Enable decoding of more mpeg-ts streams for pcHDTV patch by (Doug Larrick <doug at...
[libav.git] / libavcodec / utils.c
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1/*
2 * utils for libavcodec
ff4ec49e 3 * Copyright (c) 2001 Fabrice Bellard.
de6d9b64 4 *
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5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
de6d9b64 9 *
ff4ec49e 10 * This library is distributed in the hope that it will be useful,
de6d9b64 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
de6d9b64 14 *
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15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
de6d9b64 18 */
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19
20/**
21 * @file utils.c
22 * utils.
23 */
24
de6d9b64 25#include "avcodec.h"
3123dd79 26#include "dsputil.h"
1c2a8c7f 27#include "mpegvideo.h"
de6d9b64 28
18f77016 29void *av_mallocz(unsigned int size)
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30{
31 void *ptr;
5b20b732 32
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33 ptr = av_malloc(size);
34 if (!ptr)
35 return NULL;
36 memset(ptr, 0, size);
37 return ptr;
38}
39
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40char *av_strdup(const char *s)
41{
42 char *ptr;
43 int len;
44 len = strlen(s) + 1;
45 ptr = av_malloc(len);
46 if (!ptr)
47 return NULL;
48 memcpy(ptr, s, len);
49 return ptr;
50}
51
52/**
53 * realloc which does nothing if the block is large enough
54 */
5c91a675 55void *av_fast_realloc(void *ptr, unsigned int *size, unsigned int min_size)
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56{
57 if(min_size < *size)
58 return ptr;
59
60 *size= min_size + 10*1024;
61
62 return av_realloc(ptr, *size);
63}
64
65
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66/* allocation of static arrays - do not use for normal allocation */
67static unsigned int last_static = 0;
68static char*** array_static = NULL;
69static const unsigned int grow_static = 64; // ^2
70void *__av_mallocz_static(void** location, unsigned int size)
71{
5c91a675 72 unsigned int l = (last_static + grow_static) & ~(grow_static - 1);
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73 void *ptr = av_mallocz(size);
74 if (!ptr)
75 return NULL;
76
77 if (location)
78 {
79 if (l > last_static)
8e1e6f31 80 array_static = av_realloc(array_static, l);
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81 array_static[last_static++] = (char**) location;
82 *location = ptr;
83 }
84 return ptr;
85}
86/* free all static arrays and reset pointers to 0 */
4cfbf61b 87void av_free_static(void)
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88{
89 if (array_static)
90 {
91 unsigned i;
92 for (i = 0; i < last_static; i++)
93 {
8e1e6f31 94 av_free(*array_static[i]);
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95 *array_static[i] = NULL;
96 }
8e1e6f31 97 av_free(array_static);
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98 array_static = 0;
99 }
100 last_static = 0;
101}
102
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103/* cannot call it directly because of 'void **' casting is not automatic */
104void __av_freep(void **ptr)
105{
106 av_free(*ptr);
107 *ptr = NULL;
108}
109
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110/* encoder management */
111AVCodec *first_avcodec;
112
113void register_avcodec(AVCodec *format)
114{
115 AVCodec **p;
116 p = &first_avcodec;
117 while (*p != NULL) p = &(*p)->next;
118 *p = format;
119 format->next = NULL;
120}
121
d90cf87b 122typedef struct InternalBuffer{
1e491e29 123 int last_pic_num;
d90cf87b 124 uint8_t *base[4];
1e491e29 125 uint8_t *data[4];
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126}InternalBuffer;
127
128#define INTERNAL_BUFFER_SIZE 32
1e491e29 129
492cd3a9 130int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic){
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131 int i;
132 const int width = s->width;
133 const int height= s->height;
d90cf87b 134 InternalBuffer *buf;
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135
136 assert(pic->data[0]==NULL);
d90cf87b 137 assert(INTERNAL_BUFFER_SIZE > s->internal_buffer_count);
1e491e29 138
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139 if(s->internal_buffer==NULL){
140 s->internal_buffer= av_mallocz(INTERNAL_BUFFER_SIZE*sizeof(InternalBuffer));
141 }
142#if 0
143 s->internal_buffer= av_fast_realloc(
144 s->internal_buffer,
145 &s->internal_buffer_size,
146 sizeof(InternalBuffer)*FFMAX(99, s->internal_buffer_count+1)/*FIXME*/
147 );
148#endif
149
150 buf= &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
151
152 if(buf->base[0]){
153 pic->age= pic->coded_picture_number - buf->last_pic_num;
154 buf->last_pic_num= pic->coded_picture_number;
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155 }else{
156 int align, h_chroma_shift, v_chroma_shift;
157 int w, h, pixel_size;
158
159 avcodec_get_chroma_sub_sample(s->pix_fmt, &h_chroma_shift, &v_chroma_shift);
1e491e29 160 switch(s->pix_fmt){
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161 case PIX_FMT_RGB555:
162 case PIX_FMT_RGB565:
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163 case PIX_FMT_YUV422:
164 pixel_size=2;
165 break;
166 case PIX_FMT_RGB24:
167 case PIX_FMT_BGR24:
168 pixel_size=3;
169 break;
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170 case PIX_FMT_RGBA32:
171 pixel_size=4;
172 break;
173 default:
174 pixel_size=1;
175 }
176
177 if(s->codec_id==CODEC_ID_SVQ1) align=63;
178 else align=15;
179
180 w= (width +align)&~align;
181 h= (height+align)&~align;
182
183 if(!(s->flags&CODEC_FLAG_EMU_EDGE)){
184 w+= EDGE_WIDTH*2;
185 h+= EDGE_WIDTH*2;
186 }
187
d90cf87b 188 buf->last_pic_num= -256*256*256*64;
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189
190 for(i=0; i<3; i++){
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191 const int h_shift= i==0 ? 0 : h_chroma_shift;
192 const int v_shift= i==0 ? 0 : v_chroma_shift;
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193
194 pic->linesize[i]= pixel_size*w>>h_shift;
195
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196 buf->base[i]= av_mallocz((pic->linesize[i]*h>>v_shift)+16); //FIXME 16
197 if(buf->base[i]==NULL) return -1;
198 memset(buf->base[i], 128, pic->linesize[i]*h>>v_shift);
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199
200 if(s->flags&CODEC_FLAG_EMU_EDGE)
d90cf87b 201 buf->data[i] = buf->base[i];
1e491e29 202 else
d90cf87b 203 buf->data[i] = buf->base[i] + (pic->linesize[i]*EDGE_WIDTH>>v_shift) + (EDGE_WIDTH>>h_shift);
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204 }
205 pic->age= 256*256*256*64;
4e00e76b 206 pic->type= FF_BUFFER_TYPE_INTERNAL;
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207 }
208
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209 for(i=0; i<4; i++){
210 pic->base[i]= buf->base[i];
211 pic->data[i]= buf->data[i];
212 }
213 s->internal_buffer_count++;
214
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215 return 0;
216}
217
492cd3a9 218void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
1e491e29 219 int i;
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220 InternalBuffer *buf, *last, temp;
221
4e00e76b 222 assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
59c673d5 223 assert(s->internal_buffer_count);
d90cf87b 224
b1609412 225 buf = NULL; /* avoids warning */
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226 for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
227 buf= &((InternalBuffer*)s->internal_buffer)[i];
228 if(buf->data[0] == pic->data[0])
229 break;
230 }
231 assert(i < s->internal_buffer_count);
232 s->internal_buffer_count--;
233 last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
234
235 temp= *buf;
236 *buf= *last;
237 *last= temp;
238
239 for(i=0; i<3; i++){
1e491e29 240 pic->data[i]=NULL;
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241// pic->base[i]=NULL;
242 }
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243//printf("R%X\n", pic->opaque);
244}
245
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246enum PixelFormat avcodec_default_get_format(struct AVCodecContext *s, enum PixelFormat * fmt){
247 return fmt[0];
248}
249
a949d72e 250void avcodec_get_context_defaults(AVCodecContext *s){
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251 s->bit_rate= 800*1000;
252 s->bit_rate_tolerance= s->bit_rate*10;
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253 s->qmin= 2;
254 s->qmax= 31;
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255 s->mb_qmin= 2;
256 s->mb_qmax= 31;
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257 s->rc_eq= "tex^qComp";
258 s->qcompress= 0.5;
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259 s->max_qdiff= 3;
260 s->b_quant_factor=1.25;
261 s->b_quant_offset=1.25;
b3a391e8 262 s->i_quant_factor=-0.8;
e8b62df6 263 s->i_quant_offset=0.0;
4d2858de 264 s->error_concealment= 3;
8d0e42ca 265 s->error_resilience= 1;
4d2858de 266 s->workaround_bugs= FF_BUG_AUTODETECT;
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267 s->frame_rate_base= 1;
268 s->frame_rate = 25;
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269 s->gop_size= 50;
270 s->me_method= ME_EPZS;
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271 s->get_buffer= avcodec_default_get_buffer;
272 s->release_buffer= avcodec_default_release_buffer;
a33c7159 273 s->get_format= avcodec_default_get_format;
826f429a 274 s->me_subpel_quality=8;
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275 s->lmin= FF_QP2LAMBDA * s->qmin;
276 s->lmax= FF_QP2LAMBDA * s->qmax;
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277
278 s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
279 s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;
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280}
281
282/**
283 * allocates a AVCodecContext and set it to defaults.
284 * this can be deallocated by simply calling free()
285 */
7ffbb60e 286AVCodecContext *avcodec_alloc_context(void){
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287 AVCodecContext *avctx= av_mallocz(sizeof(AVCodecContext));
288
289 if(avctx==NULL) return NULL;
290
291 avcodec_get_context_defaults(avctx);
292
293 return avctx;
294}
295
1e491e29 296/**
492cd3a9 297 * allocates a AVPFrame and set it to defaults.
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298 * this can be deallocated by simply calling free()
299 */
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300AVFrame *avcodec_alloc_frame(void){
301 AVFrame *pic= av_mallocz(sizeof(AVFrame));
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302
303 return pic;
304}
305
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306int avcodec_open(AVCodecContext *avctx, AVCodec *codec)
307{
308 int ret;
309
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310 if(avctx->codec)
311 return -1;
312
de6d9b64 313 avctx->codec = codec;
4cb3ca72 314 avctx->codec_id = codec->id;
de6d9b64 315 avctx->frame_number = 0;
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316 if (codec->priv_data_size > 0) {
317 avctx->priv_data = av_mallocz(codec->priv_data_size);
318 if (!avctx->priv_data)
319 return -ENOMEM;
320 } else {
321 avctx->priv_data = NULL;
322 }
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323 ret = avctx->codec->init(avctx);
324 if (ret < 0) {
3123dd79 325 av_freep(&avctx->priv_data);
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326 return ret;
327 }
328 return 0;
329}
330
0c1a9eda 331int avcodec_encode_audio(AVCodecContext *avctx, uint8_t *buf, int buf_size,
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332 const short *samples)
333{
334 int ret;
335
336 ret = avctx->codec->encode(avctx, buf, buf_size, (void *)samples);
337 avctx->frame_number++;
338 return ret;
339}
340
0c1a9eda 341int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
492cd3a9 342 const AVFrame *pict)
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343{
344 int ret;
345
346 ret = avctx->codec->encode(avctx, buf, buf_size, (void *)pict);
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347
348 emms_c(); //needed to avoid a emms_c() call before every return;
349
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350 avctx->frame_number++;
351 return ret;
352}
353
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354/**
355 * decode a frame.
356 * @param buf bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE larger then the actual read bytes
357 * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
358 * @param buf_size the size of the buffer in bytes
359 * @param got_picture_ptr zero if no frame could be decompressed, Otherwise, it is non zero
360 * @return -1 if error, otherwise return the number of
361 * bytes used.
362 */
492cd3a9 363int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
de6d9b64 364 int *got_picture_ptr,
0c1a9eda 365 uint8_t *buf, int buf_size)
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366{
367 int ret;
1e491e29 368
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369 ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
370 buf, buf_size);
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371
372 emms_c(); //needed to avoid a emms_c() call before every return;
1e491e29 373
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374 if (*got_picture_ptr)
375 avctx->frame_number++;
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376 return ret;
377}
378
379/* decode an audio frame. return -1 if error, otherwise return the
380 *number of bytes used. If no frame could be decompressed,
381 *frame_size_ptr is zero. Otherwise, it is the decompressed frame
382 *size in BYTES. */
0c1a9eda 383int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples,
de6d9b64 384 int *frame_size_ptr,
0c1a9eda 385 uint8_t *buf, int buf_size)
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386{
387 int ret;
388
389 ret = avctx->codec->decode(avctx, samples, frame_size_ptr,
390 buf, buf_size);
391 avctx->frame_number++;
392 return ret;
393}
394
395int avcodec_close(AVCodecContext *avctx)
396{
397 if (avctx->codec->close)
398 avctx->codec->close(avctx);
3123dd79 399 av_freep(&avctx->priv_data);
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400 avctx->codec = NULL;
401 return 0;
402}
403
404AVCodec *avcodec_find_encoder(enum CodecID id)
405{
406 AVCodec *p;
407 p = first_avcodec;
408 while (p) {
409 if (p->encode != NULL && p->id == id)
410 return p;
411 p = p->next;
412 }
413 return NULL;
414}
415
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416AVCodec *avcodec_find_encoder_by_name(const char *name)
417{
418 AVCodec *p;
419 p = first_avcodec;
420 while (p) {
421 if (p->encode != NULL && strcmp(name,p->name) == 0)
422 return p;
423 p = p->next;
424 }
425 return NULL;
426}
427
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428AVCodec *avcodec_find_decoder(enum CodecID id)
429{
430 AVCodec *p;
431 p = first_avcodec;
432 while (p) {
433 if (p->decode != NULL && p->id == id)
434 return p;
435 p = p->next;
436 }
437 return NULL;
438}
439
440AVCodec *avcodec_find_decoder_by_name(const char *name)
441{
442 AVCodec *p;
443 p = first_avcodec;
444 while (p) {
445 if (p->decode != NULL && strcmp(name,p->name) == 0)
446 return p;
447 p = p->next;
448 }
449 return NULL;
450}
451
452AVCodec *avcodec_find(enum CodecID id)
453{
454 AVCodec *p;
455 p = first_avcodec;
456 while (p) {
457 if (p->id == id)
458 return p;
459 p = p->next;
460 }
461 return NULL;
462}
463
464void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
465{
466 const char *codec_name;
467 AVCodec *p;
468 char buf1[32];
623563c0 469 char channels_str[100];
a96b68b7 470 int bitrate;
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471
472 if (encode)
473 p = avcodec_find_encoder(enc->codec_id);
474 else
475 p = avcodec_find_decoder(enc->codec_id);
476
477 if (p) {
478 codec_name = p->name;
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479 if (!encode && enc->codec_id == CODEC_ID_MP3) {
480 if (enc->sub_id == 2)
481 codec_name = "mp2";
482 else if (enc->sub_id == 1)
483 codec_name = "mp1";
484 }
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485 } else if (enc->codec_name[0] != '\0') {
486 codec_name = enc->codec_name;
487 } else {
488 /* output avi tags */
489 if (enc->codec_type == CODEC_TYPE_VIDEO) {
490 snprintf(buf1, sizeof(buf1), "%c%c%c%c",
491 enc->codec_tag & 0xff,
492 (enc->codec_tag >> 8) & 0xff,
493 (enc->codec_tag >> 16) & 0xff,
494 (enc->codec_tag >> 24) & 0xff);
495 } else {
496 snprintf(buf1, sizeof(buf1), "0x%04x", enc->codec_tag);
497 }
498 codec_name = buf1;
499 }
500
501 switch(enc->codec_type) {
502 case CODEC_TYPE_VIDEO:
503 snprintf(buf, buf_size,
504 "Video: %s%s",
7d1c3fc1 505 codec_name, enc->mb_decision ? " (hq)" : "");
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506 if (enc->codec_id == CODEC_ID_RAWVIDEO) {
507 snprintf(buf + strlen(buf), buf_size - strlen(buf),
508 ", %s",
9bbffbb1 509 avcodec_get_pix_fmt_name(enc->pix_fmt));
cf087595 510 }
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511 if (enc->width) {
512 snprintf(buf + strlen(buf), buf_size - strlen(buf),
513 ", %dx%d, %0.2f fps",
514 enc->width, enc->height,
14bea432 515 (float)enc->frame_rate / enc->frame_rate_base);
de6d9b64 516 }
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517 if (encode) {
518 snprintf(buf + strlen(buf), buf_size - strlen(buf),
519 ", q=%d-%d", enc->qmin, enc->qmax);
520 }
a96b68b7 521 bitrate = enc->bit_rate;
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522 break;
523 case CODEC_TYPE_AUDIO:
524 snprintf(buf, buf_size,
525 "Audio: %s",
526 codec_name);
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527 switch (enc->channels) {
528 case 1:
623563c0 529 strcpy(channels_str, "mono");
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530 break;
531 case 2:
623563c0 532 strcpy(channels_str, "stereo");
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533 break;
534 case 6:
623563c0 535 strcpy(channels_str, "5:1");
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536 break;
537 default:
538 sprintf(channels_str, "%d channels", enc->channels);
539 break;
540 }
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541 if (enc->sample_rate) {
542 snprintf(buf + strlen(buf), buf_size - strlen(buf),
543 ", %d Hz, %s",
544 enc->sample_rate,
e0d2714a 545 channels_str);
de6d9b64 546 }
e0d2714a 547
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548 /* for PCM codecs, compute bitrate directly */
549 switch(enc->codec_id) {
550 case CODEC_ID_PCM_S16LE:
551 case CODEC_ID_PCM_S16BE:
552 case CODEC_ID_PCM_U16LE:
553 case CODEC_ID_PCM_U16BE:
a190b7e9 554 bitrate = enc->sample_rate * enc->channels * 16;
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555 break;
556 case CODEC_ID_PCM_S8:
557 case CODEC_ID_PCM_U8:
558 case CODEC_ID_PCM_ALAW:
559 case CODEC_ID_PCM_MULAW:
a190b7e9 560 bitrate = enc->sample_rate * enc->channels * 8;
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561 break;
562 default:
563 bitrate = enc->bit_rate;
564 break;
565 }
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566 break;
567 default:
b71472eb 568 av_abort();
de6d9b64 569 }
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570 if (encode) {
571 if (enc->flags & CODEC_FLAG_PASS1)
572 snprintf(buf + strlen(buf), buf_size - strlen(buf),
573 ", pass 1");
574 if (enc->flags & CODEC_FLAG_PASS2)
575 snprintf(buf + strlen(buf), buf_size - strlen(buf),
576 ", pass 2");
577 }
a96b68b7 578 if (bitrate != 0) {
de6d9b64 579 snprintf(buf + strlen(buf), buf_size - strlen(buf),
a96b68b7 580 ", %d kb/s", bitrate / 1000);
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581 }
582}
583
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584unsigned avcodec_version( void )
585{
586 return LIBAVCODEC_VERSION_INT;
587}
cf087595 588
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589unsigned avcodec_build( void )
590{
591 return LIBAVCODEC_BUILD;
592}
593
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594/* must be called before any other functions */
595void avcodec_init(void)
596{
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597 static int inited = 0;
598
599 if (inited != 0)
600 return;
601 inited = 1;
602
59cf08ce 603 dsputil_static_init();
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604}
605
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606/**
607 * Flush buffers, should be called when seeking or when swicthing to a different stream.
608 */
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609void avcodec_flush_buffers(AVCodecContext *avctx)
610{
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611 if(avctx->codec->flush)
612 avctx->codec->flush(avctx);
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613}
614
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615void avcodec_default_free_buffers(AVCodecContext *s){
616 int i, j;
617
618 if(s->internal_buffer==NULL) return;
619
620 for(i=0; i<INTERNAL_BUFFER_SIZE; i++){
621 InternalBuffer *buf= &((InternalBuffer*)s->internal_buffer)[i];
622 for(j=0; j<4; j++){
623 av_freep(&buf->base[j]);
624 buf->data[j]= NULL;
625 }
626 }
627 av_freep(&s->internal_buffer);
628
629 s->internal_buffer_count=0;
630}
631
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632char av_get_pict_type_char(int pict_type){
633 switch(pict_type){
634 case I_TYPE: return 'I';
635 case P_TYPE: return 'P';
636 case B_TYPE: return 'B';
637 case S_TYPE: return 'S';
638 case SI_TYPE:return 'i';
639 case SP_TYPE:return 'p';
640 default: return '?';
641 }
642}
643
14bea432
MN
644int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max){
645 int exact=1, sign=0;
646 int64_t gcd, larger;
647
648 assert(den != 0);
649
650 if(den < 0){
651 den= -den;
652 nom= -nom;
653 }
654
655 if(nom < 0){
656 nom= -nom;
657 sign= 1;
658 }
659
660 for(;;){ //note is executed 1 or 2 times
661 gcd = ff_gcd(nom, den);
662 nom /= gcd;
663 den /= gcd;
664
665 larger= FFMAX(nom, den);
666
667 if(larger > max){
668 int64_t div= (larger + max - 1) / max;
669 nom = (nom + div/2)/div;
670 den = (den + div/2)/div;
671 exact=0;
672 }else
673 break;
674 }
675
676 if(sign) nom= -nom;
677
678 *dst_nom = nom;
679 *dst_den = den;
680
681 return exact;
682}
683
684int64_t av_rescale(int64_t a, int b, int c){
685 uint64_t h, l;
686 assert(c > 0);
687 assert(b >=0);
688
689 if(a<0) return -av_rescale(-a, b, c);
690
691 h= a>>32;
692 if(h==0) return a*b/c;
693
694 l= a&0xFFFFFFFF;
695 l *= b;
696 h *= b;
697
698 l += (h%c)<<32;
699
700 return ((h/c)<<32) + l/c;
701}