| /* |
| * Copyright (c) 2001 Fabrice Bellard |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| /** |
| * @file |
| * libavcodec API use example. |
| * |
| * Note that libavcodec only handles codecs (mpeg, mpeg4, etc...), |
| * not file formats (avi, vob, mp4, mov, mkv, mxf, flv, mpegts, mpegps, etc...). See library 'libavformat' for the |
| * format handling |
| * @example doc/examples/decoding_encoding.c |
| */ |
| |
| #include <math.h> |
| |
| #include <libavutil/opt.h> |
| #include <libavcodec/avcodec.h> |
| #include <libavutil/channel_layout.h> |
| #include <libavutil/common.h> |
| #include <libavutil/imgutils.h> |
| #include <libavutil/mathematics.h> |
| #include <libavutil/samplefmt.h> |
| |
| #define INBUF_SIZE 4096 |
| #define AUDIO_INBUF_SIZE 20480 |
| #define AUDIO_REFILL_THRESH 4096 |
| |
| /* check that a given sample format is supported by the encoder */ |
| static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt) |
| { |
| const enum AVSampleFormat *p = codec->sample_fmts; |
| |
| while (*p != AV_SAMPLE_FMT_NONE) { |
| if (*p == sample_fmt) |
| return 1; |
| p++; |
| } |
| return 0; |
| } |
| |
| /* just pick the highest supported samplerate */ |
| static int select_sample_rate(AVCodec *codec) |
| { |
| const int *p; |
| int best_samplerate = 0; |
| |
| if (!codec->supported_samplerates) |
| return 44100; |
| |
| p = codec->supported_samplerates; |
| while (*p) { |
| best_samplerate = FFMAX(*p, best_samplerate); |
| p++; |
| } |
| return best_samplerate; |
| } |
| |
| /* select layout with the highest channel count */ |
| static int select_channel_layout(AVCodec *codec) |
| { |
| const uint64_t *p; |
| uint64_t best_ch_layout = 0; |
| int best_nb_channels = 0; |
| |
| if (!codec->channel_layouts) |
| return AV_CH_LAYOUT_STEREO; |
| |
| p = codec->channel_layouts; |
| while (*p) { |
| int nb_channels = av_get_channel_layout_nb_channels(*p); |
| |
| if (nb_channels > best_nb_channels) { |
| best_ch_layout = *p; |
| best_nb_channels = nb_channels; |
| } |
| p++; |
| } |
| return best_ch_layout; |
| } |
| |
| /* |
| * Audio encoding example |
| */ |
| static void audio_encode_example(const char *filename) |
| { |
| AVCodec *codec; |
| AVCodecContext *c= NULL; |
| AVFrame *frame; |
| AVPacket pkt; |
| int i, j, k, ret, got_output; |
| int buffer_size; |
| FILE *f; |
| uint16_t *samples; |
| float t, tincr; |
| |
| printf("Encode audio file %s\n", filename); |
| |
| /* find the MP2 encoder */ |
| codec = avcodec_find_encoder(AV_CODEC_ID_MP2); |
| if (!codec) { |
| fprintf(stderr, "Codec not found\n"); |
| exit(1); |
| } |
| |
| c = avcodec_alloc_context3(codec); |
| if (!c) { |
| fprintf(stderr, "Could not allocate audio codec context\n"); |
| exit(1); |
| } |
| |
| /* put sample parameters */ |
| c->bit_rate = 64000; |
| |
| /* check that the encoder supports s16 pcm input */ |
| c->sample_fmt = AV_SAMPLE_FMT_S16; |
| if (!check_sample_fmt(codec, c->sample_fmt)) { |
| fprintf(stderr, "Encoder does not support sample format %s", |
| av_get_sample_fmt_name(c->sample_fmt)); |
| exit(1); |
| } |
| |
| /* select other audio parameters supported by the encoder */ |
| c->sample_rate = select_sample_rate(codec); |
| c->channel_layout = select_channel_layout(codec); |
| c->channels = av_get_channel_layout_nb_channels(c->channel_layout); |
| |
| /* open it */ |
| if (avcodec_open2(c, codec, NULL) < 0) { |
| fprintf(stderr, "Could not open codec\n"); |
| exit(1); |
| } |
| |
| f = fopen(filename, "wb"); |
| if (!f) { |
| fprintf(stderr, "Could not open %s\n", filename); |
| exit(1); |
| } |
| |
| /* frame containing input raw audio */ |
| frame = avcodec_alloc_frame(); |
| if (!frame) { |
| fprintf(stderr, "Could not allocate audio frame\n"); |
| exit(1); |
| } |
| |
| frame->nb_samples = c->frame_size; |
| frame->format = c->sample_fmt; |
| frame->channel_layout = c->channel_layout; |
| |
| /* the codec gives us the frame size, in samples, |
| * we calculate the size of the samples buffer in bytes */ |
| buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size, |
| c->sample_fmt, 0); |
| samples = av_malloc(buffer_size); |
| if (!samples) { |
| fprintf(stderr, "Could not allocate %d bytes for samples buffer\n", |
| buffer_size); |
| exit(1); |
| } |
| /* setup the data pointers in the AVFrame */ |
| ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt, |
| (const uint8_t*)samples, buffer_size, 0); |
| if (ret < 0) { |
| fprintf(stderr, "Could not setup audio frame\n"); |
| exit(1); |
| } |
| |
| /* encode a single tone sound */ |
| t = 0; |
| tincr = 2 * M_PI * 440.0 / c->sample_rate; |
| for(i=0;i<200;i++) { |
| av_init_packet(&pkt); |
| pkt.data = NULL; // packet data will be allocated by the encoder |
| pkt.size = 0; |
| |
| for (j = 0; j < c->frame_size; j++) { |
| samples[2*j] = (int)(sin(t) * 10000); |
| |
| for (k = 1; k < c->channels; k++) |
| samples[2*j + k] = samples[2*j]; |
| t += tincr; |
| } |
| /* encode the samples */ |
| ret = avcodec_encode_audio2(c, &pkt, frame, &got_output); |
| if (ret < 0) { |
| fprintf(stderr, "Error encoding audio frame\n"); |
| exit(1); |
| } |
| if (got_output) { |
| fwrite(pkt.data, 1, pkt.size, f); |
| av_free_packet(&pkt); |
| } |
| } |
| |
| /* get the delayed frames */ |
| for (got_output = 1; got_output; i++) { |
| ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output); |
| if (ret < 0) { |
| fprintf(stderr, "Error encoding frame\n"); |
| exit(1); |
| } |
| |
| if (got_output) { |
| fwrite(pkt.data, 1, pkt.size, f); |
| av_free_packet(&pkt); |
| } |
| } |
| fclose(f); |
| |
| av_freep(&samples); |
| avcodec_free_frame(&frame); |
| avcodec_close(c); |
| av_free(c); |
| } |
| |
| /* |
| * Audio decoding. |
| */ |
| static void audio_decode_example(const char *outfilename, const char *filename) |
| { |
| AVCodec *codec; |
| AVCodecContext *c= NULL; |
| int len; |
| FILE *f, *outfile; |
| uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; |
| AVPacket avpkt; |
| AVFrame *decoded_frame = NULL; |
| |
| av_init_packet(&avpkt); |
| |
| printf("Decode audio file %s to %s\n", filename, outfilename); |
| |
| /* find the mpeg audio decoder */ |
| codec = avcodec_find_decoder(AV_CODEC_ID_MP2); |
| if (!codec) { |
| fprintf(stderr, "Codec not found\n"); |
| exit(1); |
| } |
| |
| c = avcodec_alloc_context3(codec); |
| if (!c) { |
| fprintf(stderr, "Could not allocate audio codec context\n"); |
| exit(1); |
| } |
| |
| /* open it */ |
| if (avcodec_open2(c, codec, NULL) < 0) { |
| fprintf(stderr, "Could not open codec\n"); |
| exit(1); |
| } |
| |
| f = fopen(filename, "rb"); |
| if (!f) { |
| fprintf(stderr, "Could not open %s\n", filename); |
| exit(1); |
| } |
| outfile = fopen(outfilename, "wb"); |
| if (!outfile) { |
| av_free(c); |
| exit(1); |
| } |
| |
| /* decode until eof */ |
| avpkt.data = inbuf; |
| avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f); |
| |
| while (avpkt.size > 0) { |
| int got_frame = 0; |
| |
| if (!decoded_frame) { |
| if (!(decoded_frame = avcodec_alloc_frame())) { |
| fprintf(stderr, "Could not allocate audio frame\n"); |
| exit(1); |
| } |
| } else |
| avcodec_get_frame_defaults(decoded_frame); |
| |
| len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt); |
| if (len < 0) { |
| fprintf(stderr, "Error while decoding\n"); |
| exit(1); |
| } |
| if (got_frame) { |
| /* if a frame has been decoded, output it */ |
| int data_size = av_samples_get_buffer_size(NULL, c->channels, |
| decoded_frame->nb_samples, |
| c->sample_fmt, 1); |
| fwrite(decoded_frame->data[0], 1, data_size, outfile); |
| } |
| avpkt.size -= len; |
| avpkt.data += len; |
| avpkt.dts = |
| avpkt.pts = AV_NOPTS_VALUE; |
| if (avpkt.size < AUDIO_REFILL_THRESH) { |
| /* Refill the input buffer, to avoid trying to decode |
| * incomplete frames. Instead of this, one could also use |
| * a parser, or use a proper container format through |
| * libavformat. */ |
| memmove(inbuf, avpkt.data, avpkt.size); |
| avpkt.data = inbuf; |
| len = fread(avpkt.data + avpkt.size, 1, |
| AUDIO_INBUF_SIZE - avpkt.size, f); |
| if (len > 0) |
| avpkt.size += len; |
| } |
| } |
| |
| fclose(outfile); |
| fclose(f); |
| |
| avcodec_close(c); |
| av_free(c); |
| avcodec_free_frame(&decoded_frame); |
| } |
| |
| /* |
| * Video encoding example |
| */ |
| static void video_encode_example(const char *filename, int codec_id) |
| { |
| AVCodec *codec; |
| AVCodecContext *c= NULL; |
| int i, ret, x, y, got_output; |
| FILE *f; |
| AVFrame *frame; |
| AVPacket pkt; |
| uint8_t endcode[] = { 0, 0, 1, 0xb7 }; |
| |
| printf("Encode video file %s\n", filename); |
| |
| /* find the mpeg1 video encoder */ |
| codec = avcodec_find_encoder(codec_id); |
| if (!codec) { |
| fprintf(stderr, "Codec not found\n"); |
| exit(1); |
| } |
| |
| c = avcodec_alloc_context3(codec); |
| if (!c) { |
| fprintf(stderr, "Could not allocate video codec context\n"); |
| exit(1); |
| } |
| |
| /* put sample parameters */ |
| c->bit_rate = 400000; |
| /* resolution must be a multiple of two */ |
| c->width = 352; |
| c->height = 288; |
| /* frames per second */ |
| c->time_base= (AVRational){1,25}; |
| c->gop_size = 10; /* emit one intra frame every ten frames */ |
| c->max_b_frames=1; |
| c->pix_fmt = AV_PIX_FMT_YUV420P; |
| |
| if(codec_id == AV_CODEC_ID_H264) |
| av_opt_set(c->priv_data, "preset", "slow", 0); |
| |
| /* open it */ |
| if (avcodec_open2(c, codec, NULL) < 0) { |
| fprintf(stderr, "Could not open codec\n"); |
| exit(1); |
| } |
| |
| f = fopen(filename, "wb"); |
| if (!f) { |
| fprintf(stderr, "Could not open %s\n", filename); |
| exit(1); |
| } |
| |
| frame = avcodec_alloc_frame(); |
| if (!frame) { |
| fprintf(stderr, "Could not allocate video frame\n"); |
| exit(1); |
| } |
| frame->format = c->pix_fmt; |
| frame->width = c->width; |
| frame->height = c->height; |
| |
| /* the image can be allocated by any means and av_image_alloc() is |
| * just the most convenient way if av_malloc() is to be used */ |
| ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, |
| c->pix_fmt, 32); |
| if (ret < 0) { |
| fprintf(stderr, "Could not allocate raw picture buffer\n"); |
| exit(1); |
| } |
| |
| /* encode 1 second of video */ |
| for(i=0;i<25;i++) { |
| av_init_packet(&pkt); |
| pkt.data = NULL; // packet data will be allocated by the encoder |
| pkt.size = 0; |
| |
| fflush(stdout); |
| /* prepare a dummy image */ |
| /* Y */ |
| for(y=0;y<c->height;y++) { |
| for(x=0;x<c->width;x++) { |
| frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3; |
| } |
| } |
| |
| /* Cb and Cr */ |
| for(y=0;y<c->height/2;y++) { |
| for(x=0;x<c->width/2;x++) { |
| frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2; |
| frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5; |
| } |
| } |
| |
| frame->pts = i; |
| |
| /* encode the image */ |
| ret = avcodec_encode_video2(c, &pkt, frame, &got_output); |
| if (ret < 0) { |
| fprintf(stderr, "Error encoding frame\n"); |
| exit(1); |
| } |
| |
| if (got_output) { |
| printf("Write frame %3d (size=%5d)\n", i, pkt.size); |
| fwrite(pkt.data, 1, pkt.size, f); |
| av_free_packet(&pkt); |
| } |
| } |
| |
| /* get the delayed frames */ |
| for (got_output = 1; got_output; i++) { |
| fflush(stdout); |
| |
| ret = avcodec_encode_video2(c, &pkt, NULL, &got_output); |
| if (ret < 0) { |
| fprintf(stderr, "Error encoding frame\n"); |
| exit(1); |
| } |
| |
| if (got_output) { |
| printf("Write frame %3d (size=%5d)\n", i, pkt.size); |
| fwrite(pkt.data, 1, pkt.size, f); |
| av_free_packet(&pkt); |
| } |
| } |
| |
| /* add sequence end code to have a real mpeg file */ |
| fwrite(endcode, 1, sizeof(endcode), f); |
| fclose(f); |
| |
| avcodec_close(c); |
| av_free(c); |
| av_freep(&frame->data[0]); |
| avcodec_free_frame(&frame); |
| printf("\n"); |
| } |
| |
| /* |
| * Video decoding example |
| */ |
| |
| static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, |
| char *filename) |
| { |
| FILE *f; |
| int i; |
| |
| f=fopen(filename,"w"); |
| fprintf(f,"P5\n%d %d\n%d\n",xsize,ysize,255); |
| for(i=0;i<ysize;i++) |
| fwrite(buf + i * wrap,1,xsize,f); |
| fclose(f); |
| } |
| |
| static int decode_write_frame(const char *outfilename, AVCodecContext *avctx, |
| AVFrame *frame, int *frame_count, AVPacket *pkt, int last) |
| { |
| int len, got_frame; |
| char buf[1024]; |
| |
| len = avcodec_decode_video2(avctx, frame, &got_frame, pkt); |
| if (len < 0) { |
| fprintf(stderr, "Error while decoding frame %d\n", *frame_count); |
| return len; |
| } |
| if (got_frame) { |
| printf("Saving %sframe %3d\n", last ? "last " : "", *frame_count); |
| fflush(stdout); |
| |
| /* the picture is allocated by the decoder, no need to free it */ |
| snprintf(buf, sizeof(buf), outfilename, *frame_count); |
| pgm_save(frame->data[0], frame->linesize[0], |
| avctx->width, avctx->height, buf); |
| (*frame_count)++; |
| } |
| if (pkt->data) { |
| pkt->size -= len; |
| pkt->data += len; |
| } |
| return 0; |
| } |
| |
| static void video_decode_example(const char *outfilename, const char *filename) |
| { |
| AVCodec *codec; |
| AVCodecContext *c= NULL; |
| int frame_count; |
| FILE *f; |
| AVFrame *frame; |
| uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; |
| AVPacket avpkt; |
| |
| av_init_packet(&avpkt); |
| |
| /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ |
| memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); |
| |
| printf("Decode video file %s to %s\n", filename, outfilename); |
| |
| /* find the mpeg1 video decoder */ |
| codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO); |
| if (!codec) { |
| fprintf(stderr, "Codec not found\n"); |
| exit(1); |
| } |
| |
| c = avcodec_alloc_context3(codec); |
| if (!c) { |
| fprintf(stderr, "Could not allocate video codec context\n"); |
| exit(1); |
| } |
| |
| if(codec->capabilities&CODEC_CAP_TRUNCATED) |
| c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ |
| |
| /* For some codecs, such as msmpeg4 and mpeg4, width and height |
| MUST be initialized there because this information is not |
| available in the bitstream. */ |
| |
| /* open it */ |
| if (avcodec_open2(c, codec, NULL) < 0) { |
| fprintf(stderr, "Could not open codec\n"); |
| exit(1); |
| } |
| |
| f = fopen(filename, "rb"); |
| if (!f) { |
| fprintf(stderr, "Could not open %s\n", filename); |
| exit(1); |
| } |
| |
| frame = avcodec_alloc_frame(); |
| if (!frame) { |
| fprintf(stderr, "Could not allocate video frame\n"); |
| exit(1); |
| } |
| |
| frame_count = 0; |
| for(;;) { |
| avpkt.size = fread(inbuf, 1, INBUF_SIZE, f); |
| if (avpkt.size == 0) |
| break; |
| |
| /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) |
| and this is the only method to use them because you cannot |
| know the compressed data size before analysing it. |
| |
| BUT some other codecs (msmpeg4, mpeg4) are inherently frame |
| based, so you must call them with all the data for one |
| frame exactly. You must also initialize 'width' and |
| 'height' before initializing them. */ |
| |
| /* NOTE2: some codecs allow the raw parameters (frame size, |
| sample rate) to be changed at any frame. We handle this, so |
| you should also take care of it */ |
| |
| /* here, we use a stream based decoder (mpeg1video), so we |
| feed decoder and see if it could decode a frame */ |
| avpkt.data = inbuf; |
| while (avpkt.size > 0) |
| if (decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 0) < 0) |
| exit(1); |
| } |
| |
| /* some codecs, such as MPEG, transmit the I and P frame with a |
| latency of one frame. You must do the following to have a |
| chance to get the last frame of the video */ |
| avpkt.data = NULL; |
| avpkt.size = 0; |
| decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 1); |
| |
| fclose(f); |
| |
| avcodec_close(c); |
| av_free(c); |
| avcodec_free_frame(&frame); |
| printf("\n"); |
| } |
| |
| int main(int argc, char **argv) |
| { |
| const char *output_type; |
| |
| /* register all the codecs */ |
| avcodec_register_all(); |
| |
| if (argc < 2) { |
| printf("usage: %s output_type\n" |
| "API example program to decode/encode a media stream with libavcodec.\n" |
| "This program generates a synthetic stream and encodes it to a file\n" |
| "named test.h264, test.mp2 or test.mpg depending on output_type.\n" |
| "The encoded stream is then decoded and written to a raw data output.\n" |
| "output_type must be choosen between 'h264', 'mp2', 'mpg'.\n", |
| argv[0]); |
| return 1; |
| } |
| output_type = argv[1]; |
| |
| if (!strcmp(output_type, "h264")) { |
| video_encode_example("test.h264", AV_CODEC_ID_H264); |
| } else if (!strcmp(output_type, "mp2")) { |
| audio_encode_example("test.mp2"); |
| audio_decode_example("test.sw", "test.mp2"); |
| } else if (!strcmp(output_type, "mpg")) { |
| video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO); |
| video_decode_example("test%02d.pgm", "test.mpg"); |
| } else { |
| fprintf(stderr, "Invalid output type '%s', choose between 'h264', 'mp2', or 'mpg'\n", |
| output_type); |
| return 1; |
| } |
| |
| return 0; |
| } |