| 1 | /* |
| 2 | * Copyright (c) 2001 Fabrice Bellard |
| 3 | * |
| 4 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 5 | * of this software and associated documentation files (the "Software"), to deal |
| 6 | * in the Software without restriction, including without limitation the rights |
| 7 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 8 | * copies of the Software, and to permit persons to whom the Software is |
| 9 | * furnished to do so, subject to the following conditions: |
| 10 | * |
| 11 | * The above copyright notice and this permission notice shall be included in |
| 12 | * all copies or substantial portions of the Software. |
| 13 | * |
| 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 15 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 17 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 18 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 19 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 20 | * THE SOFTWARE. |
| 21 | */ |
| 22 | |
| 23 | /** |
| 24 | * @file |
| 25 | * libavcodec API use example. |
| 26 | * |
| 27 | * @example decoding_encoding.c |
| 28 | * Note that libavcodec only handles codecs (mpeg, mpeg4, etc...), |
| 29 | * not file formats (avi, vob, mp4, mov, mkv, mxf, flv, mpegts, mpegps, etc...). See library 'libavformat' for the |
| 30 | * format handling |
| 31 | */ |
| 32 | |
| 33 | #include <math.h> |
| 34 | |
| 35 | #include <libavutil/opt.h> |
| 36 | #include <libavcodec/avcodec.h> |
| 37 | #include <libavutil/channel_layout.h> |
| 38 | #include <libavutil/common.h> |
| 39 | #include <libavutil/imgutils.h> |
| 40 | #include <libavutil/mathematics.h> |
| 41 | #include <libavutil/samplefmt.h> |
| 42 | |
| 43 | #define INBUF_SIZE 4096 |
| 44 | #define AUDIO_INBUF_SIZE 20480 |
| 45 | #define AUDIO_REFILL_THRESH 4096 |
| 46 | |
| 47 | /* check that a given sample format is supported by the encoder */ |
| 48 | static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt) |
| 49 | { |
| 50 | const enum AVSampleFormat *p = codec->sample_fmts; |
| 51 | |
| 52 | while (*p != AV_SAMPLE_FMT_NONE) { |
| 53 | if (*p == sample_fmt) |
| 54 | return 1; |
| 55 | p++; |
| 56 | } |
| 57 | return 0; |
| 58 | } |
| 59 | |
| 60 | /* just pick the highest supported samplerate */ |
| 61 | static int select_sample_rate(AVCodec *codec) |
| 62 | { |
| 63 | const int *p; |
| 64 | int best_samplerate = 0; |
| 65 | |
| 66 | if (!codec->supported_samplerates) |
| 67 | return 44100; |
| 68 | |
| 69 | p = codec->supported_samplerates; |
| 70 | while (*p) { |
| 71 | best_samplerate = FFMAX(*p, best_samplerate); |
| 72 | p++; |
| 73 | } |
| 74 | return best_samplerate; |
| 75 | } |
| 76 | |
| 77 | /* select layout with the highest channel count */ |
| 78 | static int select_channel_layout(AVCodec *codec) |
| 79 | { |
| 80 | const uint64_t *p; |
| 81 | uint64_t best_ch_layout = 0; |
| 82 | int best_nb_channels = 0; |
| 83 | |
| 84 | if (!codec->channel_layouts) |
| 85 | return AV_CH_LAYOUT_STEREO; |
| 86 | |
| 87 | p = codec->channel_layouts; |
| 88 | while (*p) { |
| 89 | int nb_channels = av_get_channel_layout_nb_channels(*p); |
| 90 | |
| 91 | if (nb_channels > best_nb_channels) { |
| 92 | best_ch_layout = *p; |
| 93 | best_nb_channels = nb_channels; |
| 94 | } |
| 95 | p++; |
| 96 | } |
| 97 | return best_ch_layout; |
| 98 | } |
| 99 | |
| 100 | /* |
| 101 | * Audio encoding example |
| 102 | */ |
| 103 | static void audio_encode_example(const char *filename) |
| 104 | { |
| 105 | AVCodec *codec; |
| 106 | AVCodecContext *c= NULL; |
| 107 | AVFrame *frame; |
| 108 | AVPacket pkt; |
| 109 | int i, j, k, ret, got_output; |
| 110 | int buffer_size; |
| 111 | FILE *f; |
| 112 | uint16_t *samples; |
| 113 | float t, tincr; |
| 114 | |
| 115 | printf("Encode audio file %s\n", filename); |
| 116 | |
| 117 | /* find the MP2 encoder */ |
| 118 | codec = avcodec_find_encoder(AV_CODEC_ID_MP2); |
| 119 | if (!codec) { |
| 120 | fprintf(stderr, "Codec not found\n"); |
| 121 | exit(1); |
| 122 | } |
| 123 | |
| 124 | c = avcodec_alloc_context3(codec); |
| 125 | if (!c) { |
| 126 | fprintf(stderr, "Could not allocate audio codec context\n"); |
| 127 | exit(1); |
| 128 | } |
| 129 | |
| 130 | /* put sample parameters */ |
| 131 | c->bit_rate = 64000; |
| 132 | |
| 133 | /* check that the encoder supports s16 pcm input */ |
| 134 | c->sample_fmt = AV_SAMPLE_FMT_S16; |
| 135 | if (!check_sample_fmt(codec, c->sample_fmt)) { |
| 136 | fprintf(stderr, "Encoder does not support sample format %s", |
| 137 | av_get_sample_fmt_name(c->sample_fmt)); |
| 138 | exit(1); |
| 139 | } |
| 140 | |
| 141 | /* select other audio parameters supported by the encoder */ |
| 142 | c->sample_rate = select_sample_rate(codec); |
| 143 | c->channel_layout = select_channel_layout(codec); |
| 144 | c->channels = av_get_channel_layout_nb_channels(c->channel_layout); |
| 145 | |
| 146 | /* open it */ |
| 147 | if (avcodec_open2(c, codec, NULL) < 0) { |
| 148 | fprintf(stderr, "Could not open codec\n"); |
| 149 | exit(1); |
| 150 | } |
| 151 | |
| 152 | f = fopen(filename, "wb"); |
| 153 | if (!f) { |
| 154 | fprintf(stderr, "Could not open %s\n", filename); |
| 155 | exit(1); |
| 156 | } |
| 157 | |
| 158 | /* frame containing input raw audio */ |
| 159 | frame = av_frame_alloc(); |
| 160 | if (!frame) { |
| 161 | fprintf(stderr, "Could not allocate audio frame\n"); |
| 162 | exit(1); |
| 163 | } |
| 164 | |
| 165 | frame->nb_samples = c->frame_size; |
| 166 | frame->format = c->sample_fmt; |
| 167 | frame->channel_layout = c->channel_layout; |
| 168 | |
| 169 | /* the codec gives us the frame size, in samples, |
| 170 | * we calculate the size of the samples buffer in bytes */ |
| 171 | buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size, |
| 172 | c->sample_fmt, 0); |
| 173 | if (buffer_size < 0) { |
| 174 | fprintf(stderr, "Could not get sample buffer size\n"); |
| 175 | exit(1); |
| 176 | } |
| 177 | samples = av_malloc(buffer_size); |
| 178 | if (!samples) { |
| 179 | fprintf(stderr, "Could not allocate %d bytes for samples buffer\n", |
| 180 | buffer_size); |
| 181 | exit(1); |
| 182 | } |
| 183 | /* setup the data pointers in the AVFrame */ |
| 184 | ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt, |
| 185 | (const uint8_t*)samples, buffer_size, 0); |
| 186 | if (ret < 0) { |
| 187 | fprintf(stderr, "Could not setup audio frame\n"); |
| 188 | exit(1); |
| 189 | } |
| 190 | |
| 191 | /* encode a single tone sound */ |
| 192 | t = 0; |
| 193 | tincr = 2 * M_PI * 440.0 / c->sample_rate; |
| 194 | for (i = 0; i < 200; i++) { |
| 195 | av_init_packet(&pkt); |
| 196 | pkt.data = NULL; // packet data will be allocated by the encoder |
| 197 | pkt.size = 0; |
| 198 | |
| 199 | for (j = 0; j < c->frame_size; j++) { |
| 200 | samples[2*j] = (int)(sin(t) * 10000); |
| 201 | |
| 202 | for (k = 1; k < c->channels; k++) |
| 203 | samples[2*j + k] = samples[2*j]; |
| 204 | t += tincr; |
| 205 | } |
| 206 | /* encode the samples */ |
| 207 | ret = avcodec_encode_audio2(c, &pkt, frame, &got_output); |
| 208 | if (ret < 0) { |
| 209 | fprintf(stderr, "Error encoding audio frame\n"); |
| 210 | exit(1); |
| 211 | } |
| 212 | if (got_output) { |
| 213 | fwrite(pkt.data, 1, pkt.size, f); |
| 214 | av_free_packet(&pkt); |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | /* get the delayed frames */ |
| 219 | for (got_output = 1; got_output; i++) { |
| 220 | ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output); |
| 221 | if (ret < 0) { |
| 222 | fprintf(stderr, "Error encoding frame\n"); |
| 223 | exit(1); |
| 224 | } |
| 225 | |
| 226 | if (got_output) { |
| 227 | fwrite(pkt.data, 1, pkt.size, f); |
| 228 | av_free_packet(&pkt); |
| 229 | } |
| 230 | } |
| 231 | fclose(f); |
| 232 | |
| 233 | av_freep(&samples); |
| 234 | av_frame_free(&frame); |
| 235 | avcodec_close(c); |
| 236 | av_free(c); |
| 237 | } |
| 238 | |
| 239 | /* |
| 240 | * Audio decoding. |
| 241 | */ |
| 242 | static void audio_decode_example(const char *outfilename, const char *filename) |
| 243 | { |
| 244 | AVCodec *codec; |
| 245 | AVCodecContext *c= NULL; |
| 246 | int len; |
| 247 | FILE *f, *outfile; |
| 248 | uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; |
| 249 | AVPacket avpkt; |
| 250 | AVFrame *decoded_frame = NULL; |
| 251 | |
| 252 | av_init_packet(&avpkt); |
| 253 | |
| 254 | printf("Decode audio file %s to %s\n", filename, outfilename); |
| 255 | |
| 256 | /* find the mpeg audio decoder */ |
| 257 | codec = avcodec_find_decoder(AV_CODEC_ID_MP2); |
| 258 | if (!codec) { |
| 259 | fprintf(stderr, "Codec not found\n"); |
| 260 | exit(1); |
| 261 | } |
| 262 | |
| 263 | c = avcodec_alloc_context3(codec); |
| 264 | if (!c) { |
| 265 | fprintf(stderr, "Could not allocate audio codec context\n"); |
| 266 | exit(1); |
| 267 | } |
| 268 | |
| 269 | /* open it */ |
| 270 | if (avcodec_open2(c, codec, NULL) < 0) { |
| 271 | fprintf(stderr, "Could not open codec\n"); |
| 272 | exit(1); |
| 273 | } |
| 274 | |
| 275 | f = fopen(filename, "rb"); |
| 276 | if (!f) { |
| 277 | fprintf(stderr, "Could not open %s\n", filename); |
| 278 | exit(1); |
| 279 | } |
| 280 | outfile = fopen(outfilename, "wb"); |
| 281 | if (!outfile) { |
| 282 | av_free(c); |
| 283 | exit(1); |
| 284 | } |
| 285 | |
| 286 | /* decode until eof */ |
| 287 | avpkt.data = inbuf; |
| 288 | avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f); |
| 289 | |
| 290 | while (avpkt.size > 0) { |
| 291 | int i, ch; |
| 292 | int got_frame = 0; |
| 293 | |
| 294 | if (!decoded_frame) { |
| 295 | if (!(decoded_frame = av_frame_alloc())) { |
| 296 | fprintf(stderr, "Could not allocate audio frame\n"); |
| 297 | exit(1); |
| 298 | } |
| 299 | } |
| 300 | |
| 301 | len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt); |
| 302 | if (len < 0) { |
| 303 | fprintf(stderr, "Error while decoding\n"); |
| 304 | exit(1); |
| 305 | } |
| 306 | if (got_frame) { |
| 307 | /* if a frame has been decoded, output it */ |
| 308 | int data_size = av_get_bytes_per_sample(c->sample_fmt); |
| 309 | if (data_size < 0) { |
| 310 | /* This should not occur, checking just for paranoia */ |
| 311 | fprintf(stderr, "Failed to calculate data size\n"); |
| 312 | exit(1); |
| 313 | } |
| 314 | for (i=0; i<decoded_frame->nb_samples; i++) |
| 315 | for (ch=0; ch<c->channels; ch++) |
| 316 | fwrite(decoded_frame->data[ch] + data_size*i, 1, data_size, outfile); |
| 317 | } |
| 318 | avpkt.size -= len; |
| 319 | avpkt.data += len; |
| 320 | avpkt.dts = |
| 321 | avpkt.pts = AV_NOPTS_VALUE; |
| 322 | if (avpkt.size < AUDIO_REFILL_THRESH) { |
| 323 | /* Refill the input buffer, to avoid trying to decode |
| 324 | * incomplete frames. Instead of this, one could also use |
| 325 | * a parser, or use a proper container format through |
| 326 | * libavformat. */ |
| 327 | memmove(inbuf, avpkt.data, avpkt.size); |
| 328 | avpkt.data = inbuf; |
| 329 | len = fread(avpkt.data + avpkt.size, 1, |
| 330 | AUDIO_INBUF_SIZE - avpkt.size, f); |
| 331 | if (len > 0) |
| 332 | avpkt.size += len; |
| 333 | } |
| 334 | } |
| 335 | |
| 336 | fclose(outfile); |
| 337 | fclose(f); |
| 338 | |
| 339 | avcodec_close(c); |
| 340 | av_free(c); |
| 341 | av_frame_free(&decoded_frame); |
| 342 | } |
| 343 | |
| 344 | /* |
| 345 | * Video encoding example |
| 346 | */ |
| 347 | static void video_encode_example(const char *filename, int codec_id) |
| 348 | { |
| 349 | AVCodec *codec; |
| 350 | AVCodecContext *c= NULL; |
| 351 | int i, ret, x, y, got_output; |
| 352 | FILE *f; |
| 353 | AVFrame *frame; |
| 354 | AVPacket pkt; |
| 355 | uint8_t endcode[] = { 0, 0, 1, 0xb7 }; |
| 356 | |
| 357 | printf("Encode video file %s\n", filename); |
| 358 | |
| 359 | /* find the mpeg1 video encoder */ |
| 360 | codec = avcodec_find_encoder(codec_id); |
| 361 | if (!codec) { |
| 362 | fprintf(stderr, "Codec not found\n"); |
| 363 | exit(1); |
| 364 | } |
| 365 | |
| 366 | c = avcodec_alloc_context3(codec); |
| 367 | if (!c) { |
| 368 | fprintf(stderr, "Could not allocate video codec context\n"); |
| 369 | exit(1); |
| 370 | } |
| 371 | |
| 372 | /* put sample parameters */ |
| 373 | c->bit_rate = 400000; |
| 374 | /* resolution must be a multiple of two */ |
| 375 | c->width = 352; |
| 376 | c->height = 288; |
| 377 | /* frames per second */ |
| 378 | c->time_base = (AVRational){1,25}; |
| 379 | /* emit one intra frame every ten frames |
| 380 | * check frame pict_type before passing frame |
| 381 | * to encoder, if frame->pict_type is AV_PICTURE_TYPE_I |
| 382 | * then gop_size is ignored and the output of encoder |
| 383 | * will always be I frame irrespective to gop_size |
| 384 | */ |
| 385 | c->gop_size = 10; |
| 386 | c->max_b_frames = 1; |
| 387 | c->pix_fmt = AV_PIX_FMT_YUV420P; |
| 388 | |
| 389 | if (codec_id == AV_CODEC_ID_H264) |
| 390 | av_opt_set(c->priv_data, "preset", "slow", 0); |
| 391 | |
| 392 | /* open it */ |
| 393 | if (avcodec_open2(c, codec, NULL) < 0) { |
| 394 | fprintf(stderr, "Could not open codec\n"); |
| 395 | exit(1); |
| 396 | } |
| 397 | |
| 398 | f = fopen(filename, "wb"); |
| 399 | if (!f) { |
| 400 | fprintf(stderr, "Could not open %s\n", filename); |
| 401 | exit(1); |
| 402 | } |
| 403 | |
| 404 | frame = av_frame_alloc(); |
| 405 | if (!frame) { |
| 406 | fprintf(stderr, "Could not allocate video frame\n"); |
| 407 | exit(1); |
| 408 | } |
| 409 | frame->format = c->pix_fmt; |
| 410 | frame->width = c->width; |
| 411 | frame->height = c->height; |
| 412 | |
| 413 | /* the image can be allocated by any means and av_image_alloc() is |
| 414 | * just the most convenient way if av_malloc() is to be used */ |
| 415 | ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, |
| 416 | c->pix_fmt, 32); |
| 417 | if (ret < 0) { |
| 418 | fprintf(stderr, "Could not allocate raw picture buffer\n"); |
| 419 | exit(1); |
| 420 | } |
| 421 | |
| 422 | /* encode 1 second of video */ |
| 423 | for (i = 0; i < 25; i++) { |
| 424 | av_init_packet(&pkt); |
| 425 | pkt.data = NULL; // packet data will be allocated by the encoder |
| 426 | pkt.size = 0; |
| 427 | |
| 428 | fflush(stdout); |
| 429 | /* prepare a dummy image */ |
| 430 | /* Y */ |
| 431 | for (y = 0; y < c->height; y++) { |
| 432 | for (x = 0; x < c->width; x++) { |
| 433 | frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3; |
| 434 | } |
| 435 | } |
| 436 | |
| 437 | /* Cb and Cr */ |
| 438 | for (y = 0; y < c->height/2; y++) { |
| 439 | for (x = 0; x < c->width/2; x++) { |
| 440 | frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2; |
| 441 | frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5; |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | frame->pts = i; |
| 446 | |
| 447 | /* encode the image */ |
| 448 | ret = avcodec_encode_video2(c, &pkt, frame, &got_output); |
| 449 | if (ret < 0) { |
| 450 | fprintf(stderr, "Error encoding frame\n"); |
| 451 | exit(1); |
| 452 | } |
| 453 | |
| 454 | if (got_output) { |
| 455 | printf("Write frame %3d (size=%5d)\n", i, pkt.size); |
| 456 | fwrite(pkt.data, 1, pkt.size, f); |
| 457 | av_free_packet(&pkt); |
| 458 | } |
| 459 | } |
| 460 | |
| 461 | /* get the delayed frames */ |
| 462 | for (got_output = 1; got_output; i++) { |
| 463 | fflush(stdout); |
| 464 | |
| 465 | ret = avcodec_encode_video2(c, &pkt, NULL, &got_output); |
| 466 | if (ret < 0) { |
| 467 | fprintf(stderr, "Error encoding frame\n"); |
| 468 | exit(1); |
| 469 | } |
| 470 | |
| 471 | if (got_output) { |
| 472 | printf("Write frame %3d (size=%5d)\n", i, pkt.size); |
| 473 | fwrite(pkt.data, 1, pkt.size, f); |
| 474 | av_free_packet(&pkt); |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | /* add sequence end code to have a real mpeg file */ |
| 479 | fwrite(endcode, 1, sizeof(endcode), f); |
| 480 | fclose(f); |
| 481 | |
| 482 | avcodec_close(c); |
| 483 | av_free(c); |
| 484 | av_freep(&frame->data[0]); |
| 485 | av_frame_free(&frame); |
| 486 | printf("\n"); |
| 487 | } |
| 488 | |
| 489 | /* |
| 490 | * Video decoding example |
| 491 | */ |
| 492 | |
| 493 | static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, |
| 494 | char *filename) |
| 495 | { |
| 496 | FILE *f; |
| 497 | int i; |
| 498 | |
| 499 | f = fopen(filename,"w"); |
| 500 | fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255); |
| 501 | for (i = 0; i < ysize; i++) |
| 502 | fwrite(buf + i * wrap, 1, xsize, f); |
| 503 | fclose(f); |
| 504 | } |
| 505 | |
| 506 | static int decode_write_frame(const char *outfilename, AVCodecContext *avctx, |
| 507 | AVFrame *frame, int *frame_count, AVPacket *pkt, int last) |
| 508 | { |
| 509 | int len, got_frame; |
| 510 | char buf[1024]; |
| 511 | |
| 512 | len = avcodec_decode_video2(avctx, frame, &got_frame, pkt); |
| 513 | if (len < 0) { |
| 514 | fprintf(stderr, "Error while decoding frame %d\n", *frame_count); |
| 515 | return len; |
| 516 | } |
| 517 | if (got_frame) { |
| 518 | printf("Saving %sframe %3d\n", last ? "last " : "", *frame_count); |
| 519 | fflush(stdout); |
| 520 | |
| 521 | /* the picture is allocated by the decoder, no need to free it */ |
| 522 | snprintf(buf, sizeof(buf), outfilename, *frame_count); |
| 523 | pgm_save(frame->data[0], frame->linesize[0], |
| 524 | avctx->width, avctx->height, buf); |
| 525 | (*frame_count)++; |
| 526 | } |
| 527 | if (pkt->data) { |
| 528 | pkt->size -= len; |
| 529 | pkt->data += len; |
| 530 | } |
| 531 | return 0; |
| 532 | } |
| 533 | |
| 534 | static void video_decode_example(const char *outfilename, const char *filename) |
| 535 | { |
| 536 | AVCodec *codec; |
| 537 | AVCodecContext *c= NULL; |
| 538 | int frame_count; |
| 539 | FILE *f; |
| 540 | AVFrame *frame; |
| 541 | uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; |
| 542 | AVPacket avpkt; |
| 543 | |
| 544 | av_init_packet(&avpkt); |
| 545 | |
| 546 | /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ |
| 547 | memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); |
| 548 | |
| 549 | printf("Decode video file %s to %s\n", filename, outfilename); |
| 550 | |
| 551 | /* find the mpeg1 video decoder */ |
| 552 | codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO); |
| 553 | if (!codec) { |
| 554 | fprintf(stderr, "Codec not found\n"); |
| 555 | exit(1); |
| 556 | } |
| 557 | |
| 558 | c = avcodec_alloc_context3(codec); |
| 559 | if (!c) { |
| 560 | fprintf(stderr, "Could not allocate video codec context\n"); |
| 561 | exit(1); |
| 562 | } |
| 563 | |
| 564 | if(codec->capabilities&CODEC_CAP_TRUNCATED) |
| 565 | c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ |
| 566 | |
| 567 | /* For some codecs, such as msmpeg4 and mpeg4, width and height |
| 568 | MUST be initialized there because this information is not |
| 569 | available in the bitstream. */ |
| 570 | |
| 571 | /* open it */ |
| 572 | if (avcodec_open2(c, codec, NULL) < 0) { |
| 573 | fprintf(stderr, "Could not open codec\n"); |
| 574 | exit(1); |
| 575 | } |
| 576 | |
| 577 | f = fopen(filename, "rb"); |
| 578 | if (!f) { |
| 579 | fprintf(stderr, "Could not open %s\n", filename); |
| 580 | exit(1); |
| 581 | } |
| 582 | |
| 583 | frame = av_frame_alloc(); |
| 584 | if (!frame) { |
| 585 | fprintf(stderr, "Could not allocate video frame\n"); |
| 586 | exit(1); |
| 587 | } |
| 588 | |
| 589 | frame_count = 0; |
| 590 | for (;;) { |
| 591 | avpkt.size = fread(inbuf, 1, INBUF_SIZE, f); |
| 592 | if (avpkt.size == 0) |
| 593 | break; |
| 594 | |
| 595 | /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) |
| 596 | and this is the only method to use them because you cannot |
| 597 | know the compressed data size before analysing it. |
| 598 | |
| 599 | BUT some other codecs (msmpeg4, mpeg4) are inherently frame |
| 600 | based, so you must call them with all the data for one |
| 601 | frame exactly. You must also initialize 'width' and |
| 602 | 'height' before initializing them. */ |
| 603 | |
| 604 | /* NOTE2: some codecs allow the raw parameters (frame size, |
| 605 | sample rate) to be changed at any frame. We handle this, so |
| 606 | you should also take care of it */ |
| 607 | |
| 608 | /* here, we use a stream based decoder (mpeg1video), so we |
| 609 | feed decoder and see if it could decode a frame */ |
| 610 | avpkt.data = inbuf; |
| 611 | while (avpkt.size > 0) |
| 612 | if (decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 0) < 0) |
| 613 | exit(1); |
| 614 | } |
| 615 | |
| 616 | /* some codecs, such as MPEG, transmit the I and P frame with a |
| 617 | latency of one frame. You must do the following to have a |
| 618 | chance to get the last frame of the video */ |
| 619 | avpkt.data = NULL; |
| 620 | avpkt.size = 0; |
| 621 | decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 1); |
| 622 | |
| 623 | fclose(f); |
| 624 | |
| 625 | avcodec_close(c); |
| 626 | av_free(c); |
| 627 | av_frame_free(&frame); |
| 628 | printf("\n"); |
| 629 | } |
| 630 | |
| 631 | int main(int argc, char **argv) |
| 632 | { |
| 633 | const char *output_type; |
| 634 | |
| 635 | /* register all the codecs */ |
| 636 | avcodec_register_all(); |
| 637 | |
| 638 | if (argc < 2) { |
| 639 | printf("usage: %s output_type\n" |
| 640 | "API example program to decode/encode a media stream with libavcodec.\n" |
| 641 | "This program generates a synthetic stream and encodes it to a file\n" |
| 642 | "named test.h264, test.mp2 or test.mpg depending on output_type.\n" |
| 643 | "The encoded stream is then decoded and written to a raw data output.\n" |
| 644 | "output_type must be chosen between 'h264', 'mp2', 'mpg'.\n", |
| 645 | argv[0]); |
| 646 | return 1; |
| 647 | } |
| 648 | output_type = argv[1]; |
| 649 | |
| 650 | if (!strcmp(output_type, "h264")) { |
| 651 | video_encode_example("test.h264", AV_CODEC_ID_H264); |
| 652 | } else if (!strcmp(output_type, "mp2")) { |
| 653 | audio_encode_example("test.mp2"); |
| 654 | audio_decode_example("test.pcm", "test.mp2"); |
| 655 | } else if (!strcmp(output_type, "mpg")) { |
| 656 | video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO); |
| 657 | video_decode_example("test%02d.pgm", "test.mpg"); |
| 658 | } else { |
| 659 | fprintf(stderr, "Invalid output type '%s', choose between 'h264', 'mp2', or 'mpg'\n", |
| 660 | output_type); |
| 661 | return 1; |
| 662 | } |
| 663 | |
| 664 | return 0; |
| 665 | } |