VL_PRED, 44 B_HD_PRED, 45 B_HU_PRED, 46 NUM_BMODES = B_HU_PRED + 1 - B_DC_PRED, // = 10 47 48 // Luma16 or UV modes 49 DC_PRED = B_DC_PRED, V_PRED = B_VE_PRED, 50 H_PRED = B_HE_PRED, TM_PRED = B_TM_PRED, 51 B_PRED = NUM_BMODES, // refined I4x4 mode 52 53 // special modes 54 B_DC_PRED_NOTOP = 4, 55 B_DC_PRED_NOLEFT = 5, 56 B_DC_PRED_NOTOPLEFT = 6, 57 NUM_B_DC_MODES = 7 }; 58 59 enum { MB_FEATURE_TREE_PROBS = 3, 60 NUM_MB_SEGMENTS = 4, 61 NUM_REF_LF_DELTAS = 4, 62 NUM_MODE_LF_DELTAS = 4, // I4x4, ZERO, *, SPLIT 63 MAX_NUM_PARTITIONS = 8, 64 // Probabilities 65 NUM_TYPES = 4, 66 NUM_BANDS = 8, 67 NUM_CTX = 3, 68 NUM_PROBAS = 11, 69 NUM_MV_PROBAS = 19 }; 70 71 // YUV-cache parameters. 72 // Constraints are: We need to store one 16x16 block of luma samples (y), 73 // and two 8x8 chroma blocks (u/v). These are better be 16-bytes aligned, 74 // in order to be SIMD-friendly. We also need to store the top, left and 75 // top-left samples (from previously decoded blocks), along with four 76 // extra top-right samples for luma (intra4x4 prediction only). 77 // One possible layout is, using 32 * (17 + 9) bytes: 78 // 79 // .+------ <- only 1 pixel high 80 // .|yyyyt. 81 // .|yyyyt. 82 // .|yyyyt. 83 // .|yyyy.. 84 // .+--.+-- <- only 1 pixel high 85 // .|uu.|vv 86 // .|uu.|vv 87 // 88 // Every character is a 4x4 block, with legend: 89 // '.' = unused 90 // 'y' = y-samples 'u' = u-samples 'v' = u-samples 91 // '|' = left sample, '-' = top sample, '+' = top-left sample 92 // 't' = extra top-right sample for 4x4 modes 93 // With this layout, BPS (=Bytes Per Scan-line) is one cacheline size. 94 #define BPS 32 // this is the common stride used by yuv[] 95 #define YUV_SIZE (BPS * 17 + BPS * 9) 96 #define Y_SIZE (BPS * 17) 97 #define Y_OFF (BPS * 1 + 8) 98 #define U_OFF (Y_OFF + BPS * 16 + BPS) 99 #define V_OFF (U_OFF + 16) 100 101 //------------------------------------------------------------------------------ 102 // Headers 103 104 typedef struct { 105 uint8_t key_frame_; 106 uint8_t profile_; 107 uint8_t show_; 108 uint32_t partition_length_; 109 } VP8FrameHeader; 110 111 typedef struct { 112 uint16_t width_; 113 uint16_t height_; 114 uint8_t xscale_; 115 uint8_t yscale_; 116 uint8_t colorspace_; // 0 = YCbCr 117 uint8_t clamp_type_; 118 } VP8PictureHeader; 119 120 // segment features 121 typedef struct { 122 int use_segment_; 123 int update_map_; // whether to update the segment map or not 124 int absolute_delta_; // absolute or delta values for quantizer and filter 125 int8_t quantizer_[NUM_MB_SEGMENTS]; // quantization changes 126 int8_t filter_strength_[NUM_MB_SEGMENTS]; // filter strength for segments 127 } VP8SegmentHeader; 128 129 // Struct collecting all frame-persistent probabilities. 130 typedef struct { 131 uint8_t segments_[MB_FEATURE_TREE_PROBS]; 132 // Type: 0:Intra16-AC 1:Intra16-DC 2:Chroma 3:Intra4 133 uint8_t coeffs_[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS]; 134 #ifndef ONLY_KEYFRAME_CODE 135 uint8_t ymode_[4], uvmode_[3]; 136 uint8_t mv_[2][NUM_MV_PROBAS]; 137 #endif 138 } VP8Proba; 139 140 // Filter parameters 141 typedef struct { 142 int simple_; // 0=complex, 1=simple 143 int level_; // [0..63] 144 int sharpness_; // [0..7] 145 int use_lf_delta_; 146 int ref_lf_delta_[NUM_REF_LF_DELTAS]; 147 int mode_lf_delta_[NUM_MODE_LF_DELTAS]; 148 } VP8FilterHeader; 149 150 //------------------------------------------------------------------------------ 151 // Informations about the macroblocks. 152 153 typedef struct { // filter specs 154 unsigned int f_level_:6; // filter strength: 0..63 155 unsigned int f_ilevel_:6; // inner limit: 1..63 156 unsigned int f_inner_:1; // do inner filtering? 157 } VP8FInfo; 158 159 typedef struct { // used for syntax-parsing 160 unsigned int nz_:24; // non-zero AC/DC coeffs (24bit) 161 unsigned int dc_nz_:1; // non-zero DC coeffs 162 unsigned int skip_:1; // block type 163 } VP8MB; 164 165 // Dequantization matrices 166 typedef int quant_t[2]; // [DC / AC]. Can be 'uint16_t[2]' too (~slower). 167 typedef struct { 168 quant_t y1_mat_, y2_mat_, uv_mat_; 169 } VP8QuantMatrix; 170 171 // Persistent information needed by the parallel processing 172 typedef struct { 173 int id_; // cache row to process (in [0..2]) 174 int mb_y_; // macroblock position of the row 175 int filter_row_; // true if row-filtering is needed 176 VP8FInfo* f_info_; // filter strengths 177 VP8Io io_; // copy of the VP8Io to pass to put() 178 } VP8ThreadContext; 179 180 //------------------------------------------------------------------------------ 181 // VP8Decoder: the main opaque structure handed over to user 182 183 struct VP8Decoder { 184 VP8StatusCode status_; 185 int ready_; // true if ready to decode a picture with VP8Decode() 186 const char* error_msg_; // set when status_ is not OK. 187 188 // Main data source 189 VP8BitReader br_; 190 191 // headers 192 VP8FrameHeader frm_hdr_; 193 VP8PictureHeader pic_hdr_; 194 VP8FilterHeader filter_hdr_; 195 VP8SegmentHeader segment_hdr_; 196 197 // Worker 198 WebPWorker worker_; 199 int use_threads_; // use multi-thread 200 int cache_id_; // current cache row 201 int num_caches_; // number of cached rows of 16 pixels (1, 2 or 3) 202 VP8ThreadContext thread_ctx_; // Thread context 203 204 // dimension, in macroblock units. 205 int mb_w_, mb_h_; 206 207 // Macroblock to process/filter, depending on cropping and filter_type. 208 int tl_mb_x_, tl_mb_y_; // top-left MB that must be in-loop filtered 209 int br_mb_x_, br_mb_y_; // last bottom-right MB that must be decoded 210 211 // number of partitions. 212 int num_parts_; 213 // per-partition boolean decoders. 214 VP8BitReader parts_[MAX_NUM_PARTITIONS]; 215 216 // buffer refresh flags 217 // bit 0: refresh Gold, bit 1: refresh Alt 218 // bit 2-3: copy to Gold, bit 4-5: copy to Alt 219 // bit 6: Gold sign bias, bit 7: Alt sign bias 220 // bit 8: refresh last frame 221 uint32_t buffer_flags_; 222 223 // dequantization (one set of DC/AC dequant factor per segment) 224 VP8QuantMatrix dqm_[NUM_MB_SEGMENTS]; 225 226 // probabilities 227 VP8Proba proba_; 228 int use_skip_proba_; 229 uint8_t skip_p_; 230 #ifndef ONLY_KEYFRAME_CODE 231 uint8_t intra_p_, last_p_, golden_p_; 232 VP8Proba proba_saved_; 233 int update_proba_; 234 #endif 235 236 // Boundary data cache and persistent buffers. 237 uint8_t* intra_t_; // top intra modes values: 4 * mb_w_ 238 uint8_t intra_l_[4]; // left intra modes values 239 uint8_t* y_t_; // top luma samples: 16 * mb_w_ 240 uint8_t* u_t_, *v_t_; // top u/v samples: 8 * mb_w_ each 241 242 VP8MB* mb_info_; // contextual macroblock info (mb_w_ + 1) 243 VP8FInfo* f_info_; // filter strength info 244 uint8_t* yuv_b_; // main block for Y/U/V (size = YUV_SIZE) 245 int16_t* coeffs_; // 384 coeffs = (16+8+8) * 4*4 246 247 uint8_t* cache_y_; // macroblock row for storing unfiltered samples 248 uint8_t* cache_u_; 249 uint8_t* cache_v_; 250 int cache_y_stride_; 251 int cache_uv_stride_; 252 253 // main memory chunk for the above data. Persistent. 254 void* mem_; 255 size_t mem_size_; 256 257 // Per macroblock non-persistent infos. 258 int mb_x_, mb_y_; // current position, in macroblock units 259 uint8_t is_i4x4_; // true if intra4x4 260 uint8_t imodes_[16]; // one 16x16 mode (#0) or sixteen 4x4 modes 261 uint8_t uvmode_; // chroma prediction mode 262 uint8_t segment_; // block's segment 263 264 // bit-wise info about the content of each sub-4x4 blocks: there are 16 bits 265 // for luma (bits #0->#15), then 4 bits for chroma-u (#16->#19) and 4 bits for 266 // chroma-v (#20->#23), each corresponding to one 4x4 block in decoding order. 267 // If the bit is set, the 4x4 block contains some non-zero coefficients. 268 uint32_t non_zero_; 269 uint32_t non_zero_ac_; 270 271 // Filtering side-info 272 int filter_type_; // 0=off, 1=simple, 2=complex 273 int filter_row_; // per-row flag 274 VP8FInfo fstrengths_[NUM_MB_SEGMENTS][2]; // precalculated per-segment/type 275 276 // extensions 277 const uint8_t* alpha_data_; // compressed alpha data (if present) 278 size_t alpha_data_size_; 279 uint8_t* alpha_plane_; // output. Persistent, contains the whole data. 280 281 int layer_colorspace_; 282 const uint8_t* layer_data_; // compressed layer data (if present) 283 size_t layer_data_size_; 284 }; 285 286 //------------------------------------------------------------------------------ 287 // internal functions. Not public. 288 289 // in vp8.c 290 int VP8SetError(VP8Decoder* const dec, 291 VP8StatusCode error, const char* const msg); 292 293 // in tree.c 294 void VP8ResetProba(VP8Proba* const proba); 295 void VP8ParseProba(VP8BitReader* const br, VP8Decoder* const dec); 296 void VP8ParseIntraMode(VP8BitReader* const br, VP8Decoder* const dec); 297 298 // in quant.c 299 void VP8ParseQuant(VP8Decoder* const dec); 300 301 // in frame.c 302 int VP8InitFrame(VP8Decoder* const dec, VP8Io* io); 303 // Predict a block and add residual 304 void VP8ReconstructBlock(VP8Decoder* const dec); 305 // Call io->setup() and finish setting up scan parameters. 306 // After this call returns, one must always call VP8ExitCritical() with the 307 // same parameters. Both functions should be used in pair. Returns VP8_STATUS_OK 308 // if ok, otherwise sets and returns the error status on *dec. 309 VP8StatusCode VP8EnterCritical(VP8Decoder* const dec, VP8Io* const io); 310 // Must always be called in pair with VP8EnterCritical(). 311 // Returns false in case of error. 312 int VP8ExitCritical(VP8Decoder* const dec, VP8Io* const io); 313 // Process the last decoded row (filtering + output) 314 int VP8ProcessRow(VP8Decoder* const dec, VP8Io* const io); 315 // To be called at the start of a new scanline, to initialize predictors. 316 void VP8InitScanline(VP8Decoder* const dec); 317 // Decode one macroblock. Returns false if there is not enough data. 318 int VP8DecodeMB(VP8Decoder* const dec, VP8BitReader* const token_br); 319 320 // in alpha.c 321 const uint8_t* VP8DecompressAlphaRows(VP8Decoder* const dec, 322 int row, int num_rows); 323 324 // in layer.c 325 int VP8DecodeLayer(VP8Decoder* const dec); 326 327 //------------------------------------------------------------------------------ 328 329 #if defined(__cplusplus) || defined(c_plusplus) 330 } // extern "C" 331 #endif 332 333 #endif /* WEBP_DEC_VP8I_H_ */ 334
