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| 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 got_frame = 0; | ||
| 292 | |||
| 293 | if (!decoded_frame) { | ||
| 294 | if (!(decoded_frame = av_frame_alloc())) { | ||
| 295 | fprintf(stderr, "Could not allocate audio frame\n"); | ||
| 296 | exit(1); | ||
| 297 | } | ||
| 298 | } | ||
| 299 | |||
| 300 | len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt); | ||
| 301 | if (len < 0) { | ||
| 302 | fprintf(stderr, "Error while decoding\n"); | ||
| 303 | exit(1); | ||
| 304 | } | ||
| 305 | if (got_frame) { | ||
| 306 | /* if a frame has been decoded, output it */ | ||
| 307 | int data_size = av_samples_get_buffer_size(NULL, c->channels, | ||
| 308 | decoded_frame->nb_samples, | ||
| 309 | c->sample_fmt, 1); | ||
| 310 | if (data_size < 0) { | ||
| 311 | /* This should not occur, checking just for paranoia */ | ||
| 312 | fprintf(stderr, "Failed to calculate data size\n"); | ||
| 313 | exit(1); | ||
| 314 | } | ||
| 315 | fwrite(decoded_frame->data[0], 1, data_size, outfile); | ||
| 316 | } | ||
| 317 | avpkt.size -= len; | ||
| 318 | avpkt.data += len; | ||
| 319 | avpkt.dts = | ||
| 320 | avpkt.pts = AV_NOPTS_VALUE; | ||
| 321 | if (avpkt.size < AUDIO_REFILL_THRESH) { | ||
| 322 | /* Refill the input buffer, to avoid trying to decode | ||
| 323 | * incomplete frames. Instead of this, one could also use | ||
| 324 | * a parser, or use a proper container format through | ||
| 325 | * libavformat. */ | ||
| 326 | memmove(inbuf, avpkt.data, avpkt.size); | ||
| 327 | avpkt.data = inbuf; | ||
| 328 | len = fread(avpkt.data + avpkt.size, 1, | ||
| 329 | AUDIO_INBUF_SIZE - avpkt.size, f); | ||
| 330 | if (len > 0) | ||
| 331 | avpkt.size += len; | ||
| 332 | } | ||
| 333 | } | ||
| 334 | |||
| 335 | fclose(outfile); | ||
| 336 | fclose(f); | ||
| 337 | |||
| 338 | avcodec_close(c); | ||
| 339 | av_free(c); | ||
| 340 | av_frame_free(&decoded_frame); | ||
| 341 | } | ||
| 342 | |||
| 343 | /* | ||
| 344 | * Video encoding example | ||
| 345 | */ | ||
| 346 | static void video_encode_example(const char *filename, int codec_id) | ||
| 347 | { | ||
| 348 | AVCodec *codec; | ||
| 349 | AVCodecContext *c= NULL; | ||
| 350 | int i, ret, x, y, got_output; | ||
| 351 | FILE *f; | ||
| 352 | AVFrame *frame; | ||
| 353 | AVPacket pkt; | ||
| 354 | uint8_t endcode[] = { 0, 0, 1, 0xb7 }; | ||
| 355 | |||
| 356 | printf("Encode video file %s\n", filename); | ||
| 357 | |||
| 358 | /* find the mpeg1 video encoder */ | ||
| 359 | codec = avcodec_find_encoder(codec_id); | ||
| 360 | if (!codec) { | ||
| 361 | fprintf(stderr, "Codec not found\n"); | ||
| 362 | exit(1); | ||
| 363 | } | ||
| 364 | |||
| 365 | c = avcodec_alloc_context3(codec); | ||
| 366 | if (!c) { | ||
| 367 | fprintf(stderr, "Could not allocate video codec context\n"); | ||
| 368 | exit(1); | ||
| 369 | } | ||
| 370 | |||
| 371 | /* put sample parameters */ | ||
| 372 | c->bit_rate = 400000; | ||
| 373 | /* resolution must be a multiple of two */ | ||
| 374 | c->width = 352; | ||
| 375 | c->height = 288; | ||
| 376 | /* frames per second */ | ||
| 377 | c->time_base = (AVRational){1,25}; | ||
| 378 | /* emit one intra frame every ten frames | ||
| 379 | * check frame pict_type before passing frame | ||
| 380 | * to encoder, if frame->pict_type is AV_PICTURE_TYPE_I | ||
| 381 | * then gop_size is ignored and the output of encoder | ||
| 382 | * will always be I frame irrespective to gop_size | ||
| 383 | */ | ||
| 384 | c->gop_size = 10; | ||
| 385 | c->max_b_frames = 1; | ||
| 386 | c->pix_fmt = AV_PIX_FMT_YUV420P; | ||
| 387 | |||
| 388 | if (codec_id == AV_CODEC_ID_H264) | ||
| 389 | av_opt_set(c->priv_data, "preset", "slow", 0); | ||
| 390 | |||
| 391 | /* open it */ | ||
| 392 | if (avcodec_open2(c, codec, NULL) < 0) { | ||
| 393 | fprintf(stderr, "Could not open codec\n"); | ||
| 394 | exit(1); | ||
| 395 | } | ||
| 396 | |||
| 397 | f = fopen(filename, "wb"); | ||
| 398 | if (!f) { | ||
| 399 | fprintf(stderr, "Could not open %s\n", filename); | ||
| 400 | exit(1); | ||
| 401 | } | ||
| 402 | |||
| 403 | frame = av_frame_alloc(); | ||
| 404 | if (!frame) { | ||
| 405 | fprintf(stderr, "Could not allocate video frame\n"); | ||
| 406 | exit(1); | ||
| 407 | } | ||
| 408 | frame->format = c->pix_fmt; | ||
| 409 | frame->width = c->width; | ||
| 410 | frame->height = c->height; | ||
| 411 | |||
| 412 | /* the image can be allocated by any means and av_image_alloc() is | ||
| 413 | * just the most convenient way if av_malloc() is to be used */ | ||
| 414 | ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, | ||
| 415 | c->pix_fmt, 32); | ||
| 416 | if (ret < 0) { | ||
| 417 | fprintf(stderr, "Could not allocate raw picture buffer\n"); | ||
| 418 | exit(1); | ||
| 419 | } | ||
| 420 | |||
| 421 | /* encode 1 second of video */ | ||
| 422 | for (i = 0; i < 25; i++) { | ||
| 423 | av_init_packet(&pkt); | ||
| 424 | pkt.data = NULL; // packet data will be allocated by the encoder | ||
| 425 | pkt.size = 0; | ||
| 426 | |||
| 427 | fflush(stdout); | ||
| 428 | /* prepare a dummy image */ | ||
| 429 | /* Y */ | ||
| 430 | for (y = 0; y < c->height; y++) { | ||
| 431 | for (x = 0; x < c->width; x++) { | ||
| 432 | frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3; | ||
| 433 | } | ||
| 434 | } | ||
| 435 | |||
| 436 | /* Cb and Cr */ | ||
| 437 | for (y = 0; y < c->height/2; y++) { | ||
| 438 | for (x = 0; x < c->width/2; x++) { | ||
| 439 | frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2; | ||
| 440 | frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5; | ||
| 441 | } | ||
| 442 | } | ||
| 443 | |||
| 444 | frame->pts = i; | ||
| 445 | |||
| 446 | /* encode the image */ | ||
| 447 | ret = avcodec_encode_video2(c, &pkt, frame, &got_output); | ||
| 448 | if (ret < 0) { | ||
| 449 | fprintf(stderr, "Error encoding frame\n"); | ||
| 450 | exit(1); | ||
| 451 | } | ||
| 452 | |||
| 453 | if (got_output) { | ||
| 454 | printf("Write frame %3d (size=%5d)\n", i, pkt.size); | ||
| 455 | fwrite(pkt.data, 1, pkt.size, f); | ||
| 456 | av_free_packet(&pkt); | ||
| 457 | } | ||
| 458 | } | ||
| 459 | |||
| 460 | /* get the delayed frames */ | ||
| 461 | for (got_output = 1; got_output; i++) { | ||
| 462 | fflush(stdout); | ||
| 463 | |||
| 464 | ret = avcodec_encode_video2(c, &pkt, NULL, &got_output); | ||
| 465 | if (ret < 0) { | ||
| 466 | fprintf(stderr, "Error encoding frame\n"); | ||
| 467 | exit(1); | ||
| 468 | } | ||
| 469 | |||
| 470 | if (got_output) { | ||
| 471 | printf("Write frame %3d (size=%5d)\n", i, pkt.size); | ||
| 472 | fwrite(pkt.data, 1, pkt.size, f); | ||
| 473 | av_free_packet(&pkt); | ||
| 474 | } | ||
| 475 | } | ||
| 476 | |||
| 477 | /* add sequence end code to have a real mpeg file */ | ||
| 478 | fwrite(endcode, 1, sizeof(endcode), f); | ||
| 479 | fclose(f); | ||
| 480 | |||
| 481 | avcodec_close(c); | ||
| 482 | av_free(c); | ||
| 483 | av_freep(&frame->data[0]); | ||
| 484 | av_frame_free(&frame); | ||
| 485 | printf("\n"); | ||
| 486 | } | ||
| 487 | |||
| 488 | /* | ||
| 489 | * Video decoding example | ||
| 490 | */ | ||
| 491 | |||
| 492 | static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, | ||
| 493 | char *filename) | ||
| 494 | { | ||
| 495 | FILE *f; | ||
| 496 | int i; | ||
| 497 | |||
| 498 | f = fopen(filename,"w"); | ||
| 499 | fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255); | ||
| 500 | for (i = 0; i < ysize; i++) | ||
| 501 | fwrite(buf + i * wrap, 1, xsize, f); | ||
| 502 | fclose(f); | ||
| 503 | } | ||
| 504 | |||
| 505 | static int decode_write_frame(const char *outfilename, AVCodecContext *avctx, | ||
| 506 | AVFrame *frame, int *frame_count, AVPacket *pkt, int last) | ||
| 507 | { | ||
| 508 | int len, got_frame; | ||
| 509 | char buf[1024]; | ||
| 510 | |||
| 511 | len = avcodec_decode_video2(avctx, frame, &got_frame, pkt); | ||
| 512 | if (len < 0) { | ||
| 513 | fprintf(stderr, "Error while decoding frame %d\n", *frame_count); | ||
| 514 | return len; | ||
| 515 | } | ||
| 516 | if (got_frame) { | ||
| 517 | printf("Saving %sframe %3d\n", last ? "last " : "", *frame_count); | ||
| 518 | fflush(stdout); | ||
| 519 | |||
| 520 | /* the picture is allocated by the decoder, no need to free it */ | ||
| 521 | snprintf(buf, sizeof(buf), outfilename, *frame_count); | ||
| 522 | pgm_save(frame->data[0], frame->linesize[0], | ||
| 523 | avctx->width, avctx->height, buf); | ||
| 524 | (*frame_count)++; | ||
| 525 | } | ||
| 526 | if (pkt->data) { | ||
| 527 | pkt->size -= len; | ||
| 528 | pkt->data += len; | ||
| 529 | } | ||
| 530 | return 0; | ||
| 531 | } | ||
| 532 | |||
| 533 | static void video_decode_example(const char *outfilename, const char *filename) | ||
| 534 | { | ||
| 535 | AVCodec *codec; | ||
| 536 | AVCodecContext *c= NULL; | ||
| 537 | int frame_count; | ||
| 538 | FILE *f; | ||
| 539 | AVFrame *frame; | ||
| 540 | uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; | ||
| 541 | AVPacket avpkt; | ||
| 542 | |||
| 543 | av_init_packet(&avpkt); | ||
| 544 | |||
| 545 | /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ | ||
| 546 | memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); | ||
| 547 | |||
| 548 | printf("Decode video file %s to %s\n", filename, outfilename); | ||
| 549 | |||
| 550 | /* find the mpeg1 video decoder */ | ||
| 551 | codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO); | ||
| 552 | if (!codec) { | ||
| 553 | fprintf(stderr, "Codec not found\n"); | ||
| 554 | exit(1); | ||
| 555 | } | ||
| 556 | |||
| 557 | c = avcodec_alloc_context3(codec); | ||
| 558 | if (!c) { | ||
| 559 | fprintf(stderr, "Could not allocate video codec context\n"); | ||
| 560 | exit(1); | ||
| 561 | } | ||
| 562 | |||
| 563 | if(codec->capabilities&CODEC_CAP_TRUNCATED) | ||
| 564 | c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ | ||
| 565 | |||
| 566 | /* For some codecs, such as msmpeg4 and mpeg4, width and height | ||
| 567 | MUST be initialized there because this information is not | ||
| 568 | available in the bitstream. */ | ||
| 569 | |||
| 570 | /* open it */ | ||
| 571 | if (avcodec_open2(c, codec, NULL) < 0) { | ||
| 572 | fprintf(stderr, "Could not open codec\n"); | ||
| 573 | exit(1); | ||
| 574 | } | ||
| 575 | |||
| 576 | f = fopen(filename, "rb"); | ||
| 577 | if (!f) { | ||
| 578 | fprintf(stderr, "Could not open %s\n", filename); | ||
| 579 | exit(1); | ||
| 580 | } | ||
| 581 | |||
| 582 | frame = av_frame_alloc(); | ||
| 583 | if (!frame) { | ||
| 584 | fprintf(stderr, "Could not allocate video frame\n"); | ||
| 585 | exit(1); | ||
| 586 | } | ||
| 587 | |||
| 588 | frame_count = 0; | ||
| 589 | for (;;) { | ||
| 590 | avpkt.size = fread(inbuf, 1, INBUF_SIZE, f); | ||
| 591 | if (avpkt.size == 0) | ||
| 592 | break; | ||
| 593 | |||
| 594 | /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) | ||
| 595 | and this is the only method to use them because you cannot | ||
| 596 | know the compressed data size before analysing it. | ||
| 597 | |||
| 598 | BUT some other codecs (msmpeg4, mpeg4) are inherently frame | ||
| 599 | based, so you must call them with all the data for one | ||
| 600 | frame exactly. You must also initialize 'width' and | ||
| 601 | 'height' before initializing them. */ | ||
| 602 | |||
| 603 | /* NOTE2: some codecs allow the raw parameters (frame size, | ||
| 604 | sample rate) to be changed at any frame. We handle this, so | ||
| 605 | you should also take care of it */ | ||
| 606 | |||
| 607 | /* here, we use a stream based decoder (mpeg1video), so we | ||
| 608 | feed decoder and see if it could decode a frame */ | ||
| 609 | avpkt.data = inbuf; | ||
| 610 | while (avpkt.size > 0) | ||
| 611 | if (decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 0) < 0) | ||
| 612 | exit(1); | ||
| 613 | } | ||
| 614 | |||
| 615 | /* some codecs, such as MPEG, transmit the I and P frame with a | ||
| 616 | latency of one frame. You must do the following to have a | ||
| 617 | chance to get the last frame of the video */ | ||
| 618 | avpkt.data = NULL; | ||
| 619 | avpkt.size = 0; | ||
| 620 | decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 1); | ||
| 621 | |||
| 622 | fclose(f); | ||
| 623 | |||
| 624 | avcodec_close(c); | ||
| 625 | av_free(c); | ||
| 626 | av_frame_free(&frame); | ||
| 627 | printf("\n"); | ||
| 628 | } | ||
| 629 | |||
| 630 | int main(int argc, char **argv) | ||
| 631 | { | ||
| 632 | const char *output_type; | ||
| 633 | |||
| 634 | /* register all the codecs */ | ||
| 635 | avcodec_register_all(); | ||
| 636 | |||
| 637 | if (argc < 2) { | ||
| 638 | printf("usage: %s output_type\n" | ||
| 639 | "API example program to decode/encode a media stream with libavcodec.\n" | ||
| 640 | "This program generates a synthetic stream and encodes it to a file\n" | ||
| 641 | "named test.h264, test.mp2 or test.mpg depending on output_type.\n" | ||
| 642 | "The encoded stream is then decoded and written to a raw data output.\n" | ||
| 643 | "output_type must be choosen between 'h264', 'mp2', 'mpg'.\n", | ||
| 644 | argv[0]); | ||
| 645 | return 1; | ||
| 646 | } | ||
| 647 | output_type = argv[1]; | ||
| 648 | |||
| 649 | if (!strcmp(output_type, "h264")) { | ||
| 650 | video_encode_example("test.h264", AV_CODEC_ID_H264); | ||
| 651 | } else if (!strcmp(output_type, "mp2")) { | ||
| 652 | audio_encode_example("test.mp2"); | ||
| 653 | audio_decode_example("test.sw", "test.mp2"); | ||
| 654 | } else if (!strcmp(output_type, "mpg")) { | ||
| 655 | video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO); | ||
| 656 | video_decode_example("test%02d.pgm", "test.mpg"); | ||
| 657 | } else { | ||
| 658 | fprintf(stderr, "Invalid output type '%s', choose between 'h264', 'mp2', or 'mpg'\n", | ||
| 659 | output_type); | ||
| 660 | return 1; | ||
| 661 | } | ||
| 662 | |||
| 663 | return 0; | ||
| 664 | } | ||