yading@10: /* yading@10: * Copyright (c) 2001 Fabrice Bellard yading@10: * yading@10: * Permission is hereby granted, free of charge, to any person obtaining a copy yading@10: * of this software and associated documentation files (the "Software"), to deal yading@10: * in the Software without restriction, including without limitation the rights yading@10: * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell yading@10: * copies of the Software, and to permit persons to whom the Software is yading@10: * furnished to do so, subject to the following conditions: yading@10: * yading@10: * The above copyright notice and this permission notice shall be included in yading@10: * all copies or substantial portions of the Software. yading@10: * yading@10: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR yading@10: * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, yading@10: * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL yading@10: * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER yading@10: * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, yading@10: * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN yading@10: * THE SOFTWARE. yading@10: */ yading@10: yading@10: /** yading@10: * @file yading@10: * libavcodec API use example. yading@10: * yading@10: * Note that libavcodec only handles codecs (mpeg, mpeg4, etc...), yading@10: * not file formats (avi, vob, mp4, mov, mkv, mxf, flv, mpegts, mpegps, etc...). See library 'libavformat' for the yading@10: * format handling yading@10: * @example doc/examples/decoding_encoding.c yading@10: */ yading@10: yading@10: #include yading@10: yading@10: #include yading@10: #include yading@10: #include yading@10: #include yading@10: #include yading@10: #include yading@10: #include yading@10: yading@10: #define INBUF_SIZE 4096 yading@10: #define AUDIO_INBUF_SIZE 20480 yading@10: #define AUDIO_REFILL_THRESH 4096 yading@10: yading@10: /* check that a given sample format is supported by the encoder */ yading@10: static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt) yading@10: { yading@10: const enum AVSampleFormat *p = codec->sample_fmts; yading@10: yading@10: while (*p != AV_SAMPLE_FMT_NONE) { yading@10: if (*p == sample_fmt) yading@10: return 1; yading@10: p++; yading@10: } yading@10: return 0; yading@10: } yading@10: yading@10: /* just pick the highest supported samplerate */ yading@10: static int select_sample_rate(AVCodec *codec) yading@10: { yading@10: const int *p; yading@10: int best_samplerate = 0; yading@10: yading@10: if (!codec->supported_samplerates) yading@10: return 44100; yading@10: yading@10: p = codec->supported_samplerates; yading@10: while (*p) { yading@10: best_samplerate = FFMAX(*p, best_samplerate); yading@10: p++; yading@10: } yading@10: return best_samplerate; yading@10: } yading@10: yading@10: /* select layout with the highest channel count */ yading@10: static int select_channel_layout(AVCodec *codec) yading@10: { yading@10: const uint64_t *p; yading@10: uint64_t best_ch_layout = 0; yading@10: int best_nb_channels = 0; yading@10: yading@10: if (!codec->channel_layouts) yading@10: return AV_CH_LAYOUT_STEREO; yading@10: yading@10: p = codec->channel_layouts; yading@10: while (*p) { yading@10: int nb_channels = av_get_channel_layout_nb_channels(*p); yading@10: yading@10: if (nb_channels > best_nb_channels) { yading@10: best_ch_layout = *p; yading@10: best_nb_channels = nb_channels; yading@10: } yading@10: p++; yading@10: } yading@10: return best_ch_layout; yading@10: } yading@10: yading@10: /* yading@10: * Audio encoding example yading@10: */ yading@10: static void audio_encode_example(const char *filename) yading@10: { yading@10: AVCodec *codec; yading@10: AVCodecContext *c= NULL; yading@10: AVFrame *frame; yading@10: AVPacket pkt; yading@10: int i, j, k, ret, got_output; yading@10: int buffer_size; yading@10: FILE *f; yading@10: uint16_t *samples; yading@10: float t, tincr; yading@10: yading@10: printf("Encode audio file %s\n", filename); yading@10: yading@10: /* find the MP2 encoder */ yading@10: codec = avcodec_find_encoder(AV_CODEC_ID_MP2); yading@10: if (!codec) { yading@10: fprintf(stderr, "Codec not found\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: c = avcodec_alloc_context3(codec); yading@10: if (!c) { yading@10: fprintf(stderr, "Could not allocate audio codec context\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: /* put sample parameters */ yading@10: c->bit_rate = 64000; yading@10: yading@10: /* check that the encoder supports s16 pcm input */ yading@10: c->sample_fmt = AV_SAMPLE_FMT_S16; yading@10: if (!check_sample_fmt(codec, c->sample_fmt)) { yading@10: fprintf(stderr, "Encoder does not support sample format %s", yading@10: av_get_sample_fmt_name(c->sample_fmt)); yading@10: exit(1); yading@10: } yading@10: yading@10: /* select other audio parameters supported by the encoder */ yading@10: c->sample_rate = select_sample_rate(codec); yading@10: c->channel_layout = select_channel_layout(codec); yading@10: c->channels = av_get_channel_layout_nb_channels(c->channel_layout); yading@10: yading@10: /* open it */ yading@10: if (avcodec_open2(c, codec, NULL) < 0) { yading@10: fprintf(stderr, "Could not open codec\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: f = fopen(filename, "wb"); yading@10: if (!f) { yading@10: fprintf(stderr, "Could not open %s\n", filename); yading@10: exit(1); yading@10: } yading@10: yading@10: /* frame containing input raw audio */ yading@10: frame = avcodec_alloc_frame(); yading@10: if (!frame) { yading@10: fprintf(stderr, "Could not allocate audio frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: frame->nb_samples = c->frame_size; yading@10: frame->format = c->sample_fmt; yading@10: frame->channel_layout = c->channel_layout; yading@10: yading@10: /* the codec gives us the frame size, in samples, yading@10: * we calculate the size of the samples buffer in bytes */ yading@10: buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size, yading@10: c->sample_fmt, 0); yading@10: samples = av_malloc(buffer_size); yading@10: if (!samples) { yading@10: fprintf(stderr, "Could not allocate %d bytes for samples buffer\n", yading@10: buffer_size); yading@10: exit(1); yading@10: } yading@10: /* setup the data pointers in the AVFrame */ yading@10: ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt, yading@10: (const uint8_t*)samples, buffer_size, 0); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Could not setup audio frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: /* encode a single tone sound */ yading@10: t = 0; yading@10: tincr = 2 * M_PI * 440.0 / c->sample_rate; yading@10: for(i=0;i<200;i++) { yading@10: av_init_packet(&pkt); yading@10: pkt.data = NULL; // packet data will be allocated by the encoder yading@10: pkt.size = 0; yading@10: yading@10: for (j = 0; j < c->frame_size; j++) { yading@10: samples[2*j] = (int)(sin(t) * 10000); yading@10: yading@10: for (k = 1; k < c->channels; k++) yading@10: samples[2*j + k] = samples[2*j]; yading@10: t += tincr; yading@10: } yading@10: /* encode the samples */ yading@10: ret = avcodec_encode_audio2(c, &pkt, frame, &got_output); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Error encoding audio frame\n"); yading@10: exit(1); yading@10: } yading@10: if (got_output) { yading@10: fwrite(pkt.data, 1, pkt.size, f); yading@10: av_free_packet(&pkt); yading@10: } yading@10: } yading@10: yading@10: /* get the delayed frames */ yading@10: for (got_output = 1; got_output; i++) { yading@10: ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Error encoding frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: if (got_output) { yading@10: fwrite(pkt.data, 1, pkt.size, f); yading@10: av_free_packet(&pkt); yading@10: } yading@10: } yading@10: fclose(f); yading@10: yading@10: av_freep(&samples); yading@10: avcodec_free_frame(&frame); yading@10: avcodec_close(c); yading@10: av_free(c); yading@10: } yading@10: yading@10: /* yading@10: * Audio decoding. yading@10: */ yading@10: static void audio_decode_example(const char *outfilename, const char *filename) yading@10: { yading@10: AVCodec *codec; yading@10: AVCodecContext *c= NULL; yading@10: int len; yading@10: FILE *f, *outfile; yading@10: uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; yading@10: AVPacket avpkt; yading@10: AVFrame *decoded_frame = NULL; yading@10: yading@10: av_init_packet(&avpkt); yading@10: yading@10: printf("Decode audio file %s to %s\n", filename, outfilename); yading@10: yading@10: /* find the mpeg audio decoder */ yading@10: codec = avcodec_find_decoder(AV_CODEC_ID_MP2); yading@10: if (!codec) { yading@10: fprintf(stderr, "Codec not found\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: c = avcodec_alloc_context3(codec); yading@10: if (!c) { yading@10: fprintf(stderr, "Could not allocate audio codec context\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: /* open it */ yading@10: if (avcodec_open2(c, codec, NULL) < 0) { yading@10: fprintf(stderr, "Could not open codec\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: f = fopen(filename, "rb"); yading@10: if (!f) { yading@10: fprintf(stderr, "Could not open %s\n", filename); yading@10: exit(1); yading@10: } yading@10: outfile = fopen(outfilename, "wb"); yading@10: if (!outfile) { yading@10: av_free(c); yading@10: exit(1); yading@10: } yading@10: yading@10: /* decode until eof */ yading@10: avpkt.data = inbuf; yading@10: avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f); yading@10: yading@10: while (avpkt.size > 0) { yading@10: int got_frame = 0; yading@10: yading@10: if (!decoded_frame) { yading@10: if (!(decoded_frame = avcodec_alloc_frame())) { yading@10: fprintf(stderr, "Could not allocate audio frame\n"); yading@10: exit(1); yading@10: } yading@10: } else yading@10: avcodec_get_frame_defaults(decoded_frame); yading@10: yading@10: len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt); yading@10: if (len < 0) { yading@10: fprintf(stderr, "Error while decoding\n"); yading@10: exit(1); yading@10: } yading@10: if (got_frame) { yading@10: /* if a frame has been decoded, output it */ yading@10: int data_size = av_samples_get_buffer_size(NULL, c->channels, yading@10: decoded_frame->nb_samples, yading@10: c->sample_fmt, 1); yading@10: fwrite(decoded_frame->data[0], 1, data_size, outfile); yading@10: } yading@10: avpkt.size -= len; yading@10: avpkt.data += len; yading@10: avpkt.dts = yading@10: avpkt.pts = AV_NOPTS_VALUE; yading@10: if (avpkt.size < AUDIO_REFILL_THRESH) { yading@10: /* Refill the input buffer, to avoid trying to decode yading@10: * incomplete frames. Instead of this, one could also use yading@10: * a parser, or use a proper container format through yading@10: * libavformat. */ yading@10: memmove(inbuf, avpkt.data, avpkt.size); yading@10: avpkt.data = inbuf; yading@10: len = fread(avpkt.data + avpkt.size, 1, yading@10: AUDIO_INBUF_SIZE - avpkt.size, f); yading@10: if (len > 0) yading@10: avpkt.size += len; yading@10: } yading@10: } yading@10: yading@10: fclose(outfile); yading@10: fclose(f); yading@10: yading@10: avcodec_close(c); yading@10: av_free(c); yading@10: avcodec_free_frame(&decoded_frame); yading@10: } yading@10: yading@10: /* yading@10: * Video encoding example yading@10: */ yading@10: static void video_encode_example(const char *filename, int codec_id) yading@10: { yading@10: AVCodec *codec; yading@10: AVCodecContext *c= NULL; yading@10: int i, ret, x, y, got_output; yading@10: FILE *f; yading@10: AVFrame *frame; yading@10: AVPacket pkt; yading@10: uint8_t endcode[] = { 0, 0, 1, 0xb7 }; yading@10: yading@10: printf("Encode video file %s\n", filename); yading@10: yading@10: /* find the mpeg1 video encoder */ yading@10: codec = avcodec_find_encoder(codec_id); yading@10: if (!codec) { yading@10: fprintf(stderr, "Codec not found\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: c = avcodec_alloc_context3(codec); yading@10: if (!c) { yading@10: fprintf(stderr, "Could not allocate video codec context\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: /* put sample parameters */ yading@10: c->bit_rate = 400000; yading@10: /* resolution must be a multiple of two */ yading@10: c->width = 352; yading@10: c->height = 288; yading@10: /* frames per second */ yading@10: c->time_base= (AVRational){1,25}; yading@10: c->gop_size = 10; /* emit one intra frame every ten frames */ yading@10: c->max_b_frames=1; yading@10: c->pix_fmt = AV_PIX_FMT_YUV420P; yading@10: yading@10: if(codec_id == AV_CODEC_ID_H264) yading@10: av_opt_set(c->priv_data, "preset", "slow", 0); yading@10: yading@10: /* open it */ yading@10: if (avcodec_open2(c, codec, NULL) < 0) { yading@10: fprintf(stderr, "Could not open codec\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: f = fopen(filename, "wb"); yading@10: if (!f) { yading@10: fprintf(stderr, "Could not open %s\n", filename); yading@10: exit(1); yading@10: } yading@10: yading@10: frame = avcodec_alloc_frame(); yading@10: if (!frame) { yading@10: fprintf(stderr, "Could not allocate video frame\n"); yading@10: exit(1); yading@10: } yading@10: frame->format = c->pix_fmt; yading@10: frame->width = c->width; yading@10: frame->height = c->height; yading@10: yading@10: /* the image can be allocated by any means and av_image_alloc() is yading@10: * just the most convenient way if av_malloc() is to be used */ yading@10: ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, yading@10: c->pix_fmt, 32); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Could not allocate raw picture buffer\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: /* encode 1 second of video */ yading@10: for(i=0;i<25;i++) { yading@10: av_init_packet(&pkt); yading@10: pkt.data = NULL; // packet data will be allocated by the encoder yading@10: pkt.size = 0; yading@10: yading@10: fflush(stdout); yading@10: /* prepare a dummy image */ yading@10: /* Y */ yading@10: for(y=0;yheight;y++) { yading@10: for(x=0;xwidth;x++) { yading@10: frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3; yading@10: } yading@10: } yading@10: yading@10: /* Cb and Cr */ yading@10: for(y=0;yheight/2;y++) { yading@10: for(x=0;xwidth/2;x++) { yading@10: frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2; yading@10: frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5; yading@10: } yading@10: } yading@10: yading@10: frame->pts = i; yading@10: yading@10: /* encode the image */ yading@10: ret = avcodec_encode_video2(c, &pkt, frame, &got_output); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Error encoding frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: if (got_output) { yading@10: printf("Write frame %3d (size=%5d)\n", i, pkt.size); yading@10: fwrite(pkt.data, 1, pkt.size, f); yading@10: av_free_packet(&pkt); yading@10: } yading@10: } yading@10: yading@10: /* get the delayed frames */ yading@10: for (got_output = 1; got_output; i++) { yading@10: fflush(stdout); yading@10: yading@10: ret = avcodec_encode_video2(c, &pkt, NULL, &got_output); yading@10: if (ret < 0) { yading@10: fprintf(stderr, "Error encoding frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: if (got_output) { yading@10: printf("Write frame %3d (size=%5d)\n", i, pkt.size); yading@10: fwrite(pkt.data, 1, pkt.size, f); yading@10: av_free_packet(&pkt); yading@10: } yading@10: } yading@10: yading@10: /* add sequence end code to have a real mpeg file */ yading@10: fwrite(endcode, 1, sizeof(endcode), f); yading@10: fclose(f); yading@10: yading@10: avcodec_close(c); yading@10: av_free(c); yading@10: av_freep(&frame->data[0]); yading@10: avcodec_free_frame(&frame); yading@10: printf("\n"); yading@10: } yading@10: yading@10: /* yading@10: * Video decoding example yading@10: */ yading@10: yading@10: static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, yading@10: char *filename) yading@10: { yading@10: FILE *f; yading@10: int i; yading@10: yading@10: f=fopen(filename,"w"); yading@10: fprintf(f,"P5\n%d %d\n%d\n",xsize,ysize,255); yading@10: for(i=0;idata[0], frame->linesize[0], yading@10: avctx->width, avctx->height, buf); yading@10: (*frame_count)++; yading@10: } yading@10: if (pkt->data) { yading@10: pkt->size -= len; yading@10: pkt->data += len; yading@10: } yading@10: return 0; yading@10: } yading@10: yading@10: static void video_decode_example(const char *outfilename, const char *filename) yading@10: { yading@10: AVCodec *codec; yading@10: AVCodecContext *c= NULL; yading@10: int frame_count; yading@10: FILE *f; yading@10: AVFrame *frame; yading@10: uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; yading@10: AVPacket avpkt; yading@10: yading@10: av_init_packet(&avpkt); yading@10: yading@10: /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ yading@10: memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); yading@10: yading@10: printf("Decode video file %s to %s\n", filename, outfilename); yading@10: yading@10: /* find the mpeg1 video decoder */ yading@10: codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO); yading@10: if (!codec) { yading@10: fprintf(stderr, "Codec not found\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: c = avcodec_alloc_context3(codec); yading@10: if (!c) { yading@10: fprintf(stderr, "Could not allocate video codec context\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: if(codec->capabilities&CODEC_CAP_TRUNCATED) yading@10: c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ yading@10: yading@10: /* For some codecs, such as msmpeg4 and mpeg4, width and height yading@10: MUST be initialized there because this information is not yading@10: available in the bitstream. */ yading@10: yading@10: /* open it */ yading@10: if (avcodec_open2(c, codec, NULL) < 0) { yading@10: fprintf(stderr, "Could not open codec\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: f = fopen(filename, "rb"); yading@10: if (!f) { yading@10: fprintf(stderr, "Could not open %s\n", filename); yading@10: exit(1); yading@10: } yading@10: yading@10: frame = avcodec_alloc_frame(); yading@10: if (!frame) { yading@10: fprintf(stderr, "Could not allocate video frame\n"); yading@10: exit(1); yading@10: } yading@10: yading@10: frame_count = 0; yading@10: for(;;) { yading@10: avpkt.size = fread(inbuf, 1, INBUF_SIZE, f); yading@10: if (avpkt.size == 0) yading@10: break; yading@10: yading@10: /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) yading@10: and this is the only method to use them because you cannot yading@10: know the compressed data size before analysing it. yading@10: yading@10: BUT some other codecs (msmpeg4, mpeg4) are inherently frame yading@10: based, so you must call them with all the data for one yading@10: frame exactly. You must also initialize 'width' and yading@10: 'height' before initializing them. */ yading@10: yading@10: /* NOTE2: some codecs allow the raw parameters (frame size, yading@10: sample rate) to be changed at any frame. We handle this, so yading@10: you should also take care of it */ yading@10: yading@10: /* here, we use a stream based decoder (mpeg1video), so we yading@10: feed decoder and see if it could decode a frame */ yading@10: avpkt.data = inbuf; yading@10: while (avpkt.size > 0) yading@10: if (decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 0) < 0) yading@10: exit(1); yading@10: } yading@10: yading@10: /* some codecs, such as MPEG, transmit the I and P frame with a yading@10: latency of one frame. You must do the following to have a yading@10: chance to get the last frame of the video */ yading@10: avpkt.data = NULL; yading@10: avpkt.size = 0; yading@10: decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 1); yading@10: yading@10: fclose(f); yading@10: yading@10: avcodec_close(c); yading@10: av_free(c); yading@10: avcodec_free_frame(&frame); yading@10: printf("\n"); yading@10: } yading@10: yading@10: int main(int argc, char **argv) yading@10: { yading@10: const char *output_type; yading@10: yading@10: /* register all the codecs */ yading@10: avcodec_register_all(); yading@10: yading@10: if (argc < 2) { yading@10: printf("usage: %s output_type\n" yading@10: "API example program to decode/encode a media stream with libavcodec.\n" yading@10: "This program generates a synthetic stream and encodes it to a file\n" yading@10: "named test.h264, test.mp2 or test.mpg depending on output_type.\n" yading@10: "The encoded stream is then decoded and written to a raw data output.\n" yading@10: "output_type must be choosen between 'h264', 'mp2', 'mpg'.\n", yading@10: argv[0]); yading@10: return 1; yading@10: } yading@10: output_type = argv[1]; yading@10: yading@10: if (!strcmp(output_type, "h264")) { yading@10: video_encode_example("test.h264", AV_CODEC_ID_H264); yading@10: } else if (!strcmp(output_type, "mp2")) { yading@10: audio_encode_example("test.mp2"); yading@10: audio_decode_example("test.sw", "test.mp2"); yading@10: } else if (!strcmp(output_type, "mpg")) { yading@10: video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO); yading@10: video_decode_example("test%02d.pgm", "test.mpg"); yading@10: } else { yading@10: fprintf(stderr, "Invalid output type '%s', choose between 'h264', 'mp2', or 'mpg'\n", yading@10: output_type); yading@10: return 1; yading@10: } yading@10: yading@10: return 0; yading@10: }