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 "./vp8enci.h"
20 #include "./vp8li.h"
21 #include "./cost.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 VP8SegmentHeader* 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 VP8FilterHeader* 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-score i4/16 | | | x | | | | |
83 //-------------------+---+---+---+---+---+---+---+
84 // rd-opt i4/16 | | | ~ | x | x | x | x |
85 //-------------------+---+---+---+---+---+---+---+
86 // token buffer (opt)| | | | x | x | x | x |
87 //-------------------+---+---+---+---+---+---+---+
88 // Trellis | | | | | | x |Ful|
89 //-------------------+---+---+---+---+---+---+---+
90 // full-SNS | | | | | x | x | x |
91 //-------------------+---+---+---+---+---+---+---+
92
MapConfigToTools(VP8Encoder * const enc)93 static void MapConfigToTools(VP8Encoder* const enc) {
94 const WebPConfig* const config = enc->config_;
95 const int method = config->method;
96 const int limit = 100 - config->partition_limit;
97 enc->method_ = method;
98 enc->rd_opt_level_ = (method >= 6) ? RD_OPT_TRELLIS_ALL
99 : (method >= 5) ? RD_OPT_TRELLIS
100 : (method >= 3) ? RD_OPT_BASIC
101 : RD_OPT_NONE;
102 enc->max_i4_header_bits_ =
103 256 * 16 * 16 * // upper bound: up to 16bit per 4x4 block
104 (limit * limit) / (100 * 100); // ... modulated with a quadratic curve.
105
106 enc->thread_level_ = config->thread_level;
107
108 enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
109 if (!config->low_memory) {
110 #if !defined(DISABLE_TOKEN_BUFFER)
111 enc->use_tokens_ = (enc->rd_opt_level_ >= RD_OPT_BASIC); // need rd stats
112 #endif
113 if (enc->use_tokens_) {
114 enc->num_parts_ = 1; // doesn't work with multi-partition
115 }
116 }
117 }
118
119 // Memory scaling with dimensions:
120 // memory (bytes) ~= 2.25 * w + 0.0625 * w * h
121 //
122 // Typical memory footprint (614x440 picture)
123 // encoder: 22111
124 // info: 4368
125 // preds: 17741
126 // top samples: 1263
127 // non-zero: 175
128 // lf-stats: 0
129 // total: 45658
130 // Transient object sizes:
131 // VP8EncIterator: 3360
132 // VP8ModeScore: 872
133 // VP8SegmentInfo: 732
134 // VP8Proba: 18352
135 // LFStats: 2048
136 // Picture size (yuv): 419328
137
InitVP8Encoder(const WebPConfig * const config,WebPPicture * const picture)138 static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
139 WebPPicture* const picture) {
140 const int use_filter =
141 (config->filter_strength > 0) || (config->autofilter > 0);
142 const int mb_w = (picture->width + 15) >> 4;
143 const int mb_h = (picture->height + 15) >> 4;
144 const int preds_w = 4 * mb_w + 1;
145 const int preds_h = 4 * mb_h + 1;
146 const size_t preds_size = preds_w * preds_h * sizeof(uint8_t);
147 const int top_stride = mb_w * 16;
148 const size_t nz_size = (mb_w + 1) * sizeof(uint32_t) + ALIGN_CST;
149 const size_t info_size = mb_w * mb_h * sizeof(VP8MBInfo);
150 const size_t samples_size = 2 * top_stride * sizeof(uint8_t) // top-luma/u/v
151 + ALIGN_CST; // align all
152 const size_t lf_stats_size =
153 config->autofilter ? sizeof(LFStats) + ALIGN_CST : 0;
154 VP8Encoder* enc;
155 uint8_t* mem;
156 const uint64_t size = (uint64_t)sizeof(VP8Encoder) // main struct
157 + ALIGN_CST // cache alignment
158 + info_size // modes info
159 + preds_size // prediction modes
160 + samples_size // top/left samples
161 + nz_size // coeff context bits
162 + lf_stats_size; // autofilter stats
163
164 #ifdef PRINT_MEMORY_INFO
165 printf("===================================\n");
166 printf("Memory used:\n"
167 " encoder: %ld\n"
168 " info: %ld\n"
169 " preds: %ld\n"
170 " top samples: %ld\n"
171 " non-zero: %ld\n"
172 " lf-stats: %ld\n"
173 " total: %ld\n",
174 sizeof(VP8Encoder) + ALIGN_CST, info_size,
175 preds_size, samples_size, nz_size, lf_stats_size, size);
176 printf("Transient object sizes:\n"
177 " VP8EncIterator: %ld\n"
178 " VP8ModeScore: %ld\n"
179 " VP8SegmentInfo: %ld\n"
180 " VP8Proba: %ld\n"
181 " LFStats: %ld\n",
182 sizeof(VP8EncIterator), sizeof(VP8ModeScore),
183 sizeof(VP8SegmentInfo), sizeof(VP8Proba),
184 sizeof(LFStats));
185 printf("Picture size (yuv): %ld\n",
186 mb_w * mb_h * 384 * sizeof(uint8_t));
187 printf("===================================\n");
188 #endif
189 mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
190 if (mem == NULL) {
191 WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
192 return NULL;
193 }
194 enc = (VP8Encoder*)mem;
195 mem = (uint8_t*)DO_ALIGN(mem + sizeof(*enc));
196 memset(enc, 0, sizeof(*enc));
197 enc->num_parts_ = 1 << config->partitions;
198 enc->mb_w_ = mb_w;
199 enc->mb_h_ = mb_h;
200 enc->preds_w_ = preds_w;
201 enc->mb_info_ = (VP8MBInfo*)mem;
202 mem += info_size;
203 enc->preds_ = ((uint8_t*)mem) + 1 + enc->preds_w_;
204 mem += preds_w * preds_h * sizeof(uint8_t);
205 enc->nz_ = 1 + (uint32_t*)DO_ALIGN(mem);
206 mem += nz_size;
207 enc->lf_stats_ = lf_stats_size ? (LFStats*)DO_ALIGN(mem) : NULL;
208 mem += lf_stats_size;
209
210 // top samples (all 16-aligned)
211 mem = (uint8_t*)DO_ALIGN(mem);
212 enc->y_top_ = (uint8_t*)mem;
213 enc->uv_top_ = enc->y_top_ + top_stride;
214 mem += 2 * top_stride;
215 assert(mem <= (uint8_t*)enc + size);
216
217 enc->config_ = config;
218 enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
219 enc->pic_ = picture;
220 enc->percent_ = 0;
221
222 MapConfigToTools(enc);
223 VP8EncDspInit();
224 VP8DefaultProbas(enc);
225 ResetSegmentHeader(enc);
226 ResetFilterHeader(enc);
227 ResetBoundaryPredictions(enc);
228 VP8GetResidualCostInit();
229 VP8SetResidualCoeffsInit();
230 VP8EncInitAlpha(enc);
231
232 // lower quality means smaller output -> we modulate a little the page
233 // size based on quality. This is just a crude 1rst-order prediction.
234 {
235 const float scale = 1.f + config->quality * 5.f / 100.f; // in [1,6]
236 VP8TBufferInit(&enc->tokens_, (int)(mb_w * mb_h * 4 * scale));
237 }
238 return enc;
239 }
240
DeleteVP8Encoder(VP8Encoder * enc)241 static int DeleteVP8Encoder(VP8Encoder* enc) {
242 int ok = 1;
243 if (enc != NULL) {
244 ok = VP8EncDeleteAlpha(enc);
245 VP8TBufferClear(&enc->tokens_);
246 WebPSafeFree(enc);
247 }
248 return ok;
249 }
250
251 //------------------------------------------------------------------------------
252
GetPSNR(uint64_t err,uint64_t size)253 static double GetPSNR(uint64_t err, uint64_t size) {
254 return (err > 0 && size > 0) ? 10. * log10(255. * 255. * size / err) : 99.;
255 }
256
FinalizePSNR(const VP8Encoder * const enc)257 static void FinalizePSNR(const VP8Encoder* const enc) {
258 WebPAuxStats* stats = enc->pic_->stats;
259 const uint64_t size = enc->sse_count_;
260 const uint64_t* const sse = enc->sse_;
261 stats->PSNR[0] = (float)GetPSNR(sse[0], size);
262 stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
263 stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
264 stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
265 stats->PSNR[4] = (float)GetPSNR(sse[3], size);
266 }
267
StoreStats(VP8Encoder * const enc)268 static void StoreStats(VP8Encoder* const enc) {
269 WebPAuxStats* const stats = enc->pic_->stats;
270 if (stats != NULL) {
271 int i, s;
272 for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
273 stats->segment_level[i] = enc->dqm_[i].fstrength_;
274 stats->segment_quant[i] = enc->dqm_[i].quant_;
275 for (s = 0; s <= 2; ++s) {
276 stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
277 }
278 }
279 FinalizePSNR(enc);
280 stats->coded_size = enc->coded_size_;
281 for (i = 0; i < 3; ++i) {
282 stats->block_count[i] = enc->block_count_[i];
283 }
284 }
285 WebPReportProgress(enc->pic_, 100, &enc->percent_); // done!
286 }
287
WebPEncodingSetError(const WebPPicture * const pic,WebPEncodingError error)288 int WebPEncodingSetError(const WebPPicture* const pic,
289 WebPEncodingError error) {
290 assert((int)error < VP8_ENC_ERROR_LAST);
291 assert((int)error >= VP8_ENC_OK);
292 ((WebPPicture*)pic)->error_code = error;
293 return 0;
294 }
295
WebPReportProgress(const WebPPicture * const pic,int percent,int * const percent_store)296 int WebPReportProgress(const WebPPicture* const pic,
297 int percent, int* const percent_store) {
298 if (percent_store != NULL && percent != *percent_store) {
299 *percent_store = percent;
300 if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
301 // user abort requested
302 WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
303 return 0;
304 }
305 }
306 return 1; // ok
307 }
308 //------------------------------------------------------------------------------
309
WebPEncode(const WebPConfig * config,WebPPicture * pic)310 int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
311 int ok = 0;
312
313 if (pic == NULL)
314 return 0;
315 WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
316 if (config == NULL) // bad params
317 return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
318 if (!WebPValidateConfig(config))
319 return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
320 if (pic->width <= 0 || pic->height <= 0)
321 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
322 if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION)
323 return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
324
325 if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
326
327 if (!config->lossless) {
328 VP8Encoder* enc = NULL;
329 if (pic->y == NULL || pic->u == NULL || pic->v == NULL) {
330 // Make sure we have YUVA samples.
331 if (config->preprocessing & 4) {
332 #if WEBP_ENCODER_ABI_VERSION > 0x0204
333 if (!WebPPictureSmartARGBToYUVA(pic)) {
334 return 0;
335 }
336 #endif
337 } else {
338 float dithering = 0.f;
339 if (config->preprocessing & 2) {
340 const float x = config->quality / 100.f;
341 const float x2 = x * x;
342 // slowly decreasing from max dithering at low quality (q->0)
343 // to 0.5 dithering amplitude at high quality (q->100)
344 dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;
345 }
346 if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {
347 return 0;
348 }
349 }
350 }
351
352 enc = InitVP8Encoder(config, pic);
353 if (enc == NULL) return 0; // pic->error is already set.
354 // Note: each of the tasks below account for 20% in the progress report.
355 ok = VP8EncAnalyze(enc);
356
357 // Analysis is done, proceed to actual coding.
358 ok = ok && VP8EncStartAlpha(enc); // possibly done in parallel
359 if (!enc->use_tokens_) {
360 ok = ok && VP8EncLoop(enc);
361 } else {
362 ok = ok && VP8EncTokenLoop(enc);
363 }
364 ok = ok && VP8EncFinishAlpha(enc);
365
366 ok = ok && VP8EncWrite(enc);
367 StoreStats(enc);
368 if (!ok) {
369 VP8EncFreeBitWriters(enc);
370 }
371 ok &= DeleteVP8Encoder(enc); // must always be called, even if !ok
372 } else {
373 // Make sure we have ARGB samples.
374 if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {
375 return 0;
376 }
377
378 ok = VP8LEncodeImage(config, pic); // Sets pic->error in case of problem.
379 }
380
381 return ok;
382 }
383