1 // Copyright 2011 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 // WebP encoder: main entry point
11 //
12 // Author: Skal (pascal.massimino@gmail.com)
13
14 #include <assert.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <math.h>
18
19 #include "./cost.h"
20 #include "./vp8enci.h"
21 #include "./vp8li.h"
22 #include "../utils/utils.h"
23
24 // #define PRINT_MEMORY_INFO
25
26 #ifdef PRINT_MEMORY_INFO
27 #include <stdio.h>
28 #endif
29
30 //------------------------------------------------------------------------------
31
WebPGetEncoderVersion(void)32 int WebPGetEncoderVersion(void) {
33 return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
34 }
35
36 //------------------------------------------------------------------------------
37 // VP8Encoder
38 //------------------------------------------------------------------------------
39
ResetSegmentHeader(VP8Encoder * const enc)40 static void ResetSegmentHeader(VP8Encoder* const enc) {
41 VP8EncSegmentHeader* const hdr = &enc->segment_hdr_;
42 hdr->num_segments_ = enc->config_->segments;
43 hdr->update_map_ = (hdr->num_segments_ > 1);
44 hdr->size_ = 0;
45 }
46
ResetFilterHeader(VP8Encoder * const enc)47 static void ResetFilterHeader(VP8Encoder* const enc) {
48 VP8EncFilterHeader* const hdr = &enc->filter_hdr_;
49 hdr->simple_ = 1;
50 hdr->level_ = 0;
51 hdr->sharpness_ = 0;
52 hdr->i4x4_lf_delta_ = 0;
53 }
54
ResetBoundaryPredictions(VP8Encoder * const enc)55 static void ResetBoundaryPredictions(VP8Encoder* const enc) {
56 // init boundary values once for all
57 // Note: actually, initializing the preds_[] is only needed for intra4.
58 int i;
59 uint8_t* const top = enc->preds_ - enc->preds_w_;
60 uint8_t* const left = enc->preds_ - 1;
61 for (i = -1; i < 4 * enc->mb_w_; ++i) {
62 top[i] = B_DC_PRED;
63 }
64 for (i = 0; i < 4 * enc->mb_h_; ++i) {
65 left[i * enc->preds_w_] = B_DC_PRED;
66 }
67 enc->nz_[-1] = 0; // constant
68 }
69
70 // Mapping from config->method_ to coding tools used.
71 //-------------------+---+---+---+---+---+---+---+
72 // Method | 0 | 1 | 2 | 3 |(4)| 5 | 6 |
73 //-------------------+---+---+---+---+---+---+---+
74 // fast probe | x | | | x | | | |
75 //-------------------+---+---+---+---+---+---+---+
76 // dynamic proba | ~ | x | x | x | x | x | x |
77 //-------------------+---+---+---+---+---+---+---+
78 // fast mode analysis| | | | | x | x | x |
79 //-------------------+---+---+---+---+---+---+---+
80 // basic rd-opt | | | | x | x | x | x |
81 //-------------------+---+---+---+---+---+---+---+
82 // disto-refine i4/16| x | x | x | | | | |
83 //-------------------+---+---+---+---+---+---+---+
84 // disto-refine uv | | x | x | | | | |
85 //-------------------+---+---+---+---+---+---+---+
86 // rd-opt i4/16 | | | ~ | x | x | x | x |
87 //-------------------+---+---+---+---+---+---+---+
88 // token buffer (opt)| | | | x | x | x | x |
89 //-------------------+---+---+---+---+---+---+---+
90 // Trellis | | | | | | x |Ful|
91 //-------------------+---+---+---+---+---+---+---+
92 // full-SNS | | | | | x | x | x |
93 //-------------------+---+---+---+---+---+---+---+
94
MapConfigToTools(VP8Encoder * const enc)95 static void MapConfigToTools(VP8Encoder* const enc) {
96 const WebPConfig* const config = enc->config_;
97 const int method = config->method;
98 const int limit = 100 - config->partition_limit;
99 enc->method_ = method;
100 enc->rd_opt_level_ = (method >= 6) ? RD_OPT_TRELLIS_ALL
101 : (method >= 5) ? RD_OPT_TRELLIS
102 : (method >= 3) ? RD_OPT_BASIC
103 : RD_OPT_NONE;
104 enc->max_i4_header_bits_ =
105 256 * 16 * 16 * // upper bound: up to 16bit per 4x4 block
106 (limit * limit) / (100 * 100); // ... modulated with a quadratic curve.
107
108 enc->thread_level_ = config->thread_level;
109
110 enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
111 if (!config->low_memory) {
112 #if !defined(DISABLE_TOKEN_BUFFER)
113 enc->use_tokens_ = (enc->rd_opt_level_ >= RD_OPT_BASIC); // need rd stats
114 #endif
115 if (enc->use_tokens_) {
116 enc->num_parts_ = 1; // doesn't work with multi-partition
117 }
118 }
119 }
120
121 // Memory scaling with dimensions:
122 // memory (bytes) ~= 2.25 * w + 0.0625 * w * h
123 //
124 // Typical memory footprint (614x440 picture)
125 // encoder: 22111
126 // info: 4368
127 // preds: 17741
128 // top samples: 1263
129 // non-zero: 175
130 // lf-stats: 0
131 // total: 45658
132 // Transient object sizes:
133 // VP8EncIterator: 3360
134 // VP8ModeScore: 872
135 // VP8SegmentInfo: 732
136 // VP8EncProba: 18352
137 // LFStats: 2048
138 // Picture size (yuv): 419328
139
InitVP8Encoder(const WebPConfig * const config,WebPPicture * const picture)140 static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
141 WebPPicture* const picture) {
142 VP8Encoder* enc;
143 const int use_filter =
144 (config->filter_strength > 0) || (config->autofilter > 0);
145 const int mb_w = (picture->width + 15) >> 4;
146 const int mb_h = (picture->height + 15) >> 4;
147 const int preds_w = 4 * mb_w + 1;
148 const int preds_h = 4 * mb_h + 1;
149 const size_t preds_size = preds_w * preds_h * sizeof(*enc->preds_);
150 const int top_stride = mb_w * 16;
151 const size_t nz_size = (mb_w + 1) * sizeof(*enc->nz_) + WEBP_ALIGN_CST;
152 const size_t info_size = mb_w * mb_h * sizeof(*enc->mb_info_);
153 const size_t samples_size =
154 2 * top_stride * sizeof(*enc->y_top_) // top-luma/u/v
155 + WEBP_ALIGN_CST; // align all
156 const size_t lf_stats_size =
157 config->autofilter ? sizeof(*enc->lf_stats_) + WEBP_ALIGN_CST : 0;
158 uint8_t* mem;
159 const uint64_t size = (uint64_t)sizeof(*enc) // main struct
160 + WEBP_ALIGN_CST // cache alignment
161 + info_size // modes info
162 + preds_size // prediction modes
163 + samples_size // top/left samples
164 + nz_size // coeff context bits
165 + lf_stats_size; // autofilter stats
166
167 #ifdef PRINT_MEMORY_INFO
168 printf("===================================\n");
169 printf("Memory used:\n"
170 " encoder: %ld\n"
171 " info: %ld\n"
172 " preds: %ld\n"
173 " top samples: %ld\n"
174 " non-zero: %ld\n"
175 " lf-stats: %ld\n"
176 " total: %ld\n",
177 sizeof(*enc) + WEBP_ALIGN_CST, info_size,
178 preds_size, samples_size, nz_size, lf_stats_size, size);
179 printf("Transient object sizes:\n"
180 " VP8EncIterator: %ld\n"
181 " VP8ModeScore: %ld\n"
182 " VP8SegmentInfo: %ld\n"
183 " VP8EncProba: %ld\n"
184 " LFStats: %ld\n",
185 sizeof(VP8EncIterator), sizeof(VP8ModeScore),
186 sizeof(VP8SegmentInfo), sizeof(VP8EncProba),
187 sizeof(LFStats));
188 printf("Picture size (yuv): %ld\n",
189 mb_w * mb_h * 384 * sizeof(uint8_t));
190 printf("===================================\n");
191 #endif
192 mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
193 if (mem == NULL) {
194 WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
195 return NULL;
196 }
197 enc = (VP8Encoder*)mem;
198 mem = (uint8_t*)WEBP_ALIGN(mem + sizeof(*enc));
199 memset(enc, 0, sizeof(*enc));
200 enc->num_parts_ = 1 << config->partitions;
201 enc->mb_w_ = mb_w;
202 enc->mb_h_ = mb_h;
203 enc->preds_w_ = preds_w;
204 enc->mb_info_ = (VP8MBInfo*)mem;
205 mem += info_size;
206 enc->preds_ = ((uint8_t*)mem) + 1 + enc->preds_w_;
207 mem += preds_size;
208 enc->nz_ = 1 + (uint32_t*)WEBP_ALIGN(mem);
209 mem += nz_size;
210 enc->lf_stats_ = lf_stats_size ? (LFStats*)WEBP_ALIGN(mem) : NULL;
211 mem += lf_stats_size;
212
213 // top samples (all 16-aligned)
214 mem = (uint8_t*)WEBP_ALIGN(mem);
215 enc->y_top_ = (uint8_t*)mem;
216 enc->uv_top_ = enc->y_top_ + top_stride;
217 mem += 2 * top_stride;
218 assert(mem <= (uint8_t*)enc + size);
219
220 enc->config_ = config;
221 enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
222 enc->pic_ = picture;
223 enc->percent_ = 0;
224
225 MapConfigToTools(enc);
226 VP8EncDspInit();
227 VP8DefaultProbas(enc);
228 ResetSegmentHeader(enc);
229 ResetFilterHeader(enc);
230 ResetBoundaryPredictions(enc);
231 VP8EncDspCostInit();
232 VP8EncInitAlpha(enc);
233
234 // lower quality means smaller output -> we modulate a little the page
235 // size based on quality. This is just a crude 1rst-order prediction.
236 {
237 const float scale = 1.f + config->quality * 5.f / 100.f; // in [1,6]
238 VP8TBufferInit(&enc->tokens_, (int)(mb_w * mb_h * 4 * scale));
239 }
240 return enc;
241 }
242
DeleteVP8Encoder(VP8Encoder * enc)243 static int DeleteVP8Encoder(VP8Encoder* enc) {
244 int ok = 1;
245 if (enc != NULL) {
246 ok = VP8EncDeleteAlpha(enc);
247 VP8TBufferClear(&enc->tokens_);
248 WebPSafeFree(enc);
249 }
250 return ok;
251 }
252
253 //------------------------------------------------------------------------------
254
GetPSNR(uint64_t err,uint64_t size)255 static double GetPSNR(uint64_t err, uint64_t size) {
256 return (err > 0 && size > 0) ? 10. * log10(255. * 255. * size / err) : 99.;
257 }
258
FinalizePSNR(const VP8Encoder * const enc)259 static void FinalizePSNR(const VP8Encoder* const enc) {
260 WebPAuxStats* stats = enc->pic_->stats;
261 const uint64_t size = enc->sse_count_;
262 const uint64_t* const sse = enc->sse_;
263 stats->PSNR[0] = (float)GetPSNR(sse[0], size);
264 stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
265 stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
266 stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
267 stats->PSNR[4] = (float)GetPSNR(sse[3], size);
268 }
269
StoreStats(VP8Encoder * const enc)270 static void StoreStats(VP8Encoder* const enc) {
271 WebPAuxStats* const stats = enc->pic_->stats;
272 if (stats != NULL) {
273 int i, s;
274 for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
275 stats->segment_level[i] = enc->dqm_[i].fstrength_;
276 stats->segment_quant[i] = enc->dqm_[i].quant_;
277 for (s = 0; s <= 2; ++s) {
278 stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
279 }
280 }
281 FinalizePSNR(enc);
282 stats->coded_size = enc->coded_size_;
283 for (i = 0; i < 3; ++i) {
284 stats->block_count[i] = enc->block_count_[i];
285 }
286 }
287 WebPReportProgress(enc->pic_, 100, &enc->percent_); // done!
288 }
289
WebPEncodingSetError(const WebPPicture * const pic,WebPEncodingError error)290 int WebPEncodingSetError(const WebPPicture* const pic,
291 WebPEncodingError error) {
292 assert((int)error < VP8_ENC_ERROR_LAST);
293 assert((int)error >= VP8_ENC_OK);
294 ((WebPPicture*)pic)->error_code = error;
295 return 0;
296 }
297
WebPReportProgress(const WebPPicture * const pic,int percent,int * const percent_store)298 int WebPReportProgress(const WebPPicture* const pic,
299 int percent, int* const percent_store) {
300 if (percent_store != NULL && percent != *percent_store) {
301 *percent_store = percent;
302 if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
303 // user abort requested
304 WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
305 return 0;
306 }
307 }
308 return 1; // ok
309 }
310 //------------------------------------------------------------------------------
311
WebPEncode(const WebPConfig * config,WebPPicture * pic)312 int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
313 int ok = 0;
314
315 if (pic == NULL)
316 return 0;
317 WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
318 if (config == NULL) // bad params
319 return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
320 if (!WebPValidateConfig(config))
321 return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
322 if (pic->width <= 0 || pic->height <= 0)
323 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
324 if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION)
325 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
326
327 if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
328
329 if (!config->lossless) {
330 VP8Encoder* enc = NULL;
331
332 if (!config->exact) {
333 WebPCleanupTransparentArea(pic);
334 }
335
336 if (pic->use_argb || pic->y == NULL || pic->u == NULL || pic->v == NULL) {
337 // Make sure we have YUVA samples.
338 if (config->preprocessing & 4) {
339 if (!WebPPictureSmartARGBToYUVA(pic)) {
340 return 0;
341 }
342 } else {
343 float dithering = 0.f;
344 if (config->preprocessing & 2) {
345 const float x = config->quality / 100.f;
346 const float x2 = x * x;
347 // slowly decreasing from max dithering at low quality (q->0)
348 // to 0.5 dithering amplitude at high quality (q->100)
349 dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;
350 }
351 if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {
352 return 0;
353 }
354 }
355 }
356
357 enc = InitVP8Encoder(config, pic);
358 if (enc == NULL) return 0; // pic->error is already set.
359 // Note: each of the tasks below account for 20% in the progress report.
360 ok = VP8EncAnalyze(enc);
361
362 // Analysis is done, proceed to actual coding.
363 ok = ok && VP8EncStartAlpha(enc); // possibly done in parallel
364 if (!enc->use_tokens_) {
365 ok = ok && VP8EncLoop(enc);
366 } else {
367 ok = ok && VP8EncTokenLoop(enc);
368 }
369 ok = ok && VP8EncFinishAlpha(enc);
370
371 ok = ok && VP8EncWrite(enc);
372 StoreStats(enc);
373 if (!ok) {
374 VP8EncFreeBitWriters(enc);
375 }
376 ok &= DeleteVP8Encoder(enc); // must always be called, even if !ok
377 } else {
378 // Make sure we have ARGB samples.
379 if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {
380 return 0;
381 }
382
383 if (!config->exact) {
384 WebPCleanupTransparentAreaLossless(pic);
385 }
386
387 ok = VP8LEncodeImage(config, pic); // Sets pic->error in case of problem.
388 }
389
390 return ok;
391 }
392