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 "src/enc/cost_enc.h"
20#include "src/enc/vp8i_enc.h"
21#include "src/enc/vp8li_enc.h"
22#include "src/utils/utils.h"
23
24// #define PRINT_MEMORY_INFO
25
26#ifdef PRINT_MEMORY_INFO
27#include <stdio.h>
28#endif
29
30//------------------------------------------------------------------------------
31
32int WebPGetEncoderVersion(void) {
33 return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
34}
35
36//------------------------------------------------------------------------------
37// VP8Encoder
38//------------------------------------------------------------------------------
39
40static 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
47static 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
55static 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 | 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
95static 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 // partition0 = 512k max.
109 enc->mb_header_limit_ =
110 (score_t)256 * 510 * 8 * 1024 / (enc->mb_w_ * enc->mb_h_);
111
112 enc->thread_level_ = config->thread_level;
113
114 enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
115 if (!config->low_memory) {
116#if !defined(DISABLE_TOKEN_BUFFER)
117 enc->use_tokens_ = (enc->rd_opt_level_ >= RD_OPT_BASIC); // need rd stats
118#endif
119 if (enc->use_tokens_) {
120 enc->num_parts_ = 1; // doesn't work with multi-partition
121 }
122 }
123}
124
125// Memory scaling with dimensions:
126// memory (bytes) ~= 2.25 * w + 0.0625 * w * h
127//
128// Typical memory footprint (614x440 picture)
129// encoder: 22111
130// info: 4368
131// preds: 17741
132// top samples: 1263
133// non-zero: 175
134// lf-stats: 0
135// total: 45658
136// Transient object sizes:
137// VP8EncIterator: 3360
138// VP8ModeScore: 872
139// VP8SegmentInfo: 732
140// VP8EncProba: 18352
141// LFStats: 2048
142// Picture size (yuv): 419328
143
144static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
145 WebPPicture* const picture) {
146 VP8Encoder* enc;
147 const int use_filter =
148 (config->filter_strength > 0) || (config->autofilter > 0);
149 const int mb_w = (picture->width + 15) >> 4;
150 const int mb_h = (picture->height + 15) >> 4;
151 const int preds_w = 4 * mb_w + 1;
152 const int preds_h = 4 * mb_h + 1;
153 const size_t preds_size = preds_w * preds_h * sizeof(*enc->preds_);
154 const int top_stride = mb_w * 16;
155 const size_t nz_size = (mb_w + 1) * sizeof(*enc->nz_) + WEBP_ALIGN_CST;
156 const size_t info_size = mb_w * mb_h * sizeof(*enc->mb_info_);
157 const size_t samples_size =
158 2 * top_stride * sizeof(*enc->y_top_) // top-luma/u/v
159 + WEBP_ALIGN_CST; // align all
160 const size_t lf_stats_size =
161 config->autofilter ? sizeof(*enc->lf_stats_) + WEBP_ALIGN_CST : 0;
162 const size_t top_derr_size =
163 (config->quality <= ERROR_DIFFUSION_QUALITY || config->pass > 1) ?
164 mb_w * sizeof(*enc->top_derr_) : 0;
165 uint8_t* mem;
166 const uint64_t size = (uint64_t)sizeof(*enc) // main struct
167 + WEBP_ALIGN_CST // cache alignment
168 + info_size // modes info
169 + preds_size // prediction modes
170 + samples_size // top/left samples
171 + top_derr_size // top diffusion error
172 + nz_size // coeff context bits
173 + lf_stats_size; // autofilter stats
174
175#ifdef PRINT_MEMORY_INFO
176 printf("===================================\n");
177 printf("Memory used:\n"
178 " encoder: %ld\n"
179 " info: %ld\n"
180 " preds: %ld\n"
181 " top samples: %ld\n"
182 " top diffusion: %ld\n"
183 " non-zero: %ld\n"
184 " lf-stats: %ld\n"
185 " total: %ld\n",
186 sizeof(*enc) + WEBP_ALIGN_CST, info_size,
187 preds_size, samples_size, top_derr_size, nz_size, lf_stats_size, size);
188 printf("Transient object sizes:\n"
189 " VP8EncIterator: %ld\n"
190 " VP8ModeScore: %ld\n"
191 " VP8SegmentInfo: %ld\n"
192 " VP8EncProba: %ld\n"
193 " LFStats: %ld\n",
194 sizeof(VP8EncIterator), sizeof(VP8ModeScore),
195 sizeof(VP8SegmentInfo), sizeof(VP8EncProba),
196 sizeof(LFStats));
197 printf("Picture size (yuv): %ld\n",
198 mb_w * mb_h * 384 * sizeof(uint8_t));
199 printf("===================================\n");
200#endif
201 mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
202 if (mem == NULL) {
203 WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
204 return NULL;
205 }
206 enc = (VP8Encoder*)mem;
207 mem = (uint8_t*)WEBP_ALIGN(mem + sizeof(*enc));
208 memset(enc, 0, sizeof(*enc));
209 enc->num_parts_ = 1 << config->partitions;
210 enc->mb_w_ = mb_w;
211 enc->mb_h_ = mb_h;
212 enc->preds_w_ = preds_w;
213 enc->mb_info_ = (VP8MBInfo*)mem;
214 mem += info_size;
215 enc->preds_ = mem + 1 + enc->preds_w_;
216 mem += preds_size;
217 enc->nz_ = 1 + (uint32_t*)WEBP_ALIGN(mem);
218 mem += nz_size;
219 enc->lf_stats_ = lf_stats_size ? (LFStats*)WEBP_ALIGN(mem) : NULL;
220 mem += lf_stats_size;
221
222 // top samples (all 16-aligned)
223 mem = (uint8_t*)WEBP_ALIGN(mem);
224 enc->y_top_ = mem;
225 enc->uv_top_ = enc->y_top_ + top_stride;
226 mem += 2 * top_stride;
227 enc->top_derr_ = top_derr_size ? (DError*)mem : NULL;
228 mem += top_derr_size;
229 assert(mem <= (uint8_t*)enc + size);
230
231 enc->config_ = config;
232 enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
233 enc->pic_ = picture;
234 enc->percent_ = 0;
235
236 MapConfigToTools(enc);
237 VP8EncDspInit();
238 VP8DefaultProbas(enc);
239 ResetSegmentHeader(enc);
240 ResetFilterHeader(enc);
241 ResetBoundaryPredictions(enc);
242 VP8EncDspCostInit();
243 VP8EncInitAlpha(enc);
244
245 // lower quality means smaller output -> we modulate a little the page
246 // size based on quality. This is just a crude 1rst-order prediction.
247 {
248 const float scale = 1.f + config->quality * 5.f / 100.f; // in [1,6]
249 VP8TBufferInit(&enc->tokens_, (int)(mb_w * mb_h * 4 * scale));
250 }
251 return enc;
252}
253
254static int DeleteVP8Encoder(VP8Encoder* enc) {
255 int ok = 1;
256 if (enc != NULL) {
257 ok = VP8EncDeleteAlpha(enc);
258 VP8TBufferClear(&enc->tokens_);
259 WebPSafeFree(enc);
260 }
261 return ok;
262}
263
264//------------------------------------------------------------------------------
265
266#if !defined(WEBP_DISABLE_STATS)
267static double GetPSNR(uint64_t err, uint64_t size) {
268 return (err > 0 && size > 0) ? 10. * log10(255. * 255. * size / err) : 99.;
269}
270
271static void FinalizePSNR(const VP8Encoder* const enc) {
272 WebPAuxStats* stats = enc->pic_->stats;
273 const uint64_t size = enc->sse_count_;
274 const uint64_t* const sse = enc->sse_;
275 stats->PSNR[0] = (float)GetPSNR(sse[0], size);
276 stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
277 stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
278 stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
279 stats->PSNR[4] = (float)GetPSNR(sse[3], size);
280}
281#endif // !defined(WEBP_DISABLE_STATS)
282
283static void StoreStats(VP8Encoder* const enc) {
284#if !defined(WEBP_DISABLE_STATS)
285 WebPAuxStats* const stats = enc->pic_->stats;
286 if (stats != NULL) {
287 int i, s;
288 for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
289 stats->segment_level[i] = enc->dqm_[i].fstrength_;
290 stats->segment_quant[i] = enc->dqm_[i].quant_;
291 for (s = 0; s <= 2; ++s) {
292 stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
293 }
294 }
295 FinalizePSNR(enc);
296 stats->coded_size = enc->coded_size_;
297 for (i = 0; i < 3; ++i) {
298 stats->block_count[i] = enc->block_count_[i];
299 }
300 }
301#else // defined(WEBP_DISABLE_STATS)
302 WebPReportProgress(enc->pic_, 100, &enc->percent_); // done!
303#endif // !defined(WEBP_DISABLE_STATS)
304}
305
306int WebPEncodingSetError(const WebPPicture* const pic,
307 WebPEncodingError error) {
308 assert((int)error < VP8_ENC_ERROR_LAST);
309 assert((int)error >= VP8_ENC_OK);
310 ((WebPPicture*)pic)->error_code = error;
311 return 0;
312}
313
314int WebPReportProgress(const WebPPicture* const pic,
315 int percent, int* const percent_store) {
316 if (percent_store != NULL && percent != *percent_store) {
317 *percent_store = percent;
318 if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
319 // user abort requested
320 WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
321 return 0;
322 }
323 }
324 return 1; // ok
325}
326//------------------------------------------------------------------------------
327
328int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
329 int ok = 0;
330 if (pic == NULL) return 0;
331
332 WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
333 if (config == NULL) { // bad params
334 return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
335 }
336 if (!WebPValidateConfig(config)) {
337 return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
338 }
339 if (pic->width <= 0 || pic->height <= 0) {
340 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
341 }
342 if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION) {
343 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
344 }
345
346 if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
347
348 if (!config->lossless) {
349 VP8Encoder* enc = NULL;
350
351 if (pic->use_argb || pic->y == NULL || pic->u == NULL || pic->v == NULL) {
352 // Make sure we have YUVA samples.
353 if (config->use_sharp_yuv || (config->preprocessing & 4)) {
354 if (!WebPPictureSharpARGBToYUVA(pic)) {
355 return 0;
356 }
357 } else {
358 float dithering = 0.f;
359 if (config->preprocessing & 2) {
360 const float x = config->quality / 100.f;
361 const float x2 = x * x;
362 // slowly decreasing from max dithering at low quality (q->0)
363 // to 0.5 dithering amplitude at high quality (q->100)
364 dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;
365 }
366 if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {
367 return 0;
368 }
369 }
370 }
371
372 if (!config->exact) {
373 WebPCleanupTransparentArea(pic);
374 }
375
376 enc = InitVP8Encoder(config, pic);
377 if (enc == NULL) return 0; // pic->error is already set.
378 // Note: each of the tasks below account for 20% in the progress report.
379 ok = VP8EncAnalyze(enc);
380
381 // Analysis is done, proceed to actual coding.
382 ok = ok && VP8EncStartAlpha(enc); // possibly done in parallel
383 if (!enc->use_tokens_) {
384 ok = ok && VP8EncLoop(enc);
385 } else {
386 ok = ok && VP8EncTokenLoop(enc);
387 }
388 ok = ok && VP8EncFinishAlpha(enc);
389
390 ok = ok && VP8EncWrite(enc);
391 StoreStats(enc);
392 if (!ok) {
393 VP8EncFreeBitWriters(enc);
394 }
395 ok &= DeleteVP8Encoder(enc); // must always be called, even if !ok
396 } else {
397 // Make sure we have ARGB samples.
398 if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {
399 return 0;
400 }
401
402 if (!config->exact) {
403 WebPCleanupTransparentAreaLossless(pic);
404 }
405
406 ok = VP8LEncodeImage(config, pic); // Sets pic->error in case of problem.
407 }
408
409 return ok;
410}
411