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| 1 | /* | ||
| 2 | * copyright (c) 2001 Fabrice Bellard | ||
| 3 | * | ||
| 4 | * This file is part of FFmpeg. | ||
| 5 | * | ||
| 6 | * FFmpeg is free software; you can redistribute it and/or | ||
| 7 | * modify it under the terms of the GNU Lesser General Public | ||
| 8 | * License as published by the Free Software Foundation; either | ||
| 9 | * version 2.1 of the License, or (at your option) any later version. | ||
| 10 | * | ||
| 11 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 14 | * Lesser General Public License for more details. | ||
| 15 | * | ||
| 16 | * You should have received a copy of the GNU Lesser General Public | ||
| 17 | * License along with FFmpeg; if not, write to the Free Software | ||
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 19 | */ | ||
| 20 | |||
| 21 | /** | ||
| 22 | * @file libavcodec/apiexample.c | ||
| 23 | * avcodec API use example. | ||
| 24 | * | ||
| 25 | * Note that this library only handles codecs (mpeg, mpeg4, etc...), | ||
| 26 | * not file formats (avi, vob, etc...). See library 'libavformat' for the | ||
| 27 | * format handling | ||
| 28 | */ | ||
| 29 | |||
| 30 | #include <stdlib.h> | ||
| 31 | #include <stdio.h> | ||
| 32 | #include <string.h> | ||
| 33 | |||
| 34 | #ifdef HAVE_AV_CONFIG_H | ||
| 35 | #undef HAVE_AV_CONFIG_H | ||
| 36 | #endif | ||
| 37 | |||
| 38 | #include "avcodec.h" | ||
| 39 | #include "libavutil/mathematics.h" | ||
| 40 | |||
| 41 | #define INBUF_SIZE 4096 | ||
| 42 | |||
| 43 | /* | ||
| 44 | * Audio encoding example | ||
| 45 | */ | ||
| 46 | void audio_encode_example(const char *filename) | ||
| 47 | { | ||
| 48 | AVCodec *codec; | ||
| 49 | AVCodecContext *c= NULL; | ||
| 50 | int frame_size, i, j, out_size, outbuf_size; | ||
| 51 | FILE *f; | ||
| 52 | short *samples; | ||
| 53 | float t, tincr; | ||
| 54 | uint8_t *outbuf; | ||
| 55 | |||
| 56 | printf("Audio encoding\n"); | ||
| 57 | |||
| 58 | /* find the MP2 encoder */ | ||
| 59 | codec = avcodec_find_encoder(CODEC_ID_MP2); | ||
| 60 | if (!codec) { | ||
| 61 | fprintf(stderr, "codec not found\n"); | ||
| 62 | exit(1); | ||
| 63 | } | ||
| 64 | |||
| 65 | c= avcodec_alloc_context(); | ||
| 66 | |||
| 67 | /* put sample parameters */ | ||
| 68 | c->bit_rate = 64000; | ||
| 69 | c->sample_rate = 44100; | ||
| 70 | c->channels = 2; | ||
| 71 | |||
| 72 | /* open it */ | ||
| 73 | if (avcodec_open(c, codec) < 0) { | ||
| 74 | fprintf(stderr, "could not open codec\n"); | ||
| 75 | exit(1); | ||
| 76 | } | ||
| 77 | |||
| 78 | /* the codec gives us the frame size, in samples */ | ||
| 79 | frame_size = c->frame_size; | ||
| 80 | samples = malloc(frame_size * 2 * c->channels); | ||
| 81 | outbuf_size = 10000; | ||
| 82 | outbuf = malloc(outbuf_size); | ||
| 83 | |||
| 84 | f = fopen(filename, "wb"); | ||
| 85 | if (!f) { | ||
| 86 | fprintf(stderr, "could not open %s\n", filename); | ||
| 87 | exit(1); | ||
| 88 | } | ||
| 89 | |||
| 90 | /* encode a single tone sound */ | ||
| 91 | t = 0; | ||
| 92 | tincr = 2 * M_PI * 440.0 / c->sample_rate; | ||
| 93 | for(i=0;i<200;i++) { | ||
| 94 | for(j=0;j<frame_size;j++) { | ||
| 95 | samples[2*j] = (int)(sin(t) * 10000); | ||
| 96 | samples[2*j+1] = samples[2*j]; | ||
| 97 | t += tincr; | ||
| 98 | } | ||
| 99 | /* encode the samples */ | ||
| 100 | out_size = avcodec_encode_audio(c, outbuf, outbuf_size, samples); | ||
| 101 | fwrite(outbuf, 1, out_size, f); | ||
| 102 | } | ||
| 103 | fclose(f); | ||
| 104 | free(outbuf); | ||
| 105 | free(samples); | ||
| 106 | |||
| 107 | avcodec_close(c); | ||
| 108 | av_free(c); | ||
| 109 | } | ||
| 110 | |||
| 111 | /* | ||
| 112 | * Audio decoding. | ||
| 113 | */ | ||
| 114 | void audio_decode_example(const char *outfilename, const char *filename) | ||
| 115 | { | ||
| 116 | AVCodec *codec; | ||
| 117 | AVCodecContext *c= NULL; | ||
| 118 | int out_size, size, len; | ||
| 119 | FILE *f, *outfile; | ||
| 120 | uint8_t *outbuf; | ||
| 121 | uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE], *inbuf_ptr; | ||
| 122 | |||
| 123 | printf("Audio decoding\n"); | ||
| 124 | |||
| 125 | /* find the mpeg audio decoder */ | ||
| 126 | codec = avcodec_find_decoder(CODEC_ID_MP2); | ||
| 127 | if (!codec) { | ||
| 128 | fprintf(stderr, "codec not found\n"); | ||
| 129 | exit(1); | ||
| 130 | } | ||
| 131 | |||
| 132 | c= avcodec_alloc_context(); | ||
| 133 | |||
| 134 | /* open it */ | ||
| 135 | if (avcodec_open(c, codec) < 0) { | ||
| 136 | fprintf(stderr, "could not open codec\n"); | ||
| 137 | exit(1); | ||
| 138 | } | ||
| 139 | |||
| 140 | outbuf = malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE); | ||
| 141 | |||
| 142 | f = fopen(filename, "rb"); | ||
| 143 | if (!f) { | ||
| 144 | fprintf(stderr, "could not open %s\n", filename); | ||
| 145 | exit(1); | ||
| 146 | } | ||
| 147 | outfile = fopen(outfilename, "wb"); | ||
| 148 | if (!outfile) { | ||
| 149 | av_free(c); | ||
| 150 | exit(1); | ||
| 151 | } | ||
| 152 | |||
| 153 | /* decode until eof */ | ||
| 154 | inbuf_ptr = inbuf; | ||
| 155 | for(;;) { | ||
| 156 | size = fread(inbuf, 1, INBUF_SIZE, f); | ||
| 157 | if (size == 0) | ||
| 158 | break; | ||
| 159 | |||
| 160 | inbuf_ptr = inbuf; | ||
| 161 | while (size > 0) { | ||
| 162 | out_size = AVCODEC_MAX_AUDIO_FRAME_SIZE; | ||
| 163 | len = avcodec_decode_audio2(c, (short *)outbuf, &out_size, | ||
| 164 | inbuf_ptr, size); | ||
| 165 | if (len < 0) { | ||
| 166 | fprintf(stderr, "Error while decoding\n"); | ||
| 167 | exit(1); | ||
| 168 | } | ||
| 169 | if (out_size > 0) { | ||
| 170 | /* if a frame has been decoded, output it */ | ||
| 171 | fwrite(outbuf, 1, out_size, outfile); | ||
| 172 | } | ||
| 173 | size -= len; | ||
| 174 | inbuf_ptr += len; | ||
| 175 | } | ||
| 176 | } | ||
| 177 | |||
| 178 | fclose(outfile); | ||
| 179 | fclose(f); | ||
| 180 | free(outbuf); | ||
| 181 | |||
| 182 | avcodec_close(c); | ||
| 183 | av_free(c); | ||
| 184 | } | ||
| 185 | |||
| 186 | /* | ||
| 187 | * Video encoding example | ||
| 188 | */ | ||
| 189 | void video_encode_example(const char *filename) | ||
| 190 | { | ||
| 191 | AVCodec *codec; | ||
| 192 | AVCodecContext *c= NULL; | ||
| 193 | int i, out_size, size, x, y, outbuf_size; | ||
| 194 | FILE *f; | ||
| 195 | AVFrame *picture; | ||
| 196 | uint8_t *outbuf, *picture_buf; | ||
| 197 | |||
| 198 | printf("Video encoding\n"); | ||
| 199 | |||
| 200 | /* find the mpeg1 video encoder */ | ||
| 201 | codec = avcodec_find_encoder(CODEC_ID_MPEG1VIDEO); | ||
| 202 | if (!codec) { | ||
| 203 | fprintf(stderr, "codec not found\n"); | ||
| 204 | exit(1); | ||
| 205 | } | ||
| 206 | |||
| 207 | c= avcodec_alloc_context(); | ||
| 208 | picture= avcodec_alloc_frame(); | ||
| 209 | |||
| 210 | /* put sample parameters */ | ||
| 211 | c->bit_rate = 400000; | ||
| 212 | /* resolution must be a multiple of two */ | ||
| 213 | c->width = 352; | ||
| 214 | c->height = 288; | ||
| 215 | /* frames per second */ | ||
| 216 | c->time_base= (AVRational){1,25}; | ||
| 217 | c->gop_size = 10; /* emit one intra frame every ten frames */ | ||
| 218 | c->max_b_frames=1; | ||
| 219 | c->pix_fmt = PIX_FMT_YUV420P; | ||
| 220 | |||
| 221 | /* open it */ | ||
| 222 | if (avcodec_open(c, codec) < 0) { | ||
| 223 | fprintf(stderr, "could not open codec\n"); | ||
| 224 | exit(1); | ||
| 225 | } | ||
| 226 | |||
| 227 | f = fopen(filename, "wb"); | ||
| 228 | if (!f) { | ||
| 229 | fprintf(stderr, "could not open %s\n", filename); | ||
| 230 | exit(1); | ||
| 231 | } | ||
| 232 | |||
| 233 | /* alloc image and output buffer */ | ||
| 234 | outbuf_size = 100000; | ||
| 235 | outbuf = malloc(outbuf_size); | ||
| 236 | size = c->width * c->height; | ||
| 237 | picture_buf = malloc((size * 3) / 2); /* size for YUV 420 */ | ||
| 238 | |||
| 239 | picture->data[0] = picture_buf; | ||
| 240 | picture->data[1] = picture->data[0] + size; | ||
| 241 | picture->data[2] = picture->data[1] + size / 4; | ||
| 242 | picture->linesize[0] = c->width; | ||
| 243 | picture->linesize[1] = c->width / 2; | ||
| 244 | picture->linesize[2] = c->width / 2; | ||
| 245 | |||
| 246 | /* encode 1 second of video */ | ||
| 247 | for(i=0;i<25;i++) { | ||
| 248 | fflush(stdout); | ||
| 249 | /* prepare a dummy image */ | ||
| 250 | /* Y */ | ||
| 251 | for(y=0;y<c->height;y++) { | ||
| 252 | for(x=0;x<c->width;x++) { | ||
| 253 | picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3; | ||
| 254 | } | ||
| 255 | } | ||
| 256 | |||
| 257 | /* Cb and Cr */ | ||
| 258 | for(y=0;y<c->height/2;y++) { | ||
| 259 | for(x=0;x<c->width/2;x++) { | ||
| 260 | picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2; | ||
| 261 | picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5; | ||
| 262 | } | ||
| 263 | } | ||
| 264 | |||
| 265 | /* encode the image */ | ||
| 266 | out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture); | ||
| 267 | printf("encoding frame %3d (size=%5d)\n", i, out_size); | ||
| 268 | fwrite(outbuf, 1, out_size, f); | ||
| 269 | } | ||
| 270 | |||
| 271 | /* get the delayed frames */ | ||
| 272 | for(; out_size; i++) { | ||
| 273 | fflush(stdout); | ||
| 274 | |||
| 275 | out_size = avcodec_encode_video(c, outbuf, outbuf_size, NULL); | ||
| 276 | printf("write frame %3d (size=%5d)\n", i, out_size); | ||
| 277 | fwrite(outbuf, 1, out_size, f); | ||
| 278 | } | ||
| 279 | |||
| 280 | /* add sequence end code to have a real mpeg file */ | ||
| 281 | outbuf[0] = 0x00; | ||
| 282 | outbuf[1] = 0x00; | ||
| 283 | outbuf[2] = 0x01; | ||
| 284 | outbuf[3] = 0xb7; | ||
| 285 | fwrite(outbuf, 1, 4, f); | ||
| 286 | fclose(f); | ||
| 287 | free(picture_buf); | ||
| 288 | free(outbuf); | ||
| 289 | |||
| 290 | avcodec_close(c); | ||
| 291 | av_free(c); | ||
| 292 | av_free(picture); | ||
| 293 | printf("\n"); | ||
| 294 | } | ||
| 295 | |||
| 296 | /* | ||
| 297 | * Video decoding example | ||
| 298 | */ | ||
| 299 | |||
| 300 | void pgm_save(unsigned char *buf,int wrap, int xsize,int ysize,char *filename) | ||
| 301 | { | ||
| 302 | FILE *f; | ||
| 303 | int i; | ||
| 304 | |||
| 305 | f=fopen(filename,"w"); | ||
| 306 | fprintf(f,"P5\n%d %d\n%d\n",xsize,ysize,255); | ||
| 307 | for(i=0;i<ysize;i++) | ||
| 308 | fwrite(buf + i * wrap,1,xsize,f); | ||
| 309 | fclose(f); | ||
| 310 | } | ||
| 311 | |||
| 312 | void video_decode_example(const char *outfilename, const char *filename) | ||
| 313 | { | ||
| 314 | AVCodec *codec; | ||
| 315 | AVCodecContext *c= NULL; | ||
| 316 | int frame, size, got_picture, len; | ||
| 317 | FILE *f; | ||
| 318 | AVFrame *picture; | ||
| 319 | uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE], *inbuf_ptr; | ||
| 320 | char buf[1024]; | ||
| 321 | |||
| 322 | /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ | ||
| 323 | memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); | ||
| 324 | |||
| 325 | printf("Video decoding\n"); | ||
| 326 | |||
| 327 | /* find the mpeg1 video decoder */ | ||
| 328 | codec = avcodec_find_decoder(CODEC_ID_MPEG1VIDEO); | ||
| 329 | if (!codec) { | ||
| 330 | fprintf(stderr, "codec not found\n"); | ||
| 331 | exit(1); | ||
| 332 | } | ||
| 333 | |||
| 334 | c= avcodec_alloc_context(); | ||
| 335 | picture= avcodec_alloc_frame(); | ||
| 336 | |||
| 337 | if(codec->capabilities&CODEC_CAP_TRUNCATED) | ||
| 338 | c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ | ||
| 339 | |||
| 340 | /* For some codecs, such as msmpeg4 and mpeg4, width and height | ||
| 341 | MUST be initialized there because this information is not | ||
| 342 | available in the bitstream. */ | ||
| 343 | |||
| 344 | /* open it */ | ||
| 345 | if (avcodec_open(c, codec) < 0) { | ||
| 346 | fprintf(stderr, "could not open codec\n"); | ||
| 347 | exit(1); | ||
| 348 | } | ||
| 349 | |||
| 350 | /* the codec gives us the frame size, in samples */ | ||
| 351 | |||
| 352 | f = fopen(filename, "rb"); | ||
| 353 | if (!f) { | ||
| 354 | fprintf(stderr, "could not open %s\n", filename); | ||
| 355 | exit(1); | ||
| 356 | } | ||
| 357 | |||
| 358 | frame = 0; | ||
| 359 | for(;;) { | ||
| 360 | size = fread(inbuf, 1, INBUF_SIZE, f); | ||
| 361 | if (size == 0) | ||
| 362 | break; | ||
| 363 | |||
| 364 | /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) | ||
| 365 | and this is the only method to use them because you cannot | ||
| 366 | know the compressed data size before analysing it. | ||
| 367 | |||
| 368 | BUT some other codecs (msmpeg4, mpeg4) are inherently frame | ||
| 369 | based, so you must call them with all the data for one | ||
| 370 | frame exactly. You must also initialize 'width' and | ||
| 371 | 'height' before initializing them. */ | ||
| 372 | |||
| 373 | /* NOTE2: some codecs allow the raw parameters (frame size, | ||
| 374 | sample rate) to be changed at any frame. We handle this, so | ||
| 375 | you should also take care of it */ | ||
| 376 | |||
| 377 | /* here, we use a stream based decoder (mpeg1video), so we | ||
| 378 | feed decoder and see if it could decode a frame */ | ||
| 379 | inbuf_ptr = inbuf; | ||
| 380 | while (size > 0) { | ||
| 381 | len = avcodec_decode_video(c, picture, &got_picture, | ||
| 382 | inbuf_ptr, size); | ||
| 383 | if (len < 0) { | ||
| 384 | fprintf(stderr, "Error while decoding frame %d\n", frame); | ||
| 385 | exit(1); | ||
| 386 | } | ||
| 387 | if (got_picture) { | ||
| 388 | printf("saving frame %3d\n", frame); | ||
| 389 | fflush(stdout); | ||
| 390 | |||
| 391 | /* the picture is allocated by the decoder. no need to | ||
| 392 | free it */ | ||
| 393 | snprintf(buf, sizeof(buf), outfilename, frame); | ||
| 394 | pgm_save(picture->data[0], picture->linesize[0], | ||
| 395 | c->width, c->height, buf); | ||
| 396 | frame++; | ||
| 397 | } | ||
| 398 | size -= len; | ||
| 399 | inbuf_ptr += len; | ||
| 400 | } | ||
| 401 | } | ||
| 402 | |||
| 403 | /* some codecs, such as MPEG, transmit the I and P frame with a | ||
| 404 | latency of one frame. You must do the following to have a | ||
| 405 | chance to get the last frame of the video */ | ||
| 406 | len = avcodec_decode_video(c, picture, &got_picture, | ||
| 407 | NULL, 0); | ||
| 408 | if (got_picture) { | ||
| 409 | printf("saving last frame %3d\n", frame); | ||
| 410 | fflush(stdout); | ||
| 411 | |||
| 412 | /* the picture is allocated by the decoder. no need to | ||
| 413 | free it */ | ||
| 414 | snprintf(buf, sizeof(buf), outfilename, frame); | ||
| 415 | pgm_save(picture->data[0], picture->linesize[0], | ||
| 416 | c->width, c->height, buf); | ||
| 417 | frame++; | ||
| 418 | } | ||
| 419 | |||
| 420 | fclose(f); | ||
| 421 | |||
| 422 | avcodec_close(c); | ||
| 423 | av_free(c); | ||
| 424 | av_free(picture); | ||
| 425 | printf("\n"); | ||
| 426 | } | ||
| 427 | |||
| 428 | int main(int argc, char **argv) | ||
| 429 | { | ||
| 430 | const char *filename; | ||
| 431 | |||
| 432 | /* must be called before using avcodec lib */ | ||
| 433 | avcodec_init(); | ||
| 434 | |||
| 435 | /* register all the codecs */ | ||
| 436 | avcodec_register_all(); | ||
| 437 | |||
| 438 | if (argc <= 1) { | ||
| 439 | audio_encode_example("/tmp/test.mp2"); | ||
| 440 | audio_decode_example("/tmp/test.sw", "/tmp/test.mp2"); | ||
| 441 | |||
| 442 | video_encode_example("/tmp/test.mpg"); | ||
| 443 | filename = "/tmp/test.mpg"; | ||
| 444 | } else { | ||
| 445 | filename = argv[1]; | ||
| 446 | } | ||
| 447 | |||
| 448 | // audio_decode_example("/tmp/test.sw", filename); | ||
| 449 | video_decode_example("/tmp/test%d.pgm", filename); | ||
| 450 | |||
| 451 | return 0; | ||
| 452 | } | ||