yading@10: /*
yading@10:  * Copyright (c) 2012 Stefano Sabatini
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:  * libavformat demuxing API use example.
yading@10:  *
yading@10:  * Show how to use the libavformat and libavcodec API to demux and
yading@10:  * decode audio and video data.
yading@10:  * @example doc/examples/demuxing.c
yading@10:  */
yading@10: 
yading@10: #include <libavutil/imgutils.h>
yading@10: #include <libavutil/samplefmt.h>
yading@10: #include <libavutil/timestamp.h>
yading@10: #include <libavformat/avformat.h>
yading@10: 
yading@10: static AVFormatContext *fmt_ctx = NULL;
yading@10: static AVCodecContext *video_dec_ctx = NULL, *audio_dec_ctx;
yading@10: static AVStream *video_stream = NULL, *audio_stream = NULL;
yading@10: static const char *src_filename = NULL;
yading@10: static const char *video_dst_filename = NULL;
yading@10: static const char *audio_dst_filename = NULL;
yading@10: static FILE *video_dst_file = NULL;
yading@10: static FILE *audio_dst_file = NULL;
yading@10: 
yading@10: static uint8_t *video_dst_data[4] = {NULL};
yading@10: static int      video_dst_linesize[4];
yading@10: static int video_dst_bufsize;
yading@10: 
yading@10: static uint8_t **audio_dst_data = NULL;
yading@10: static int       audio_dst_linesize;
yading@10: static int audio_dst_bufsize;
yading@10: 
yading@10: static int video_stream_idx = -1, audio_stream_idx = -1;
yading@10: static AVFrame *frame = NULL;
yading@10: static AVPacket pkt;
yading@10: static int video_frame_count = 0;
yading@10: static int audio_frame_count = 0;
yading@10: 
yading@10: static int decode_packet(int *got_frame, int cached)
yading@10: {
yading@10:     int ret = 0;
yading@10: 
yading@10:     if (pkt.stream_index == video_stream_idx) {
yading@10:         /* decode video frame */
yading@10:         ret = avcodec_decode_video2(video_dec_ctx, frame, got_frame, &pkt);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Error decoding video frame\n");
yading@10:             return ret;
yading@10:         }
yading@10: 
yading@10:         if (*got_frame) {
yading@10:             printf("video_frame%s n:%d coded_n:%d pts:%s\n",
yading@10:                    cached ? "(cached)" : "",
yading@10:                    video_frame_count++, frame->coded_picture_number,
yading@10:                    av_ts2timestr(frame->pts, &video_dec_ctx->time_base));
yading@10: 
yading@10:             /* copy decoded frame to destination buffer:
yading@10:              * this is required since rawvideo expects non aligned data */
yading@10:             av_image_copy(video_dst_data, video_dst_linesize,
yading@10:                           (const uint8_t **)(frame->data), frame->linesize,
yading@10:                           video_dec_ctx->pix_fmt, video_dec_ctx->width, video_dec_ctx->height);
yading@10: 
yading@10:             /* write to rawvideo file */
yading@10:             fwrite(video_dst_data[0], 1, video_dst_bufsize, video_dst_file);
yading@10:         }
yading@10:     } else if (pkt.stream_index == audio_stream_idx) {
yading@10:         /* decode audio frame */
yading@10:         ret = avcodec_decode_audio4(audio_dec_ctx, frame, got_frame, &pkt);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Error decoding audio frame\n");
yading@10:             return ret;
yading@10:         }
yading@10: 
yading@10:         if (*got_frame) {
yading@10:             printf("audio_frame%s n:%d nb_samples:%d pts:%s\n",
yading@10:                    cached ? "(cached)" : "",
yading@10:                    audio_frame_count++, frame->nb_samples,
yading@10:                    av_ts2timestr(frame->pts, &audio_dec_ctx->time_base));
yading@10: 
yading@10:             ret = av_samples_alloc(audio_dst_data, &audio_dst_linesize, av_frame_get_channels(frame),
yading@10:                                    frame->nb_samples, frame->format, 1);
yading@10:             if (ret < 0) {
yading@10:                 fprintf(stderr, "Could not allocate audio buffer\n");
yading@10:                 return AVERROR(ENOMEM);
yading@10:             }
yading@10: 
yading@10:             /* TODO: extend return code of the av_samples_* functions so that this call is not needed */
yading@10:             audio_dst_bufsize =
yading@10:                 av_samples_get_buffer_size(NULL, av_frame_get_channels(frame),
yading@10:                                            frame->nb_samples, frame->format, 1);
yading@10: 
yading@10:             /* copy audio data to destination buffer:
yading@10:              * this is required since rawaudio expects non aligned data */
yading@10:             av_samples_copy(audio_dst_data, frame->data, 0, 0,
yading@10:                             frame->nb_samples, av_frame_get_channels(frame), frame->format);
yading@10: 
yading@10:             /* write to rawaudio file */
yading@10:             fwrite(audio_dst_data[0], 1, audio_dst_bufsize, audio_dst_file);
yading@10:             av_freep(&audio_dst_data[0]);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static int open_codec_context(int *stream_idx,
yading@10:                               AVFormatContext *fmt_ctx, enum AVMediaType type)
yading@10: {
yading@10:     int ret;
yading@10:     AVStream *st;
yading@10:     AVCodecContext *dec_ctx = NULL;
yading@10:     AVCodec *dec = NULL;
yading@10: 
yading@10:     ret = av_find_best_stream(fmt_ctx, type, -1, -1, NULL, 0);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Could not find %s stream in input file '%s'\n",
yading@10:                 av_get_media_type_string(type), src_filename);
yading@10:         return ret;
yading@10:     } else {
yading@10:         *stream_idx = ret;
yading@10:         st = fmt_ctx->streams[*stream_idx];
yading@10: 
yading@10:         /* find decoder for the stream */
yading@10:         dec_ctx = st->codec;
yading@10:         dec = avcodec_find_decoder(dec_ctx->codec_id);
yading@10:         if (!dec) {
yading@10:             fprintf(stderr, "Failed to find %s codec\n",
yading@10:                     av_get_media_type_string(type));
yading@10:             return ret;
yading@10:         }
yading@10: 
yading@10:         if ((ret = avcodec_open2(dec_ctx, dec, NULL)) < 0) {
yading@10:             fprintf(stderr, "Failed to open %s codec\n",
yading@10:                     av_get_media_type_string(type));
yading@10:             return ret;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int get_format_from_sample_fmt(const char **fmt,
yading@10:                                       enum AVSampleFormat sample_fmt)
yading@10: {
yading@10:     int i;
yading@10:     struct sample_fmt_entry {
yading@10:         enum AVSampleFormat sample_fmt; const char *fmt_be, *fmt_le;
yading@10:     } sample_fmt_entries[] = {
yading@10:         { AV_SAMPLE_FMT_U8,  "u8",    "u8"    },
yading@10:         { AV_SAMPLE_FMT_S16, "s16be", "s16le" },
yading@10:         { AV_SAMPLE_FMT_S32, "s32be", "s32le" },
yading@10:         { AV_SAMPLE_FMT_FLT, "f32be", "f32le" },
yading@10:         { AV_SAMPLE_FMT_DBL, "f64be", "f64le" },
yading@10:     };
yading@10:     *fmt = NULL;
yading@10: 
yading@10:     for (i = 0; i < FF_ARRAY_ELEMS(sample_fmt_entries); i++) {
yading@10:         struct sample_fmt_entry *entry = &sample_fmt_entries[i];
yading@10:         if (sample_fmt == entry->sample_fmt) {
yading@10:             *fmt = AV_NE(entry->fmt_be, entry->fmt_le);
yading@10:             return 0;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     fprintf(stderr,
yading@10:             "sample format %s is not supported as output format\n",
yading@10:             av_get_sample_fmt_name(sample_fmt));
yading@10:     return -1;
yading@10: }
yading@10: 
yading@10: int main (int argc, char **argv)
yading@10: {
yading@10:     int ret = 0, got_frame;
yading@10: 
yading@10:     if (argc != 4) {
yading@10:         fprintf(stderr, "usage: %s input_file video_output_file audio_output_file\n"
yading@10:                 "API example program to show how to read frames from an input file.\n"
yading@10:                 "This program reads frames from a file, decodes them, and writes decoded\n"
yading@10:                 "video frames to a rawvideo file named video_output_file, and decoded\n"
yading@10:                 "audio frames to a rawaudio file named audio_output_file.\n"
yading@10:                 "\n", argv[0]);
yading@10:         exit(1);
yading@10:     }
yading@10:     src_filename = argv[1];
yading@10:     video_dst_filename = argv[2];
yading@10:     audio_dst_filename = argv[3];
yading@10: 
yading@10:     /* register all formats and codecs */
yading@10:     av_register_all();
yading@10: 
yading@10:     /* open input file, and allocate format context */
yading@10:     if (avformat_open_input(&fmt_ctx, src_filename, NULL, NULL) < 0) {
yading@10:         fprintf(stderr, "Could not open source file %s\n", src_filename);
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     /* retrieve stream information */
yading@10:     if (avformat_find_stream_info(fmt_ctx, NULL) < 0) {
yading@10:         fprintf(stderr, "Could not find stream information\n");
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     if (open_codec_context(&video_stream_idx, fmt_ctx, AVMEDIA_TYPE_VIDEO) >= 0) {
yading@10:         video_stream = fmt_ctx->streams[video_stream_idx];
yading@10:         video_dec_ctx = video_stream->codec;
yading@10: 
yading@10:         video_dst_file = fopen(video_dst_filename, "wb");
yading@10:         if (!video_dst_file) {
yading@10:             fprintf(stderr, "Could not open destination file %s\n", video_dst_filename);
yading@10:             ret = 1;
yading@10:             goto end;
yading@10:         }
yading@10: 
yading@10:         /* allocate image where the decoded image will be put */
yading@10:         ret = av_image_alloc(video_dst_data, video_dst_linesize,
yading@10:                              video_dec_ctx->width, video_dec_ctx->height,
yading@10:                              video_dec_ctx->pix_fmt, 1);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Could not allocate raw video buffer\n");
yading@10:             goto end;
yading@10:         }
yading@10:         video_dst_bufsize = ret;
yading@10:     }
yading@10: 
yading@10:     if (open_codec_context(&audio_stream_idx, fmt_ctx, AVMEDIA_TYPE_AUDIO) >= 0) {
yading@10:         int nb_planes;
yading@10: 
yading@10:         audio_stream = fmt_ctx->streams[audio_stream_idx];
yading@10:         audio_dec_ctx = audio_stream->codec;
yading@10:         audio_dst_file = fopen(audio_dst_filename, "wb");
yading@10:         if (!audio_dst_file) {
yading@10:             fprintf(stderr, "Could not open destination file %s\n", video_dst_filename);
yading@10:             ret = 1;
yading@10:             goto end;
yading@10:         }
yading@10: 
yading@10:         nb_planes = av_sample_fmt_is_planar(audio_dec_ctx->sample_fmt) ?
yading@10:             audio_dec_ctx->channels : 1;
yading@10:         audio_dst_data = av_mallocz(sizeof(uint8_t *) * nb_planes);
yading@10:         if (!audio_dst_data) {
yading@10:             fprintf(stderr, "Could not allocate audio data buffers\n");
yading@10:             ret = AVERROR(ENOMEM);
yading@10:             goto end;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     /* dump input information to stderr */
yading@10:     av_dump_format(fmt_ctx, 0, src_filename, 0);
yading@10: 
yading@10:     if (!audio_stream && !video_stream) {
yading@10:         fprintf(stderr, "Could not find audio or video stream in the input, aborting\n");
yading@10:         ret = 1;
yading@10:         goto end;
yading@10:     }
yading@10: 
yading@10:     frame = avcodec_alloc_frame();
yading@10:     if (!frame) {
yading@10:         fprintf(stderr, "Could not allocate frame\n");
yading@10:         ret = AVERROR(ENOMEM);
yading@10:         goto end;
yading@10:     }
yading@10: 
yading@10:     /* initialize packet, set data to NULL, let the demuxer fill it */
yading@10:     av_init_packet(&pkt);
yading@10:     pkt.data = NULL;
yading@10:     pkt.size = 0;
yading@10: 
yading@10:     if (video_stream)
yading@10:         printf("Demuxing video from file '%s' into '%s'\n", src_filename, video_dst_filename);
yading@10:     if (audio_stream)
yading@10:         printf("Demuxing audio from file '%s' into '%s'\n", src_filename, audio_dst_filename);
yading@10: 
yading@10:     /* read frames from the file */
yading@10:     while (av_read_frame(fmt_ctx, &pkt) >= 0) {
yading@10:         decode_packet(&got_frame, 0);
yading@10:         av_free_packet(&pkt);
yading@10:     }
yading@10: 
yading@10:     /* flush cached frames */
yading@10:     pkt.data = NULL;
yading@10:     pkt.size = 0;
yading@10:     do {
yading@10:         decode_packet(&got_frame, 1);
yading@10:     } while (got_frame);
yading@10: 
yading@10:     printf("Demuxing succeeded.\n");
yading@10: 
yading@10:     if (video_stream) {
yading@10:         printf("Play the output video file with the command:\n"
yading@10:                "ffplay -f rawvideo -pix_fmt %s -video_size %dx%d %s\n",
yading@10:                av_get_pix_fmt_name(video_dec_ctx->pix_fmt), video_dec_ctx->width, video_dec_ctx->height,
yading@10:                video_dst_filename);
yading@10:     }
yading@10: 
yading@10:     if (audio_stream) {
yading@10:         const char *fmt;
yading@10: 
yading@10:         if ((ret = get_format_from_sample_fmt(&fmt, audio_dec_ctx->sample_fmt)) < 0)
yading@10:             goto end;
yading@10:         printf("Play the output audio file with the command:\n"
yading@10:                "ffplay -f %s -ac %d -ar %d %s\n",
yading@10:                fmt, audio_dec_ctx->channels, audio_dec_ctx->sample_rate,
yading@10:                audio_dst_filename);
yading@10:     }
yading@10: 
yading@10: end:
yading@10:     if (video_dec_ctx)
yading@10:         avcodec_close(video_dec_ctx);
yading@10:     if (audio_dec_ctx)
yading@10:         avcodec_close(audio_dec_ctx);
yading@10:     avformat_close_input(&fmt_ctx);
yading@10:     if (video_dst_file)
yading@10:         fclose(video_dst_file);
yading@10:     if (audio_dst_file)
yading@10:         fclose(audio_dst_file);
yading@10:     av_free(frame);
yading@10:     av_free(video_dst_data[0]);
yading@10:     av_free(audio_dst_data);
yading@10: 
yading@10:     return ret < 0;
yading@10: }