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      1 // Copyright 2011 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 // WebP encoder: main entry point
      9 //
     10 // Author: Skal (pascal.massimino (at) gmail.com)
     11 
     12 #include <assert.h>
     13 #include <stdlib.h>
     14 #include <string.h>
     15 #include <math.h>
     16 
     17 #include "./vp8enci.h"
     18 #include "./vp8li.h"
     19 #include "../utils/utils.h"
     20 
     21 // #define PRINT_MEMORY_INFO
     22 
     23 #if defined(__cplusplus) || defined(c_plusplus)
     24 extern "C" {
     25 #endif
     26 
     27 #ifdef PRINT_MEMORY_INFO
     28 #include <stdio.h>
     29 #endif
     30 
     31 //------------------------------------------------------------------------------
     32 
     33 int WebPGetEncoderVersion(void) {
     34   return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
     35 }
     36 
     37 //------------------------------------------------------------------------------
     38 // WebPPicture
     39 //------------------------------------------------------------------------------
     40 
     41 static int DummyWriter(const uint8_t* data, size_t data_size,
     42                        const WebPPicture* const picture) {
     43   // The following are to prevent 'unused variable' error message.
     44   (void)data;
     45   (void)data_size;
     46   (void)picture;
     47   return 1;
     48 }
     49 
     50 int WebPPictureInitInternal(WebPPicture* picture, int version) {
     51   if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
     52     return 0;   // caller/system version mismatch!
     53   }
     54   if (picture != NULL) {
     55     memset(picture, 0, sizeof(*picture));
     56     picture->writer = DummyWriter;
     57     WebPEncodingSetError(picture, VP8_ENC_OK);
     58   }
     59   return 1;
     60 }
     61 
     62 //------------------------------------------------------------------------------
     63 // VP8Encoder
     64 //------------------------------------------------------------------------------
     65 
     66 static void ResetSegmentHeader(VP8Encoder* const enc) {
     67   VP8SegmentHeader* const hdr = &enc->segment_hdr_;
     68   hdr->num_segments_ = enc->config_->segments;
     69   hdr->update_map_  = (hdr->num_segments_ > 1);
     70   hdr->size_ = 0;
     71 }
     72 
     73 static void ResetFilterHeader(VP8Encoder* const enc) {
     74   VP8FilterHeader* const hdr = &enc->filter_hdr_;
     75   hdr->simple_ = 1;
     76   hdr->level_ = 0;
     77   hdr->sharpness_ = 0;
     78   hdr->i4x4_lf_delta_ = 0;
     79 }
     80 
     81 static void ResetBoundaryPredictions(VP8Encoder* const enc) {
     82   // init boundary values once for all
     83   // Note: actually, initializing the preds_[] is only needed for intra4.
     84   int i;
     85   uint8_t* const top = enc->preds_ - enc->preds_w_;
     86   uint8_t* const left = enc->preds_ - 1;
     87   for (i = -1; i < 4 * enc->mb_w_; ++i) {
     88     top[i] = B_DC_PRED;
     89   }
     90   for (i = 0; i < 4 * enc->mb_h_; ++i) {
     91     left[i * enc->preds_w_] = B_DC_PRED;
     92   }
     93   enc->nz_[-1] = 0;   // constant
     94 }
     95 
     96 // Mapping from config->method_ to coding tools used.
     97 //-------------------+---+---+---+---+---+---+---+
     98 //   Method          | 0 | 1 | 2 | 3 |(4)| 5 | 6 |
     99 //-------------------+---+---+---+---+---+---+---+
    100 // fast probe        | x |   |   | x |   |   |   |
    101 //-------------------+---+---+---+---+---+---+---+
    102 // dynamic proba     | ~ | x | x | x | x | x | x |
    103 //-------------------+---+---+---+---+---+---+---+
    104 // fast mode analysis|   |   |   |   | x | x | x |
    105 //-------------------+---+---+---+---+---+---+---+
    106 // basic rd-opt      |   |   |   | x | x | x | x |
    107 //-------------------+---+---+---+---+---+---+---+
    108 // disto-score i4/16 |   |   | x |   |   |   |   |
    109 //-------------------+---+---+---+---+---+---+---+
    110 // rd-opt i4/16      |   |   | ~ | x | x | x | x |
    111 //-------------------+---+---+---+---+---+---+---+
    112 // token buffer (opt)|   |   |   | x | x | x | x |
    113 //-------------------+---+---+---+---+---+---+---+
    114 // Trellis           |   |   |   |   |   | x |Ful|
    115 //-------------------+---+---+---+---+---+---+---+
    116 // full-SNS          |   |   |   |   | x | x | x |
    117 //-------------------+---+---+---+---+---+---+---+
    118 
    119 static void MapConfigToTools(VP8Encoder* const enc) {
    120   const WebPConfig* const config = enc->config_;
    121   const int method = config->method;
    122   const int limit = 100 - config->partition_limit;
    123   enc->method_ = method;
    124   enc->rd_opt_level_ = (method >= 6) ? RD_OPT_TRELLIS_ALL
    125                      : (method >= 5) ? RD_OPT_TRELLIS
    126                      : (method >= 3) ? RD_OPT_BASIC
    127                      : RD_OPT_NONE;
    128   enc->max_i4_header_bits_ =
    129       256 * 16 * 16 *                 // upper bound: up to 16bit per 4x4 block
    130       (limit * limit) / (100 * 100);  // ... modulated with a quadratic curve.
    131 
    132   enc->thread_level_ = config->thread_level;
    133 
    134   enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
    135   if (!config->low_memory) {
    136 #if !defined(DISABLE_TOKEN_BUFFER)
    137     enc->use_tokens_ = (method >= 3) && !enc->do_search_;
    138 #endif
    139     if (enc->use_tokens_) {
    140       enc->num_parts_ = 1;   // doesn't work with multi-partition
    141     }
    142   }
    143 }
    144 
    145 // Memory scaling with dimensions:
    146 //  memory (bytes) ~= 2.25 * w + 0.0625 * w * h
    147 //
    148 // Typical memory footprint (768x510 picture)
    149 // Memory used:
    150 //              encoder: 33919
    151 //          block cache: 2880
    152 //                 info: 3072
    153 //                preds: 24897
    154 //          top samples: 1623
    155 //             non-zero: 196
    156 //             lf-stats: 2048
    157 //                total: 68635
    158 // Transcient object sizes:
    159 //       VP8EncIterator: 352
    160 //         VP8ModeScore: 912
    161 //       VP8SegmentInfo: 532
    162 //             VP8Proba: 31032
    163 //              LFStats: 2048
    164 // Picture size (yuv): 589824
    165 
    166 static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
    167                                   WebPPicture* const picture) {
    168   const int use_filter =
    169       (config->filter_strength > 0) || (config->autofilter > 0);
    170   const int mb_w = (picture->width + 15) >> 4;
    171   const int mb_h = (picture->height + 15) >> 4;
    172   const int preds_w = 4 * mb_w + 1;
    173   const int preds_h = 4 * mb_h + 1;
    174   const size_t preds_size = preds_w * preds_h * sizeof(uint8_t);
    175   const int top_stride = mb_w * 16;
    176   const size_t nz_size = (mb_w + 1) * sizeof(uint32_t);
    177   const size_t cache_size = (3 * YUV_SIZE + PRED_SIZE) * sizeof(uint8_t);
    178   const size_t info_size = mb_w * mb_h * sizeof(VP8MBInfo);
    179   const size_t samples_size = (2 * top_stride +         // top-luma/u/v
    180                                16 + 16 + 16 + 8 + 1 +   // left y/u/v
    181                                2 * ALIGN_CST)           // align all
    182                                * sizeof(uint8_t);
    183   const size_t lf_stats_size =
    184       config->autofilter ? sizeof(LFStats) + ALIGN_CST : 0;
    185   VP8Encoder* enc;
    186   uint8_t* mem;
    187   const uint64_t size = (uint64_t)sizeof(VP8Encoder)   // main struct
    188                       + ALIGN_CST                      // cache alignment
    189                       + cache_size                     // working caches
    190                       + info_size                      // modes info
    191                       + preds_size                     // prediction modes
    192                       + samples_size                   // top/left samples
    193                       + nz_size                        // coeff context bits
    194                       + lf_stats_size;                 // autofilter stats
    195 
    196 #ifdef PRINT_MEMORY_INFO
    197   printf("===================================\n");
    198   printf("Memory used:\n"
    199          "             encoder: %ld\n"
    200          "         block cache: %ld\n"
    201          "                info: %ld\n"
    202          "               preds: %ld\n"
    203          "         top samples: %ld\n"
    204          "            non-zero: %ld\n"
    205          "            lf-stats: %ld\n"
    206          "               total: %ld\n",
    207          sizeof(VP8Encoder) + ALIGN_CST, cache_size, info_size,
    208          preds_size, samples_size, nz_size, lf_stats_size, size);
    209   printf("Transcient object sizes:\n"
    210          "      VP8EncIterator: %ld\n"
    211          "        VP8ModeScore: %ld\n"
    212          "      VP8SegmentInfo: %ld\n"
    213          "            VP8Proba: %ld\n"
    214          "             LFStats: %ld\n",
    215          sizeof(VP8EncIterator), sizeof(VP8ModeScore),
    216          sizeof(VP8SegmentInfo), sizeof(VP8Proba),
    217          sizeof(LFStats));
    218   printf("Picture size (yuv): %ld\n",
    219          mb_w * mb_h * 384 * sizeof(uint8_t));
    220   printf("===================================\n");
    221 #endif
    222   mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
    223   if (mem == NULL) {
    224     WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
    225     return NULL;
    226   }
    227   enc = (VP8Encoder*)mem;
    228   mem = (uint8_t*)DO_ALIGN(mem + sizeof(*enc));
    229   memset(enc, 0, sizeof(*enc));
    230   enc->num_parts_ = 1 << config->partitions;
    231   enc->mb_w_ = mb_w;
    232   enc->mb_h_ = mb_h;
    233   enc->preds_w_ = preds_w;
    234   enc->yuv_in_ = (uint8_t*)mem;
    235   mem += YUV_SIZE;
    236   enc->yuv_out_ = (uint8_t*)mem;
    237   mem += YUV_SIZE;
    238   enc->yuv_out2_ = (uint8_t*)mem;
    239   mem += YUV_SIZE;
    240   enc->yuv_p_ = (uint8_t*)mem;
    241   mem += PRED_SIZE;
    242   enc->mb_info_ = (VP8MBInfo*)mem;
    243   mem += info_size;
    244   enc->preds_ = ((uint8_t*)mem) + 1 + enc->preds_w_;
    245   mem += preds_w * preds_h * sizeof(uint8_t);
    246   enc->nz_ = 1 + (uint32_t*)mem;
    247   mem += nz_size;
    248   enc->lf_stats_ = lf_stats_size ? (LFStats*)DO_ALIGN(mem) : NULL;
    249   mem += lf_stats_size;
    250 
    251   // top samples (all 16-aligned)
    252   mem = (uint8_t*)DO_ALIGN(mem);
    253   enc->y_top_ = (uint8_t*)mem;
    254   enc->uv_top_ = enc->y_top_ + top_stride;
    255   mem += 2 * top_stride;
    256   mem = (uint8_t*)DO_ALIGN(mem + 1);
    257   enc->y_left_ = (uint8_t*)mem;
    258   mem += 16 + 16;
    259   enc->u_left_ = (uint8_t*)mem;
    260   mem += 16;
    261   enc->v_left_ = (uint8_t*)mem;
    262   mem += 8;
    263 
    264   enc->config_ = config;
    265   enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
    266   enc->pic_ = picture;
    267   enc->percent_ = 0;
    268 
    269   MapConfigToTools(enc);
    270   VP8EncDspInit();
    271   VP8DefaultProbas(enc);
    272   ResetSegmentHeader(enc);
    273   ResetFilterHeader(enc);
    274   ResetBoundaryPredictions(enc);
    275 
    276   VP8EncInitAlpha(enc);
    277 #ifdef WEBP_EXPERIMENTAL_FEATURES
    278   VP8EncInitLayer(enc);
    279 #endif
    280 
    281   VP8TBufferInit(&enc->tokens_);
    282   return enc;
    283 }
    284 
    285 static int DeleteVP8Encoder(VP8Encoder* enc) {
    286   int ok = 1;
    287   if (enc != NULL) {
    288     ok = VP8EncDeleteAlpha(enc);
    289 #ifdef WEBP_EXPERIMENTAL_FEATURES
    290     VP8EncDeleteLayer(enc);
    291 #endif
    292     VP8TBufferClear(&enc->tokens_);
    293     free(enc);
    294   }
    295   return ok;
    296 }
    297 
    298 //------------------------------------------------------------------------------
    299 
    300 static double GetPSNR(uint64_t err, uint64_t size) {
    301   return err ? 10. * log10(255. * 255. * size / err) : 99.;
    302 }
    303 
    304 static void FinalizePSNR(const VP8Encoder* const enc) {
    305   WebPAuxStats* stats = enc->pic_->stats;
    306   const uint64_t size = enc->sse_count_;
    307   const uint64_t* const sse = enc->sse_;
    308   stats->PSNR[0] = (float)GetPSNR(sse[0], size);
    309   stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
    310   stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
    311   stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
    312   stats->PSNR[4] = (float)GetPSNR(sse[3], size);
    313 }
    314 
    315 static void StoreStats(VP8Encoder* const enc) {
    316   WebPAuxStats* const stats = enc->pic_->stats;
    317   if (stats != NULL) {
    318     int i, s;
    319     for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
    320       stats->segment_level[i] = enc->dqm_[i].fstrength_;
    321       stats->segment_quant[i] = enc->dqm_[i].quant_;
    322       for (s = 0; s <= 2; ++s) {
    323         stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
    324       }
    325     }
    326     FinalizePSNR(enc);
    327     stats->coded_size = enc->coded_size_;
    328     for (i = 0; i < 3; ++i) {
    329       stats->block_count[i] = enc->block_count_[i];
    330     }
    331   }
    332   WebPReportProgress(enc->pic_, 100, &enc->percent_);  // done!
    333 }
    334 
    335 int WebPEncodingSetError(const WebPPicture* const pic,
    336                          WebPEncodingError error) {
    337   assert((int)error < VP8_ENC_ERROR_LAST);
    338   assert((int)error >= VP8_ENC_OK);
    339   ((WebPPicture*)pic)->error_code = error;
    340   return 0;
    341 }
    342 
    343 int WebPReportProgress(const WebPPicture* const pic,
    344                        int percent, int* const percent_store) {
    345   if (percent_store != NULL && percent != *percent_store) {
    346     *percent_store = percent;
    347     if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
    348       // user abort requested
    349       WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
    350       return 0;
    351     }
    352   }
    353   return 1;  // ok
    354 }
    355 //------------------------------------------------------------------------------
    356 
    357 int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
    358   int ok = 0;
    359 
    360   if (pic == NULL)
    361     return 0;
    362   WebPEncodingSetError(pic, VP8_ENC_OK);  // all ok so far
    363   if (config == NULL)  // bad params
    364     return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
    365   if (!WebPValidateConfig(config))
    366     return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
    367   if (pic->width <= 0 || pic->height <= 0)
    368     return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
    369   if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION)
    370     return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
    371 
    372   if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
    373 
    374   if (!config->lossless) {
    375     VP8Encoder* enc = NULL;
    376     if (pic->y == NULL || pic->u == NULL || pic->v == NULL) {
    377       if (pic->argb != NULL) {
    378         if (!WebPPictureARGBToYUVA(pic, WEBP_YUV420)) return 0;
    379       } else {
    380         return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
    381       }
    382     }
    383 
    384     enc = InitVP8Encoder(config, pic);
    385     if (enc == NULL) return 0;  // pic->error is already set.
    386     // Note: each of the tasks below account for 20% in the progress report.
    387     ok = VP8EncAnalyze(enc);
    388 
    389     // Analysis is done, proceed to actual coding.
    390     ok = ok && VP8EncStartAlpha(enc);   // possibly done in parallel
    391     if (!enc->use_tokens_) {
    392       ok = VP8EncLoop(enc);
    393     } else {
    394       ok = VP8EncTokenLoop(enc);
    395     }
    396     ok = ok && VP8EncFinishAlpha(enc);
    397 #ifdef WEBP_EXPERIMENTAL_FEATURES
    398     ok = ok && VP8EncFinishLayer(enc);
    399 #endif
    400 
    401     ok = ok && VP8EncWrite(enc);
    402     StoreStats(enc);
    403     if (!ok) {
    404       VP8EncFreeBitWriters(enc);
    405     }
    406     ok &= DeleteVP8Encoder(enc);  // must always be called, even if !ok
    407   } else {
    408     if (pic->argb == NULL)
    409       return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
    410 
    411     ok = VP8LEncodeImage(config, pic);  // Sets pic->error in case of problem.
    412   }
    413 
    414   return ok;
    415 }
    416 
    417 #if defined(__cplusplus) || defined(c_plusplus)
    418 }    // extern "C"
    419 #endif
    420