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    Jolie sélection multiple
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  • Le profil des utilisateurs

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    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
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  • Configurer la prise en compte des langues

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    Accéder à la configuration et ajouter des langues prises en compte
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Sur d’autres sites (8949)

  • How to get xml/json output when ffprobe could not find codec parameters for a stream

    9 juin 2015, par user2421731

    I was using ffprobe on a mkv file in order to get some info about the chapter structure so as to split the mkv using ffmpeg.

    ffprobe miku.mkv -print_format xml

    However ffprobe encountered an scodec error(does not affect chapter info) and I could not get the info by setting print format. I know there are ways like pipeline to bypass the error, but I still want to get the xml/json file so it can be parsed easily.

    I wonder if there is a way to ingore the error and output the xml/json file or is there a solution to the error. (But I prefer a solution to the former, because I don’t know what any errors I might encounter and I’d like to see it works as long as the chapter info is available)

    The error was like this.

    ffprobe version N-60899-ga8ad7e4 Copyright (c) 2007-2014 the FFmpeg developers
  built on Feb 25 2014 04:04:01 with gcc 4.8.2 (GCC)
  configuration : —enable-gpl —enable-version3 —disable-w32threads —enable-avisynth —enable-bzlib —enable-fontconfig —enable-frei0r —enable-gnutls —enable-iconv —enable-libass —enable-libbluray —enable-libcaca —enable-libfreetype —enable-libgsm —enable-libilbc —enable-libmodplug —enable-libmp3lame —enable-libopencore-amrnb —enable-libopencore-amrwb —enable-libopenjpeg —enable-libopus —enable-librtmp —enable-libschroedinger —enable-libsoxr —enable-libspeex —enable-libtheora —enable-libtwolame —enable-libvidstab —enable-libvo-aacenc —enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx —enable-libwavpack —enable-libx264 —enable-libx265 —enable-libxavs —enable-libxvid —enable-zlib
  libavutil      52. 66.100 / 52. 66.100
  libavcodec     55. 52.102 / 55. 52.102
  libavformat    55. 33.100 / 55. 33.100
  libavdevice    55. 10.100 / 55. 10.100
  libavfilter     4.  1.103 /  4.  1.103
  libswscale      2.  5.101 /  2.  5.101
  libswresample   0. 18.100 /  0. 18.100
  libpostproc    52.  3.100 / 52.  3.100
[matroska,webm @ 0000000002945080] Could not find codec parameters for stream 3 (Subtitle : hdmv_pgs_subtitle) : unspecified size
Consider increasing the value for the ’analyzeduration’ and ’probesize’ options
Input #0, matroska,webm, from ’[Hatsune Miku Magical Mirai 2013][JPN][BDRIP][1080P][H264_FLAC_DTS-HDMA].mkv’ :
  Metadata :
    encoder : libebml v1.3.0 + libmatroska v1.4.1
    creation_time : 2014-02-18 22:57:12
  Duration : 01:58:00.08, start : 0.000000, bitrate : 16495 kb/s
    Chapter #0.0 : start 0.000000, end 30.030000
    Metadata :
      title : Start
    Chapter #0.1 : start 30.030000, end 149.749000
    Metadata :
      title : 00. Opening Music
......

  • Transcoded video stream unplayable in QuickTime player

    30 novembre 2017, par Nikolai Linetskiy

    Currently I’m writing software for transcoding media files using ffmpeg libs. The problem is that in case of H264 QuickTime cannot play result stream and shows black screen. Audio streams work as expected. I have read that QuickTime can deal only with yuv420p pixel format and that is true for encoded video.

    I looked through the ffmpeg examples and ffmpeg source code and could not find anything find any clues where the problem might be. I would really appreciate any help.

    The only thing I managed to get from QuickTime is
    SeqAndPicParamSetFromCFDictionaryRef, bad config record message in console. Same thing is logged by AVPlayer from AVFoundation.

    Here is the initialization of output streams and encoders.

    int status;
    

    
// avformat_alloc_output_context2()
    
if ((status = formatContext.open(destFilename)) < 0) {
    
    return status;
    
}
    

    
AVDictionary *fmtOptions = nullptr;
    
av_dict_set(&fmtOptions, "movflags", "faststart", 0);
    
av_dict_set(&fmtOptions, "brand", "mp42", 0);
    

    
streams.resize(input->getStreamsCount());
    
for (int i = 0; i < input->getStreamsCount(); ++i) {
    
    AVStream *inputStream = input->getStreamAtIndex(i);
    
    CodecContext &decoderContext = input->getDecoderAtIndex(i);
    

    
    // retrieve output codec by codec id
    
    auto encoderCodecId = decoderContext.getCodecID();;
    
    if (decoderContext.getCodecType() == AVMEDIA_TYPE_VIDEO || decoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO) {
    
        int codecIdKey = decoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO ? IPROC_KEY_INT(TargetAudioCodecID) : IPROC_KEY_INT(TargetVideoCodecID);
    
        auto codecIdParam = static_cast<avcodecid>(params[codecIdKey]);
    
        if (codecIdParam != AV_CODEC_ID_NONE) {
    
            encoderCodecId = codecIdParam;
    
        }
    
    }
    
    AVCodec *encoder = nullptr;
    
    if ((encoder = avcodec_find_encoder(encoderCodecId)) == nullptr) {
    
        status = AVERROR_ENCODER_NOT_FOUND;
    
        return status;
    
    }
    

    
    // create stream with specific codec and format
    
    AVStream *outputStream = nullptr;
    
    // avformat_new_stream()
    
    if ((outputStream = formatContext.newStream(encoder)) == nullptr) {
    
        return AVERROR(ENOMEM);
    
    }
    

    

    
    CodecContext encoderContext;
    
    // avcodec_alloc_context3()
    
    if ((status = encoderContext.init(encoder)) &lt; 0) {
    
        return status;
    
    }
    

    
    outputStream->disposition = inputStream->disposition;
    
    encoderContext.getRawCtx()->chroma_sample_location = decoderContext.getRawCtx()->chroma_sample_location;
    

    
    if (encoderContext.getCodecType() == AVMEDIA_TYPE_VIDEO) {
    
        auto lang = av_dict_get(input->getStreamAtIndex(i)->metadata, "language", nullptr, 0);
    
        if (lang) {
    
            av_dict_set(&amp;outputStream->metadata, "language", lang->value, 0);
    
        }
    

    
        // prepare encoder context
    
        int targetWidth = params[IPROC_KEY_INT(TargetVideoWidth)];
    
        int targetHeight = params[IPROC_KEY_INT(TargetVideHeight)];
    

    

    

    
        encoderContext.width() = targetWidth > 0 ? targetWidth : decoderContext.width();
    
        encoderContext.height() = targetHeight > 0 ? targetHeight : decoderContext.height();
    
        encoderContext.pixelFormat() = encoder->pix_fmts ? encoder->pix_fmts[0] : decoderContext.pixelFormat();;
    
        encoderContext.timeBase() = decoderContext.timeBase();
    
        encoderContext.getRawCtx()->level = 31;
    
        encoderContext.getRawCtx()->gop_size = 25;
    

    
        double far = static_cast<double>(encoderContext.getRawCtx()->width) / encoderContext.getRawCtx()->height;
    
        double dar = static_cast<double>(decoderContext.width()) / decoderContext.height();
    
        encoderContext.sampleAspectRatio() = av_d2q(dar / far, 255);
    

    

    
        encoderContext.getRawCtx()->bits_per_raw_sample = FFMIN(decoderContext.getRawCtx()->bits_per_raw_sample,
    
                                                                av_pix_fmt_desc_get(encoderContext.pixelFormat())->comp[0].depth);
    
        encoderContext.getRawCtx()->framerate = inputStream->r_frame_rate;
    
        outputStream->avg_frame_rate = encoderContext.getRawCtx()->framerate;
    

    
        VideoFilterGraphParameters params;
    
        params.height = encoderContext.height();
    
        params.width = encoderContext.width();
    
        params.pixelFormat = encoderContext.pixelFormat();
    
        if ((status = generateGraph(decoderContext, encoderContext, params, streams[i].filterGraph)) &lt; 0) {
    
            return status;
    
        }
    

    
    } else if (encoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO) {
    
        auto lang = av_dict_get(input->getStreamAtIndex(i)->metadata, "language", nullptr, 0);
    
        if (lang) {
    
            av_dict_set(&amp;outputStream->metadata, "language", lang->value, 0);
    
        }
    

    
        encoderContext.sampleRate() = params[IPROC_KEY_INT(TargetAudioSampleRate)] ? : decoderContext.sampleRate();
    
        encoderContext.channels() = params[IPROC_KEY_INT(TargetAudioChannels)] ? : decoderContext.channels();
    
        auto paramChannelLayout = params[IPROC_KEY_INT(TargetAudioChannelLayout)];
    
        if (paramChannelLayout) {
    
            encoderContext.channelLayout() = paramChannelLayout;
    
        } else {
    
            encoderContext.channelLayout() = av_get_default_channel_layout(encoderContext.channels());
    
        }
    

    
        AVSampleFormat sampleFormatParam = static_cast<avsampleformat>(params[IPROC_KEY_INT(TargetAudioSampleFormat)]);
    
        if (sampleFormatParam != AV_SAMPLE_FMT_NONE) {
    
            encoderContext.sampleFormat() = sampleFormatParam;
    
        } else if (encoder->sample_fmts) {
    
            encoderContext.sampleFormat() = encoder->sample_fmts[0];
    
        } else {
    
            encoderContext.sampleFormat() = decoderContext.sampleFormat();
    
        }
    

    
        encoderContext.timeBase().num = 1;
    
        encoderContext.timeBase().den = encoderContext.sampleRate();
    

    
        AudioFilterGraphParameters params;
    
        params.channelLayout = encoderContext.channelLayout();
    
        params.channels = encoderContext.channels();
    
        params.format = encoderContext.sampleFormat();
    
        params.sampleRate = encoderContext.sampleRate();
    
        if ((status = generateGraph(decoderContext, encoderContext, params, streams[i].filterGraph)) &lt; 0) {
    
            return status;
    
        }
    
    }
    

    
    // before using encoder, we should open it and update its parameters
    
    printf("Codec bits per sample %d\n", av_get_bits_per_sample(encoderCodecId));
    
    AVDictionary *options = nullptr;
    
    // avcodec_open2()
    
    if ((status = encoderContext.open(encoder, &amp;options)) &lt; 0) {
    
        return status;
    
    }
    
    if (streams[i].filterGraph) {
    
        streams[i].filterGraph.setOutputFrameSize(encoderContext.getFrameSize());
    
    }
    
    // avcodec_parameters_from_context()
    
    if ((status = encoderContext.fillParamters(outputStream->codecpar)) &lt; 0) {
    
        return status;
    
    }
    
    outputStream->codecpar->format = encoderContext.getRawCtx()->pix_fmt;
    

    
    if (formatContext.getRawCtx()->oformat->flags &amp; AVFMT_GLOBALHEADER) {
    
        encoderContext.getRawCtx()->flags |= CODEC_FLAG_GLOBAL_HEADER;
    
    }
    

    
    if (encoderContext.getRawCtx()->nb_coded_side_data) {
    
        int i;
    

    
        for (i = 0; i &lt; encoderContext.getRawCtx()->nb_coded_side_data; i++) {
    
            const AVPacketSideData *sd_src = &amp;encoderContext.getRawCtx()->coded_side_data[i];
    
            uint8_t *dst_data;
    

    
            dst_data = av_stream_new_side_data(outputStream, sd_src->type, sd_src->size);
    
            if (!dst_data)
    
                return AVERROR(ENOMEM);
    
            memcpy(dst_data, sd_src->data, sd_src->size);
    
        }
    
    }
    

    
    /*
    
     * Add global input side data. For now this is naive, and copies it
    
     * from the input stream's global side data. All side data should
    
     * really be funneled over AVFrame and libavfilter, then added back to
    
     * packet side data, and then potentially using the first packet for
    
     * global side data.
    
     */
    
    for (int i = 0; i &lt; inputStream->nb_side_data; i++) {
    
        AVPacketSideData *sd = &amp;inputStream->side_data[i];
    
        uint8_t *dst = av_stream_new_side_data(outputStream, sd->type, sd->size);
    
        if (!dst)
    
            return AVERROR(ENOMEM);
    
        memcpy(dst, sd->data, sd->size);
    
    }
    

    
    // copy timebase while removing common factors
    
    if (outputStream->time_base.num &lt;= 0 || outputStream->time_base.den &lt;= 0) {
    
        outputStream->time_base = av_add_q(encoderContext.timeBase(), (AVRational){0, 1});
    
    }
    

    
    // copy estimated duration as a hint to the muxer
    
    if (outputStream->duration &lt;= 0 &amp;&amp; inputStream->duration > 0) {
    
        outputStream->duration = av_rescale_q(inputStream->duration, inputStream->time_base, outputStream->time_base);
    
    }
    

    
    streams[i].codecType = encoderContext.getRawCtx()->codec_type;
    
    streams[i].codec = std::move(encoderContext);
    
    streams[i].streamIndex = i;
    
}
    

    
// avio_open() and avformat_write_header()
    
if ((status = formatContext.writeHeader(fmtOptions)) &lt; 0) {
    
    return status;
    
}
    

    
formatContext.dumpFormat();
    
</avsampleformat></double></double></avcodecid>

    Reading from stream.

    int InputProcessor::performStep() {
    
    int status;
    

    
    Packet nextPacket;
    
    if ((status = input->getFormatContext().readFrame(nextPacket)) &lt; 0) {
    
        return status;
    
    }
    
    ++streams[nextPacket.getStreamIndex()].readPackets;
    
    int streamIndex = nextPacket.getStreamIndex();
    
    CodecContext &amp;decoder = input->getDecoderAtIndex(streamIndex);
    
    AVStream *inputStream = input->getStreamAtIndex(streamIndex);
    

    
    if (streams[nextPacket.getStreamIndex()].readPackets == 1) {
    
        for (int i = 0; i &lt; inputStream->nb_side_data; ++i) {
    
            AVPacketSideData *src_sd = &amp;inputStream->side_data[i];
    
            uint8_t *dst_data;
    

    
            if (src_sd->type == AV_PKT_DATA_DISPLAYMATRIX) {
    
                continue;
    
            }
    
            if (av_packet_get_side_data(nextPacket.getRawPtr(), src_sd->type, nullptr)) {
    
                continue;
    
            }
    
            dst_data = av_packet_new_side_data(nextPacket.getRawPtr(), src_sd->type, src_sd->size);
    
            if (!dst_data) {
    
                return AVERROR(ENOMEM);
    
            }
    
            memcpy(dst_data, src_sd->data, src_sd->size);
    
        }
    
    }
    

    
    nextPacket.rescaleTimestamps(inputStream->time_base, decoder.timeBase());
    

    
    status = decodePacket(&amp;nextPacket, nextPacket.getStreamIndex());
    
    if (status &lt; 0 &amp;&amp; status != AVERROR(EAGAIN)) {
    
        return status;
    
    }
    
    return 0;
    
}

    Here is decoding/encoding code.

    int InputProcessor::decodePacket(Packet *packet, int streamIndex) {
    
    int status;
    
    int sendStatus;
    

    
    auto &amp;decoder = input->getDecoderAtIndex(streamIndex);
    

    
    do {
    
        if (packet == nullptr) {
    

    
            sendStatus = decoder.flushDecodedFrames();
    
        } else {
    
            sendStatus = decoder.sendPacket(*packet);
    
        }
    

    
        if (sendStatus &lt; 0 &amp;&amp; sendStatus != AVERROR(EAGAIN) &amp;&amp; sendStatus != AVERROR_EOF) {
    
            return sendStatus;
    
        }
    
        if (sendStatus == 0 &amp;&amp; packet) {
    
            ++streams[streamIndex].decodedPackets;
    
        }
    

    
        Frame decodedFrame;
    
        while (true) {
    
            if ((status = decoder.receiveFrame(decodedFrame)) &lt; 0) {
    
                break;
    
            }
    
            ++streams[streamIndex].decodedFrames;
    
            if ((status = filterAndWriteFrame(&amp;decodedFrame, streamIndex)) &lt; 0) {
    
                break;
    
            }
    
            decodedFrame.unref();
    
        }
    
    } while (sendStatus == AVERROR(EAGAIN));
    

    
 return status;
    
}
    

    
int InputProcessor::encodeAndWriteFrame(Frame *frame, int streamIndex) {
    
    assert(input->isValid());
    
    assert(formatContext);
    

    
    int status = 0;
    
    int sendStatus;
    

    
    Packet packet;
    

    
    CodecContext &amp;encoderContext = streams[streamIndex].codec;
    

    
    do {
    
        if (frame) {
    
            sendStatus = encoderContext.sendFrame(*frame);
    
        } else {
    
            sendStatus = encoderContext.flushEncodedPackets();
    
        }
    
        if (sendStatus &lt; 0 &amp;&amp; sendStatus != AVERROR(EAGAIN) &amp;&amp; sendStatus != AVERROR_EOF) {
    
            return status;
    
        }
    
        if (sendStatus == 0 &amp;&amp; frame) {
    
            ++streams[streamIndex].encodedFrames;
    
        }
    

    
        while (true) {
    
            if ((status = encoderContext.receivePacket(packet)) &lt; 0) {
    
                break;
    
            }
    
            ++streams[streamIndex].encodedPackets;
    
            packet.setStreamIndex(streamIndex);
    
            auto sourceTimebase = encoderContext.timeBase();
    
            auto dstTimebase = formatContext.getStreams()[streamIndex]->time_base;
    
            packet.rescaleTimestamps(sourceTimebase, dstTimebase);
    
            if ((status = formatContext.writeFrameInterleaved(packet)) &lt; 0) {
    
                return status;
    
            }
    
            packet.unref();
    
        }
    
    } while (sendStatus == AVERROR(EAGAIN));
    

    
    if (status != AVERROR(EAGAIN)) {
    
        return status;
    
    }
    

    
    return 0;
    
}

    FFprobe output for original video.

    Input #0, matroska,webm, from 'testvideo':
    
  Metadata:
    
    title           : TestVideo
    
    encoder         : libebml v1.3.0 + libmatroska v1.4.0
    
    creation_time   : 2014-12-23T03:38:05.000000Z
    
  Duration: 00:02:29.25, start: 0.000000, bitrate: 79549 kb/s
    
    Stream #0:0(rus): Video: h264 (High 4:4:4 Predictive), yuv444p10le(pc, bt709, progressive), 2048x858 [SAR 1:1 DAR 1024:429], 24 fps, 24 tbr, 1k tbn, 48 tbc (default)
    
    Stream #0:1(rus): Audio: pcm_s24le, 48000 Hz, 6 channels, s32 (24 bit), 6912 kb/s (default)

    Transcoded :

    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '123.mp4':
    
  Metadata:
    
    major_brand     : mp42
    
    minor_version   : 512
    
    compatible_brands: isomiso2avc1mp41
    
    encoder         : Lavf57.71.100
    
  Duration: 00:02:29.27, start: 0.000000, bitrate: 4282 kb/s
    
    Stream #0:0(rus): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 192:143 DAR 1024:429], 3940 kb/s, 24.01 fps, 24 tbr, 12288 tbn, 96 tbc (default)
    
    Metadata:
    
      handler_name    : VideoHandler
    
    Stream #0:1(rus): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 5.1, fltp, 336 kb/s (default)
    
    Metadata:
    
      handler_name    : SoundHandler

  • Resultant video stream unplayable

    29 novembre 2017, par Nikolai Linetskiy

    Currently I’m writing software for transcoding media files using ffmpeg libs. The problem is that in case of H264 QuickTime cannot play result stream and shows black screen. Audio streams work as expected. I have read that QuickTime can deal only with yuv420p pixel format and that is true for encoded video.

    I looked through the ffmpeg examples and ffmpeg source code and could not find anything find any clues where the problem might be. I would really appreciate any help.

    The only thing I managed to get from QuickTime is
    SeqAndPicParamSetFromCFDictionaryRef, bad config record message in console. Same thing is logged by AVPlayer from AVFoundation.

    Here is the initialization of output streams and encoders.

    int status;
    

    
// avformat_alloc_output_context2()
    
if ((status = formatContext.open(destFilename)) &lt; 0) {
    
    return status;
    
}
    

    
AVDictionary *fmtOptions = nullptr;
    
av_dict_set(&amp;fmtOptions, "movflags", "faststart", 0);
    
av_dict_set(&amp;fmtOptions, "brand", "mp42", 0);
    

    
streams.resize(input->getStreamsCount());
    
for (int i = 0; i &lt; input->getStreamsCount(); ++i) {
    
    AVStream *inputStream = input->getStreamAtIndex(i);
    
    CodecContext &amp;decoderContext = input->getDecoderAtIndex(i);
    

    
    // retrieve output codec by codec id
    
    auto encoderCodecId = decoderContext.getCodecID();;
    
    if (decoderContext.getCodecType() == AVMEDIA_TYPE_VIDEO || decoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO) {
    
        int codecIdKey = decoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO ? IPROC_KEY_INT(TargetAudioCodecID) : IPROC_KEY_INT(TargetVideoCodecID);
    
        auto codecIdParam = static_cast<avcodecid>(params[codecIdKey]);
    
        if (codecIdParam != AV_CODEC_ID_NONE) {
    
            encoderCodecId = codecIdParam;
    
        }
    
    }
    
    AVCodec *encoder = nullptr;
    
    if ((encoder = avcodec_find_encoder(encoderCodecId)) == nullptr) {
    
        status = AVERROR_ENCODER_NOT_FOUND;
    
        return status;
    
    }
    

    
    // create stream with specific codec and format
    
    AVStream *outputStream = nullptr;
    
    // avformat_new_stream()
    
    if ((outputStream = formatContext.newStream(encoder)) == nullptr) {
    
        return AVERROR(ENOMEM);
    
    }
    

    

    
    CodecContext encoderContext;
    
    // avcodec_alloc_context3()
    
    if ((status = encoderContext.init(encoder)) &lt; 0) {
    
        return status;
    
    }
    

    
    outputStream->disposition = inputStream->disposition;
    
    encoderContext.getRawCtx()->chroma_sample_location = decoderContext.getRawCtx()->chroma_sample_location;
    

    
    if (encoderContext.getCodecType() == AVMEDIA_TYPE_VIDEO) {
    
        auto lang = av_dict_get(input->getStreamAtIndex(i)->metadata, "language", nullptr, 0);
    
        if (lang) {
    
            av_dict_set(&amp;outputStream->metadata, "language", lang->value, 0);
    
        }
    

    
        // prepare encoder context
    
        int targetWidth = params[IPROC_KEY_INT(TargetVideoWidth)];
    
        int targetHeight = params[IPROC_KEY_INT(TargetVideHeight)];
    

    

    

    
        encoderContext.width() = targetWidth > 0 ? targetWidth : decoderContext.width();
    
        encoderContext.height() = targetHeight > 0 ? targetHeight : decoderContext.height();
    
        encoderContext.pixelFormat() = encoder->pix_fmts ? encoder->pix_fmts[0] : decoderContext.pixelFormat();;
    
        encoderContext.timeBase() = decoderContext.timeBase();
    
        encoderContext.getRawCtx()->level = 31;
    
        encoderContext.getRawCtx()->gop_size = 25;
    

    
        double far = static_cast<double>(encoderContext.getRawCtx()->width) / encoderContext.getRawCtx()->height;
    
        double dar = static_cast<double>(decoderContext.width()) / decoderContext.height();
    
        encoderContext.sampleAspectRatio() = av_d2q(dar / far, 255);
    

    

    
        encoderContext.getRawCtx()->bits_per_raw_sample = FFMIN(decoderContext.getRawCtx()->bits_per_raw_sample,
    
                                                                av_pix_fmt_desc_get(encoderContext.pixelFormat())->comp[0].depth);
    
        encoderContext.getRawCtx()->framerate = inputStream->r_frame_rate;
    
        outputStream->avg_frame_rate = encoderContext.getRawCtx()->framerate;
    

    
        VideoFilterGraphParameters params;
    
        params.height = encoderContext.height();
    
        params.width = encoderContext.width();
    
        params.pixelFormat = encoderContext.pixelFormat();
    
        if ((status = generateGraph(decoderContext, encoderContext, params, streams[i].filterGraph)) &lt; 0) {
    
            return status;
    
        }
    

    
    } else if (encoderContext.getCodecType() == AVMEDIA_TYPE_AUDIO) {
    
        auto lang = av_dict_get(input->getStreamAtIndex(i)->metadata, "language", nullptr, 0);
    
        if (lang) {
    
            av_dict_set(&amp;outputStream->metadata, "language", lang->value, 0);
    
        }
    

    
        encoderContext.sampleRate() = params[IPROC_KEY_INT(TargetAudioSampleRate)] ? : decoderContext.sampleRate();
    
        encoderContext.channels() = params[IPROC_KEY_INT(TargetAudioChannels)] ? : decoderContext.channels();
    
        auto paramChannelLayout = params[IPROC_KEY_INT(TargetAudioChannelLayout)];
    
        if (paramChannelLayout) {
    
            encoderContext.channelLayout() = paramChannelLayout;
    
        } else {
    
            encoderContext.channelLayout() = av_get_default_channel_layout(encoderContext.channels());
    
        }
    

    
        AVSampleFormat sampleFormatParam = static_cast<avsampleformat>(params[IPROC_KEY_INT(TargetAudioSampleFormat)]);
    
        if (sampleFormatParam != AV_SAMPLE_FMT_NONE) {
    
            encoderContext.sampleFormat() = sampleFormatParam;
    
        } else if (encoder->sample_fmts) {
    
            encoderContext.sampleFormat() = encoder->sample_fmts[0];
    
        } else {
    
            encoderContext.sampleFormat() = decoderContext.sampleFormat();
    
        }
    

    
        encoderContext.timeBase().num = 1;
    
        encoderContext.timeBase().den = encoderContext.sampleRate();
    

    
        AudioFilterGraphParameters params;
    
        params.channelLayout = encoderContext.channelLayout();
    
        params.channels = encoderContext.channels();
    
        params.format = encoderContext.sampleFormat();
    
        params.sampleRate = encoderContext.sampleRate();
    
        if ((status = generateGraph(decoderContext, encoderContext, params, streams[i].filterGraph)) &lt; 0) {
    
            return status;
    
        }
    
    }
    

    
    // before using encoder, we should open it and update its parameters
    
    printf("Codec bits per sample %d\n", av_get_bits_per_sample(encoderCodecId));
    
    AVDictionary *options = nullptr;
    
    // avcodec_open2()
    
    if ((status = encoderContext.open(encoder, &amp;options)) &lt; 0) {
    
        return status;
    
    }
    
    if (streams[i].filterGraph) {
    
        streams[i].filterGraph.setOutputFrameSize(encoderContext.getFrameSize());
    
    }
    
    // avcodec_parameters_from_context()
    
    if ((status = encoderContext.fillParamters(outputStream->codecpar)) &lt; 0) {
    
        return status;
    
    }
    
    outputStream->codecpar->format = encoderContext.getRawCtx()->pix_fmt;
    

    
    if (formatContext.getRawCtx()->oformat->flags &amp; AVFMT_GLOBALHEADER) {
    
        encoderContext.getRawCtx()->flags |= CODEC_FLAG_GLOBAL_HEADER;
    
    }
    

    
    if (encoderContext.getRawCtx()->nb_coded_side_data) {
    
        int i;
    

    
        for (i = 0; i &lt; encoderContext.getRawCtx()->nb_coded_side_data; i++) {
    
            const AVPacketSideData *sd_src = &amp;encoderContext.getRawCtx()->coded_side_data[i];
    
            uint8_t *dst_data;
    

    
            dst_data = av_stream_new_side_data(outputStream, sd_src->type, sd_src->size);
    
            if (!dst_data)
    
                return AVERROR(ENOMEM);
    
            memcpy(dst_data, sd_src->data, sd_src->size);
    
        }
    
    }
    

    
    /*
    
     * Add global input side data. For now this is naive, and copies it
    
     * from the input stream's global side data. All side data should
    
     * really be funneled over AVFrame and libavfilter, then added back to
    
     * packet side data, and then potentially using the first packet for
    
     * global side data.
    
     */
    
    for (int i = 0; i &lt; inputStream->nb_side_data; i++) {
    
        AVPacketSideData *sd = &amp;inputStream->side_data[i];
    
        uint8_t *dst = av_stream_new_side_data(outputStream, sd->type, sd->size);
    
        if (!dst)
    
            return AVERROR(ENOMEM);
    
        memcpy(dst, sd->data, sd->size);
    
    }
    

    
    // copy timebase while removing common factors
    
    if (outputStream->time_base.num &lt;= 0 || outputStream->time_base.den &lt;= 0) {
    
        outputStream->time_base = av_add_q(encoderContext.timeBase(), (AVRational){0, 1});
    
    }
    

    
    // copy estimated duration as a hint to the muxer
    
    if (outputStream->duration &lt;= 0 &amp;&amp; inputStream->duration > 0) {
    
        outputStream->duration = av_rescale_q(inputStream->duration, inputStream->time_base, outputStream->time_base);
    
    }
    

    
    streams[i].codecType = encoderContext.getRawCtx()->codec_type;
    
    streams[i].codec = std::move(encoderContext);
    
    streams[i].streamIndex = i;
    
}
    

    
// avio_open() and avformat_write_header()
    
if ((status = formatContext.writeHeader(fmtOptions)) &lt; 0) {
    
    return status;
    
}
    

    
formatContext.dumpFormat();
    
</avsampleformat></double></double></avcodecid>

    Reading from stream.

    int InputProcessor::performStep() {
    
    int status;
    

    
    Packet nextPacket;
    
    if ((status = input->getFormatContext().readFrame(nextPacket)) &lt; 0) {
    
        return status;
    
    }
    
    ++streams[nextPacket.getStreamIndex()].readPackets;
    
    int streamIndex = nextPacket.getStreamIndex();
    
    CodecContext &amp;decoder = input->getDecoderAtIndex(streamIndex);
    
    AVStream *inputStream = input->getStreamAtIndex(streamIndex);
    

    
    if (streams[nextPacket.getStreamIndex()].readPackets == 1) {
    
        for (int i = 0; i &lt; inputStream->nb_side_data; ++i) {
    
            AVPacketSideData *src_sd = &amp;inputStream->side_data[i];
    
            uint8_t *dst_data;
    

    
            if (src_sd->type == AV_PKT_DATA_DISPLAYMATRIX) {
    
                continue;
    
            }
    
            if (av_packet_get_side_data(nextPacket.getRawPtr(), src_sd->type, nullptr)) {
    
                continue;
    
            }
    
            dst_data = av_packet_new_side_data(nextPacket.getRawPtr(), src_sd->type, src_sd->size);
    
            if (!dst_data) {
    
                return AVERROR(ENOMEM);
    
            }
    
            memcpy(dst_data, src_sd->data, src_sd->size);
    
        }
    
    }
    

    
    nextPacket.rescaleTimestamps(inputStream->time_base, decoder.timeBase());
    

    
    status = decodePacket(&amp;nextPacket, nextPacket.getStreamIndex());
    
    if (status &lt; 0 &amp;&amp; status != AVERROR(EAGAIN)) {
    
        return status;
    
    }
    
    return 0;
    
}

    Here is decoding/encoding code.

    int InputProcessor::decodePacket(Packet *packet, int streamIndex) {
    
    int status;
    
    int sendStatus;
    

    
    auto &amp;decoder = input->getDecoderAtIndex(streamIndex);
    

    
    do {
    
        if (packet == nullptr) {
    

    
            sendStatus = decoder.flushDecodedFrames();
    
        } else {
    
            sendStatus = decoder.sendPacket(*packet);
    
        }
    

    
        if (sendStatus &lt; 0 &amp;&amp; sendStatus != AVERROR(EAGAIN) &amp;&amp; sendStatus != AVERROR_EOF) {
    
            return sendStatus;
    
        }
    
        if (sendStatus == 0 &amp;&amp; packet) {
    
            ++streams[streamIndex].decodedPackets;
    
        }
    

    
        Frame decodedFrame;
    
        while (true) {
    
            if ((status = decoder.receiveFrame(decodedFrame)) &lt; 0) {
    
                break;
    
            }
    
            ++streams[streamIndex].decodedFrames;
    
            if ((status = filterAndWriteFrame(&amp;decodedFrame, streamIndex)) &lt; 0) {
    
                break;
    
            }
    
            decodedFrame.unref();
    
        }
    
    } while (sendStatus == AVERROR(EAGAIN));
    

    
 return status;
    
}
    

    
int InputProcessor::encodeAndWriteFrame(Frame *frame, int streamIndex) {
    
    assert(input->isValid());
    
    assert(formatContext);
    

    
    int status = 0;
    
    int sendStatus;
    

    
    Packet packet;
    

    
    CodecContext &amp;encoderContext = streams[streamIndex].codec;
    

    
    do {
    
        if (frame) {
    
            sendStatus = encoderContext.sendFrame(*frame);
    
        } else {
    
            sendStatus = encoderContext.flushEncodedPackets();
    
        }
    
        if (sendStatus &lt; 0 &amp;&amp; sendStatus != AVERROR(EAGAIN) &amp;&amp; sendStatus != AVERROR_EOF) {
    
            return status;
    
        }
    
        if (sendStatus == 0 &amp;&amp; frame) {
    
            ++streams[streamIndex].encodedFrames;
    
        }
    

    
        while (true) {
    
            if ((status = encoderContext.receivePacket(packet)) &lt; 0) {
    
                break;
    
            }
    
            ++streams[streamIndex].encodedPackets;
    
            packet.setStreamIndex(streamIndex);
    
            auto sourceTimebase = encoderContext.timeBase();
    
            auto dstTimebase = formatContext.getStreams()[streamIndex]->time_base;
    
            packet.rescaleTimestamps(sourceTimebase, dstTimebase);
    
            if ((status = formatContext.writeFrameInterleaved(packet)) &lt; 0) {
    
                return status;
    
            }
    
            packet.unref();
    
        }
    
    } while (sendStatus == AVERROR(EAGAIN));
    

    
    if (status != AVERROR(EAGAIN)) {
    
        return status;
    
    }
    

    
    return 0;
    
}

    FFprobe output for original video.

    Input #0, matroska,webm, from 'testvideo':
    
  Metadata:
    
    title           : TestVideo
    
    encoder         : libebml v1.3.0 + libmatroska v1.4.0
    
    creation_time   : 2014-12-23T03:38:05.000000Z
    
  Duration: 00:02:29.25, start: 0.000000, bitrate: 79549 kb/s
    
    Stream #0:0(rus): Video: h264 (High 4:4:4 Predictive), yuv444p10le(pc, bt709, progressive), 2048x858 [SAR 1:1 DAR 1024:429], 24 fps, 24 tbr, 1k tbn, 48 tbc (default)
    
    Stream #0:1(rus): Audio: pcm_s24le, 48000 Hz, 6 channels, s32 (24 bit), 6912 kb/s (default)

    Transcoded :

    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '123.mp4':
    
  Metadata:
    
    major_brand     : mp42
    
    minor_version   : 512
    
    compatible_brands: isomiso2avc1mp41
    
    encoder         : Lavf57.71.100
    
  Duration: 00:02:29.27, start: 0.000000, bitrate: 4282 kb/s
    
    Stream #0:0(rus): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 192:143 DAR 1024:429], 3940 kb/s, 24.01 fps, 24 tbr, 12288 tbn, 96 tbc (default)
    
    Metadata:
    
      handler_name    : VideoHandler
    
    Stream #0:1(rus): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 5.1, fltp, 336 kb/s (default)
    
    Metadata:
    
      handler_name    : SoundHandler

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