| /* |
| * Copyright (c) 2012 Stefano Sabatini |
| * |
| * 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 |
| * Demuxing and decoding example. |
| * |
| * Show how to use the libavformat and libavcodec API to demux and |
| * decode audio and video data. |
| * @example demuxing_decoding.c |
| */ |
| |
| #include <libavutil/imgutils.h> |
| #include <libavutil/samplefmt.h> |
| #include <libavutil/timestamp.h> |
| #include <libavformat/avformat.h> |
| |
| static AVFormatContext *fmt_ctx = NULL; |
| static AVCodecContext *video_dec_ctx = NULL, *audio_dec_ctx; |
| static int width, height; |
| static enum AVPixelFormat pix_fmt; |
| static AVStream *video_stream = NULL, *audio_stream = NULL; |
| static const char *src_filename = NULL; |
| static const char *video_dst_filename = NULL; |
| static const char *audio_dst_filename = NULL; |
| static FILE *video_dst_file = NULL; |
| static FILE *audio_dst_file = NULL; |
| |
| static uint8_t *video_dst_data[4] = {NULL}; |
| static int video_dst_linesize[4]; |
| static int video_dst_bufsize; |
| |
| static int video_stream_idx = -1, audio_stream_idx = -1; |
| static AVFrame *frame = NULL; |
| static AVPacket pkt; |
| static int video_frame_count = 0; |
| static int audio_frame_count = 0; |
| |
| /* Enable or disable frame reference counting. You are not supposed to support |
| * both paths in your application but pick the one most appropriate to your |
| * needs. Look for the use of refcount in this example to see what are the |
| * differences of API usage between them. */ |
| static int refcount = 0; |
| |
| static int decode_packet(int *got_frame, int cached) |
| { |
| int ret = 0; |
| int decoded = pkt.size; |
| |
| *got_frame = 0; |
| |
| if (pkt.stream_index == video_stream_idx) { |
| /* decode video frame */ |
| ret = avcodec_decode_video2(video_dec_ctx, frame, got_frame, &pkt); |
| if (ret < 0) { |
| fprintf(stderr, "Error decoding video frame (%s)\n", av_err2str(ret)); |
| return ret; |
| } |
| |
| if (*got_frame) { |
| |
| if (frame->width != width || frame->height != height || |
| frame->format != pix_fmt) { |
| /* To handle this change, one could call av_image_alloc again and |
| * decode the following frames into another rawvideo file. */ |
| fprintf(stderr, "Error: Width, height and pixel format have to be " |
| "constant in a rawvideo file, but the width, height or " |
| "pixel format of the input video changed:\n" |
| "old: width = %d, height = %d, format = %s\n" |
| "new: width = %d, height = %d, format = %s\n", |
| width, height, av_get_pix_fmt_name(pix_fmt), |
| frame->width, frame->height, |
| av_get_pix_fmt_name(frame->format)); |
| return -1; |
| } |
| |
| printf("video_frame%s n:%d coded_n:%d\n", |
| cached ? "(cached)" : "", |
| video_frame_count++, frame->coded_picture_number); |
| |
| /* copy decoded frame to destination buffer: |
| * this is required since rawvideo expects non aligned data */ |
| av_image_copy(video_dst_data, video_dst_linesize, |
| (const uint8_t **)(frame->data), frame->linesize, |
| pix_fmt, width, height); |
| |
| /* write to rawvideo file */ |
| fwrite(video_dst_data[0], 1, video_dst_bufsize, video_dst_file); |
| } |
| } else if (pkt.stream_index == audio_stream_idx) { |
| /* decode audio frame */ |
| ret = avcodec_decode_audio4(audio_dec_ctx, frame, got_frame, &pkt); |
| if (ret < 0) { |
| fprintf(stderr, "Error decoding audio frame (%s)\n", av_err2str(ret)); |
| return ret; |
| } |
| /* Some audio decoders decode only part of the packet, and have to be |
| * called again with the remainder of the packet data. |
| * Sample: fate-suite/lossless-audio/luckynight-partial.shn |
| * Also, some decoders might over-read the packet. */ |
| decoded = FFMIN(ret, pkt.size); |
| |
| if (*got_frame) { |
| size_t unpadded_linesize = frame->nb_samples * av_get_bytes_per_sample(frame->format); |
| printf("audio_frame%s n:%d nb_samples:%d pts:%s\n", |
| cached ? "(cached)" : "", |
| audio_frame_count++, frame->nb_samples, |
| av_ts2timestr(frame->pts, &audio_dec_ctx->time_base)); |
| |
| /* Write the raw audio data samples of the first plane. This works |
| * fine for packed formats (e.g. AV_SAMPLE_FMT_S16). However, |
| * most audio decoders output planar audio, which uses a separate |
| * plane of audio samples for each channel (e.g. AV_SAMPLE_FMT_S16P). |
| * In other words, this code will write only the first audio channel |
| * in these cases. |
| * You should use libswresample or libavfilter to convert the frame |
| * to packed data. */ |
| fwrite(frame->extended_data[0], 1, unpadded_linesize, audio_dst_file); |
| } |
| } |
| |
| /* If we use frame reference counting, we own the data and need |
| * to de-reference it when we don't use it anymore */ |
| if (*got_frame && refcount) |
| av_frame_unref(frame); |
| |
| return decoded; |
| } |
| |
| static int open_codec_context(int *stream_idx, |
| AVCodecContext **dec_ctx, AVFormatContext *fmt_ctx, enum AVMediaType type) |
| { |
| int ret, stream_index; |
| AVStream *st; |
| AVCodec *dec = NULL; |
| AVDictionary *opts = NULL; |
| |
| ret = av_find_best_stream(fmt_ctx, type, -1, -1, NULL, 0); |
| if (ret < 0) { |
| fprintf(stderr, "Could not find %s stream in input file '%s'\n", |
| av_get_media_type_string(type), src_filename); |
| return ret; |
| } else { |
| stream_index = ret; |
| st = fmt_ctx->streams[stream_index]; |
| |
| /* find decoder for the stream */ |
| dec = avcodec_find_decoder(st->codecpar->codec_id); |
| if (!dec) { |
| fprintf(stderr, "Failed to find %s codec\n", |
| av_get_media_type_string(type)); |
| return AVERROR(EINVAL); |
| } |
| |
| /* Allocate a codec context for the decoder */ |
| *dec_ctx = avcodec_alloc_context3(dec); |
| if (!*dec_ctx) { |
| fprintf(stderr, "Failed to allocate the %s codec context\n", |
| av_get_media_type_string(type)); |
| return AVERROR(ENOMEM); |
| } |
| |
| /* Copy codec parameters from input stream to output codec context */ |
| if ((ret = avcodec_parameters_to_context(*dec_ctx, st->codecpar)) < 0) { |
| fprintf(stderr, "Failed to copy %s codec parameters to decoder context\n", |
| av_get_media_type_string(type)); |
| return ret; |
| } |
| |
| /* Init the decoders, with or without reference counting */ |
| av_dict_set(&opts, "refcounted_frames", refcount ? "1" : "0", 0); |
| if ((ret = avcodec_open2(*dec_ctx, dec, &opts)) < 0) { |
| fprintf(stderr, "Failed to open %s codec\n", |
| av_get_media_type_string(type)); |
| return ret; |
| } |
| *stream_idx = stream_index; |
| } |
| |
| return 0; |
| } |
| |
| static int get_format_from_sample_fmt(const char **fmt, |
| enum AVSampleFormat sample_fmt) |
| { |
| int i; |
| struct sample_fmt_entry { |
| enum AVSampleFormat sample_fmt; const char *fmt_be, *fmt_le; |
| } sample_fmt_entries[] = { |
| { AV_SAMPLE_FMT_U8, "u8", "u8" }, |
| { AV_SAMPLE_FMT_S16, "s16be", "s16le" }, |
| { AV_SAMPLE_FMT_S32, "s32be", "s32le" }, |
| { AV_SAMPLE_FMT_FLT, "f32be", "f32le" }, |
| { AV_SAMPLE_FMT_DBL, "f64be", "f64le" }, |
| }; |
| *fmt = NULL; |
| |
| for (i = 0; i < FF_ARRAY_ELEMS(sample_fmt_entries); i++) { |
| struct sample_fmt_entry *entry = &sample_fmt_entries[i]; |
| if (sample_fmt == entry->sample_fmt) { |
| *fmt = AV_NE(entry->fmt_be, entry->fmt_le); |
| return 0; |
| } |
| } |
| |
| fprintf(stderr, |
| "sample format %s is not supported as output format\n", |
| av_get_sample_fmt_name(sample_fmt)); |
| return -1; |
| } |
| |
| int main (int argc, char **argv) |
| { |
| int ret = 0, got_frame; |
| |
| if (argc != 4 && argc != 5) { |
| fprintf(stderr, "usage: %s [-refcount] input_file video_output_file audio_output_file\n" |
| "API example program to show how to read frames from an input file.\n" |
| "This program reads frames from a file, decodes them, and writes decoded\n" |
| "video frames to a rawvideo file named video_output_file, and decoded\n" |
| "audio frames to a rawaudio file named audio_output_file.\n\n" |
| "If the -refcount option is specified, the program use the\n" |
| "reference counting frame system which allows keeping a copy of\n" |
| "the data for longer than one decode call.\n" |
| "\n", argv[0]); |
| exit(1); |
| } |
| if (argc == 5 && !strcmp(argv[1], "-refcount")) { |
| refcount = 1; |
| argv++; |
| } |
| src_filename = argv[1]; |
| video_dst_filename = argv[2]; |
| audio_dst_filename = argv[3]; |
| |
| /* register all formats and codecs */ |
| av_register_all(); |
| |
| /* open input file, and allocate format context */ |
| if (avformat_open_input(&fmt_ctx, src_filename, NULL, NULL) < 0) { |
| fprintf(stderr, "Could not open source file %s\n", src_filename); |
| exit(1); |
| } |
| |
| /* retrieve stream information */ |
| if (avformat_find_stream_info(fmt_ctx, NULL) < 0) { |
| fprintf(stderr, "Could not find stream information\n"); |
| exit(1); |
| } |
| |
| if (open_codec_context(&video_stream_idx, &video_dec_ctx, fmt_ctx, AVMEDIA_TYPE_VIDEO) >= 0) { |
| video_stream = fmt_ctx->streams[video_stream_idx]; |
| |
| video_dst_file = fopen(video_dst_filename, "wb"); |
| if (!video_dst_file) { |
| fprintf(stderr, "Could not open destination file %s\n", video_dst_filename); |
| ret = 1; |
| goto end; |
| } |
| |
| /* allocate image where the decoded image will be put */ |
| width = video_dec_ctx->width; |
| height = video_dec_ctx->height; |
| pix_fmt = video_dec_ctx->pix_fmt; |
| ret = av_image_alloc(video_dst_data, video_dst_linesize, |
| width, height, pix_fmt, 1); |
| if (ret < 0) { |
| fprintf(stderr, "Could not allocate raw video buffer\n"); |
| goto end; |
| } |
| video_dst_bufsize = ret; |
| } |
| |
| if (open_codec_context(&audio_stream_idx, &audio_dec_ctx, fmt_ctx, AVMEDIA_TYPE_AUDIO) >= 0) { |
| audio_stream = fmt_ctx->streams[audio_stream_idx]; |
| audio_dst_file = fopen(audio_dst_filename, "wb"); |
| if (!audio_dst_file) { |
| fprintf(stderr, "Could not open destination file %s\n", audio_dst_filename); |
| ret = 1; |
| goto end; |
| } |
| } |
| |
| /* dump input information to stderr */ |
| av_dump_format(fmt_ctx, 0, src_filename, 0); |
| |
| if (!audio_stream && !video_stream) { |
| fprintf(stderr, "Could not find audio or video stream in the input, aborting\n"); |
| ret = 1; |
| goto end; |
| } |
| |
| frame = av_frame_alloc(); |
| if (!frame) { |
| fprintf(stderr, "Could not allocate frame\n"); |
| ret = AVERROR(ENOMEM); |
| goto end; |
| } |
| |
| /* initialize packet, set data to NULL, let the demuxer fill it */ |
| av_init_packet(&pkt); |
| pkt.data = NULL; |
| pkt.size = 0; |
| |
| if (video_stream) |
| printf("Demuxing video from file '%s' into '%s'\n", src_filename, video_dst_filename); |
| if (audio_stream) |
| printf("Demuxing audio from file '%s' into '%s'\n", src_filename, audio_dst_filename); |
| |
| /* read frames from the file */ |
| while (av_read_frame(fmt_ctx, &pkt) >= 0) { |
| AVPacket orig_pkt = pkt; |
| do { |
| ret = decode_packet(&got_frame, 0); |
| if (ret < 0) |
| break; |
| pkt.data += ret; |
| pkt.size -= ret; |
| } while (pkt.size > 0); |
| av_packet_unref(&orig_pkt); |
| } |
| |
| /* flush cached frames */ |
| pkt.data = NULL; |
| pkt.size = 0; |
| do { |
| decode_packet(&got_frame, 1); |
| } while (got_frame); |
| |
| printf("Demuxing succeeded.\n"); |
| |
| if (video_stream) { |
| printf("Play the output video file with the command:\n" |
| "ffplay -f rawvideo -pix_fmt %s -video_size %dx%d %s\n", |
| av_get_pix_fmt_name(pix_fmt), width, height, |
| video_dst_filename); |
| } |
| |
| if (audio_stream) { |
| enum AVSampleFormat sfmt = audio_dec_ctx->sample_fmt; |
| int n_channels = audio_dec_ctx->channels; |
| const char *fmt; |
| |
| if (av_sample_fmt_is_planar(sfmt)) { |
| const char *packed = av_get_sample_fmt_name(sfmt); |
| printf("Warning: the sample format the decoder produced is planar " |
| "(%s). This example will output the first channel only.\n", |
| packed ? packed : "?"); |
| sfmt = av_get_packed_sample_fmt(sfmt); |
| n_channels = 1; |
| } |
| |
| if ((ret = get_format_from_sample_fmt(&fmt, sfmt)) < 0) |
| goto end; |
| |
| printf("Play the output audio file with the command:\n" |
| "ffplay -f %s -ac %d -ar %d %s\n", |
| fmt, n_channels, audio_dec_ctx->sample_rate, |
| audio_dst_filename); |
| } |
| |
| end: |
| avcodec_free_context(&video_dec_ctx); |
| avcodec_free_context(&audio_dec_ctx); |
| avformat_close_input(&fmt_ctx); |
| if (video_dst_file) |
| fclose(video_dst_file); |
| if (audio_dst_file) |
| fclose(audio_dst_file); |
| av_frame_free(&frame); |
| av_free(video_dst_data[0]); |
| |
| return ret < 0; |
| } |