libmpeg2 style bitstream reader 17 vs 16 bit bugfix
[libav.git] / libavcodec / utils.c
CommitLineData
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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 */
87void av_free_static()
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);
160
161 switch(s->pix_fmt){
162 case PIX_FMT_YUV422:
163 pixel_size=2;
164 break;
165 case PIX_FMT_RGB24:
166 case PIX_FMT_BGR24:
167 pixel_size=3;
168 break;
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169 case PIX_FMT_RGBA32:
170 pixel_size=4;
171 break;
172 default:
173 pixel_size=1;
174 }
175
176 if(s->codec_id==CODEC_ID_SVQ1) align=63;
177 else align=15;
178
179 w= (width +align)&~align;
180 h= (height+align)&~align;
181
182 if(!(s->flags&CODEC_FLAG_EMU_EDGE)){
183 w+= EDGE_WIDTH*2;
184 h+= EDGE_WIDTH*2;
185 }
186
d90cf87b 187 buf->last_pic_num= -256*256*256*64;
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188
189 for(i=0; i<3; i++){
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190 const int h_shift= i==0 ? 0 : h_chroma_shift;
191 const int v_shift= i==0 ? 0 : v_chroma_shift;
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192
193 pic->linesize[i]= pixel_size*w>>h_shift;
194
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195 buf->base[i]= av_mallocz((pic->linesize[i]*h>>v_shift)+16); //FIXME 16
196 if(buf->base[i]==NULL) return -1;
197 memset(buf->base[i], 128, pic->linesize[i]*h>>v_shift);
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198
199 if(s->flags&CODEC_FLAG_EMU_EDGE)
d90cf87b 200 buf->data[i] = buf->base[i];
1e491e29 201 else
d90cf87b 202 buf->data[i] = buf->base[i] + (pic->linesize[i]*EDGE_WIDTH>>v_shift) + (EDGE_WIDTH>>h_shift);
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203 }
204 pic->age= 256*256*256*64;
4e00e76b 205 pic->type= FF_BUFFER_TYPE_INTERNAL;
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206 }
207
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208 for(i=0; i<4; i++){
209 pic->base[i]= buf->base[i];
210 pic->data[i]= buf->data[i];
211 }
212 s->internal_buffer_count++;
213
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214 return 0;
215}
216
492cd3a9 217void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
1e491e29 218 int i;
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219 InternalBuffer *buf, *last, temp;
220
4e00e76b 221 assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
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222
223 for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
224 buf= &((InternalBuffer*)s->internal_buffer)[i];
225 if(buf->data[0] == pic->data[0])
226 break;
227 }
228 assert(i < s->internal_buffer_count);
229 s->internal_buffer_count--;
230 last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
231
232 temp= *buf;
233 *buf= *last;
234 *last= temp;
235
236 for(i=0; i<3; i++){
1e491e29 237 pic->data[i]=NULL;
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238// pic->base[i]=NULL;
239 }
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240//printf("R%X\n", pic->opaque);
241}
242
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243enum PixelFormat avcodec_default_get_format(struct AVCodecContext *s, enum PixelFormat * fmt){
244 return fmt[0];
245}
246
a949d72e 247void avcodec_get_context_defaults(AVCodecContext *s){
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248 s->bit_rate= 800*1000;
249 s->bit_rate_tolerance= s->bit_rate*10;
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250 s->qmin= 2;
251 s->qmax= 31;
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252 s->mb_qmin= 2;
253 s->mb_qmax= 31;
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254 s->rc_eq= "tex^qComp";
255 s->qcompress= 0.5;
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256 s->max_qdiff= 3;
257 s->b_quant_factor=1.25;
258 s->b_quant_offset=1.25;
b3a391e8 259 s->i_quant_factor=-0.8;
e8b62df6 260 s->i_quant_offset=0.0;
4d2858de 261 s->error_concealment= 3;
8d0e42ca 262 s->error_resilience= 1;
4d2858de 263 s->workaround_bugs= FF_BUG_AUTODETECT;
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264 s->frame_rate_base= 1;
265 s->frame_rate = 25;
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266 s->gop_size= 50;
267 s->me_method= ME_EPZS;
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268 s->get_buffer= avcodec_default_get_buffer;
269 s->release_buffer= avcodec_default_release_buffer;
a33c7159 270 s->get_format= avcodec_default_get_format;
826f429a 271 s->me_subpel_quality=8;
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272
273 s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
274 s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;
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275}
276
277/**
278 * allocates a AVCodecContext and set it to defaults.
279 * this can be deallocated by simply calling free()
280 */
7ffbb60e 281AVCodecContext *avcodec_alloc_context(void){
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282 AVCodecContext *avctx= av_mallocz(sizeof(AVCodecContext));
283
284 if(avctx==NULL) return NULL;
285
286 avcodec_get_context_defaults(avctx);
287
288 return avctx;
289}
290
1e491e29 291/**
492cd3a9 292 * allocates a AVPFrame and set it to defaults.
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293 * this can be deallocated by simply calling free()
294 */
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295AVFrame *avcodec_alloc_frame(void){
296 AVFrame *pic= av_mallocz(sizeof(AVFrame));
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297
298 return pic;
299}
300
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301int avcodec_open(AVCodecContext *avctx, AVCodec *codec)
302{
303 int ret;
304
305 avctx->codec = codec;
4cb3ca72 306 avctx->codec_id = codec->id;
de6d9b64 307 avctx->frame_number = 0;
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308 if (codec->priv_data_size > 0) {
309 avctx->priv_data = av_mallocz(codec->priv_data_size);
310 if (!avctx->priv_data)
311 return -ENOMEM;
312 } else {
313 avctx->priv_data = NULL;
314 }
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315 ret = avctx->codec->init(avctx);
316 if (ret < 0) {
3123dd79 317 av_freep(&avctx->priv_data);
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318 return ret;
319 }
320 return 0;
321}
322
0c1a9eda 323int avcodec_encode_audio(AVCodecContext *avctx, uint8_t *buf, int buf_size,
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324 const short *samples)
325{
326 int ret;
327
328 ret = avctx->codec->encode(avctx, buf, buf_size, (void *)samples);
329 avctx->frame_number++;
330 return ret;
331}
332
0c1a9eda 333int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
492cd3a9 334 const AVFrame *pict)
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335{
336 int ret;
337
338 ret = avctx->codec->encode(avctx, buf, buf_size, (void *)pict);
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339
340 emms_c(); //needed to avoid a emms_c() call before every return;
341
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342 avctx->frame_number++;
343 return ret;
344}
345
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346/**
347 * decode a frame.
348 * @param buf bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE larger then the actual read bytes
349 * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
350 * @param buf_size the size of the buffer in bytes
351 * @param got_picture_ptr zero if no frame could be decompressed, Otherwise, it is non zero
352 * @return -1 if error, otherwise return the number of
353 * bytes used.
354 */
492cd3a9 355int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
de6d9b64 356 int *got_picture_ptr,
0c1a9eda 357 uint8_t *buf, int buf_size)
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358{
359 int ret;
1e491e29 360
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361 ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
362 buf, buf_size);
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363
364 emms_c(); //needed to avoid a emms_c() call before every return;
1e491e29 365
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366 if (*got_picture_ptr)
367 avctx->frame_number++;
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368 return ret;
369}
370
371/* decode an audio frame. return -1 if error, otherwise return the
372 *number of bytes used. If no frame could be decompressed,
373 *frame_size_ptr is zero. Otherwise, it is the decompressed frame
374 *size in BYTES. */
0c1a9eda 375int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples,
de6d9b64 376 int *frame_size_ptr,
0c1a9eda 377 uint8_t *buf, int buf_size)
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378{
379 int ret;
380
381 ret = avctx->codec->decode(avctx, samples, frame_size_ptr,
382 buf, buf_size);
383 avctx->frame_number++;
384 return ret;
385}
386
387int avcodec_close(AVCodecContext *avctx)
388{
389 if (avctx->codec->close)
390 avctx->codec->close(avctx);
3123dd79 391 av_freep(&avctx->priv_data);
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392 avctx->codec = NULL;
393 return 0;
394}
395
396AVCodec *avcodec_find_encoder(enum CodecID id)
397{
398 AVCodec *p;
399 p = first_avcodec;
400 while (p) {
401 if (p->encode != NULL && p->id == id)
402 return p;
403 p = p->next;
404 }
405 return NULL;
406}
407
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408AVCodec *avcodec_find_encoder_by_name(const char *name)
409{
410 AVCodec *p;
411 p = first_avcodec;
412 while (p) {
413 if (p->encode != NULL && strcmp(name,p->name) == 0)
414 return p;
415 p = p->next;
416 }
417 return NULL;
418}
419
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420AVCodec *avcodec_find_decoder(enum CodecID id)
421{
422 AVCodec *p;
423 p = first_avcodec;
424 while (p) {
425 if (p->decode != NULL && p->id == id)
426 return p;
427 p = p->next;
428 }
429 return NULL;
430}
431
432AVCodec *avcodec_find_decoder_by_name(const char *name)
433{
434 AVCodec *p;
435 p = first_avcodec;
436 while (p) {
437 if (p->decode != NULL && strcmp(name,p->name) == 0)
438 return p;
439 p = p->next;
440 }
441 return NULL;
442}
443
444AVCodec *avcodec_find(enum CodecID id)
445{
446 AVCodec *p;
447 p = first_avcodec;
448 while (p) {
449 if (p->id == id)
450 return p;
451 p = p->next;
452 }
453 return NULL;
454}
455
456void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
457{
458 const char *codec_name;
459 AVCodec *p;
460 char buf1[32];
623563c0 461 char channels_str[100];
a96b68b7 462 int bitrate;
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463
464 if (encode)
465 p = avcodec_find_encoder(enc->codec_id);
466 else
467 p = avcodec_find_decoder(enc->codec_id);
468
469 if (p) {
470 codec_name = p->name;
471 } else if (enc->codec_name[0] != '\0') {
472 codec_name = enc->codec_name;
473 } else {
474 /* output avi tags */
475 if (enc->codec_type == CODEC_TYPE_VIDEO) {
476 snprintf(buf1, sizeof(buf1), "%c%c%c%c",
477 enc->codec_tag & 0xff,
478 (enc->codec_tag >> 8) & 0xff,
479 (enc->codec_tag >> 16) & 0xff,
480 (enc->codec_tag >> 24) & 0xff);
481 } else {
482 snprintf(buf1, sizeof(buf1), "0x%04x", enc->codec_tag);
483 }
484 codec_name = buf1;
485 }
486
487 switch(enc->codec_type) {
488 case CODEC_TYPE_VIDEO:
489 snprintf(buf, buf_size,
490 "Video: %s%s",
491 codec_name, enc->flags & CODEC_FLAG_HQ ? " (hq)" : "");
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492 if (enc->codec_id == CODEC_ID_RAWVIDEO) {
493 snprintf(buf + strlen(buf), buf_size - strlen(buf),
494 ", %s",
9bbffbb1 495 avcodec_get_pix_fmt_name(enc->pix_fmt));
cf087595 496 }
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497 if (enc->width) {
498 snprintf(buf + strlen(buf), buf_size - strlen(buf),
499 ", %dx%d, %0.2f fps",
500 enc->width, enc->height,
14bea432 501 (float)enc->frame_rate / enc->frame_rate_base);
de6d9b64 502 }
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503 if (encode) {
504 snprintf(buf + strlen(buf), buf_size - strlen(buf),
505 ", q=%d-%d", enc->qmin, enc->qmax);
506 }
a96b68b7 507 bitrate = enc->bit_rate;
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508 break;
509 case CODEC_TYPE_AUDIO:
510 snprintf(buf, buf_size,
511 "Audio: %s",
512 codec_name);
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513 switch (enc->channels) {
514 case 1:
623563c0 515 strcpy(channels_str, "mono");
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516 break;
517 case 2:
623563c0 518 strcpy(channels_str, "stereo");
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519 break;
520 case 6:
623563c0 521 strcpy(channels_str, "5:1");
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522 break;
523 default:
524 sprintf(channels_str, "%d channels", enc->channels);
525 break;
526 }
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527 if (enc->sample_rate) {
528 snprintf(buf + strlen(buf), buf_size - strlen(buf),
529 ", %d Hz, %s",
530 enc->sample_rate,
e0d2714a 531 channels_str);
de6d9b64 532 }
e0d2714a 533
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534 /* for PCM codecs, compute bitrate directly */
535 switch(enc->codec_id) {
536 case CODEC_ID_PCM_S16LE:
537 case CODEC_ID_PCM_S16BE:
538 case CODEC_ID_PCM_U16LE:
539 case CODEC_ID_PCM_U16BE:
a190b7e9 540 bitrate = enc->sample_rate * enc->channels * 16;
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541 break;
542 case CODEC_ID_PCM_S8:
543 case CODEC_ID_PCM_U8:
544 case CODEC_ID_PCM_ALAW:
545 case CODEC_ID_PCM_MULAW:
a190b7e9 546 bitrate = enc->sample_rate * enc->channels * 8;
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547 break;
548 default:
549 bitrate = enc->bit_rate;
550 break;
551 }
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552 break;
553 default:
b71472eb 554 av_abort();
de6d9b64 555 }
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556 if (encode) {
557 if (enc->flags & CODEC_FLAG_PASS1)
558 snprintf(buf + strlen(buf), buf_size - strlen(buf),
559 ", pass 1");
560 if (enc->flags & CODEC_FLAG_PASS2)
561 snprintf(buf + strlen(buf), buf_size - strlen(buf),
562 ", pass 2");
563 }
a96b68b7 564 if (bitrate != 0) {
de6d9b64 565 snprintf(buf + strlen(buf), buf_size - strlen(buf),
a96b68b7 566 ", %d kb/s", bitrate / 1000);
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567 }
568}
569
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570unsigned avcodec_version( void )
571{
572 return LIBAVCODEC_VERSION_INT;
573}
cf087595 574
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575unsigned avcodec_build( void )
576{
577 return LIBAVCODEC_BUILD;
578}
579
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580/* must be called before any other functions */
581void avcodec_init(void)
582{
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583 static int inited = 0;
584
585 if (inited != 0)
586 return;
587 inited = 1;
588
59cf08ce 589 dsputil_static_init();
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590}
591
4e00e76b 592/* this can be called after seeking and before trying to decode the next keyframe */
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593void avcodec_flush_buffers(AVCodecContext *avctx)
594{
4e00e76b 595 int i;
1c2a8c7f 596 MpegEncContext *s = avctx->priv_data;
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597
598 switch(avctx->codec_id){
599 case CODEC_ID_MPEG1VIDEO:
600 case CODEC_ID_H263:
601 case CODEC_ID_RV10:
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602// case CODEC_ID_MJPEG:
603// case CODEC_ID_MJPEGB:
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604 case CODEC_ID_MPEG4:
605 case CODEC_ID_MSMPEG4V1:
606 case CODEC_ID_MSMPEG4V2:
607 case CODEC_ID_MSMPEG4V3:
608 case CODEC_ID_WMV1:
609 case CODEC_ID_WMV2:
610 case CODEC_ID_H263P:
611 case CODEC_ID_H263I:
612 case CODEC_ID_SVQ1:
613 for(i=0; i<MAX_PICTURE_COUNT; i++){
614 if(s->picture[i].data[0] && ( s->picture[i].type == FF_BUFFER_TYPE_INTERNAL
615 || s->picture[i].type == FF_BUFFER_TYPE_USER))
492cd3a9 616 avctx->release_buffer(avctx, (AVFrame*)&s->picture[i]);
87fb268f 617 }
b536d0aa 618 s->last_picture_ptr = s->next_picture_ptr = NULL;
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619 break;
620 default:
621 //FIXME
622 break;
623 }
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624}
625
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626void avcodec_default_free_buffers(AVCodecContext *s){
627 int i, j;
628
629 if(s->internal_buffer==NULL) return;
630
631 for(i=0; i<INTERNAL_BUFFER_SIZE; i++){
632 InternalBuffer *buf= &((InternalBuffer*)s->internal_buffer)[i];
633 for(j=0; j<4; j++){
634 av_freep(&buf->base[j]);
635 buf->data[j]= NULL;
636 }
637 }
638 av_freep(&s->internal_buffer);
639
640 s->internal_buffer_count=0;
641}
642
14bea432
MN
643int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max){
644 int exact=1, sign=0;
645 int64_t gcd, larger;
646
647 assert(den != 0);
648
649 if(den < 0){
650 den= -den;
651 nom= -nom;
652 }
653
654 if(nom < 0){
655 nom= -nom;
656 sign= 1;
657 }
658
659 for(;;){ //note is executed 1 or 2 times
660 gcd = ff_gcd(nom, den);
661 nom /= gcd;
662 den /= gcd;
663
664 larger= FFMAX(nom, den);
665
666 if(larger > max){
667 int64_t div= (larger + max - 1) / max;
668 nom = (nom + div/2)/div;
669 den = (den + div/2)/div;
670 exact=0;
671 }else
672 break;
673 }
674
675 if(sign) nom= -nom;
676
677 *dst_nom = nom;
678 *dst_den = den;
679
680 return exact;
681}
682
683int64_t av_rescale(int64_t a, int b, int c){
684 uint64_t h, l;
685 assert(c > 0);
686 assert(b >=0);
687
688 if(a<0) return -av_rescale(-a, b, c);
689
690 h= a>>32;
691 if(h==0) return a*b/c;
692
693 l= a&0xFFFFFFFF;
694 l *= b;
695 h *= b;
696
697 l += (h%c)<<32;
698
699 return ((h/c)<<32) + l/c;
700}