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• Why does every encoded frame's size increase after I had use to set one frame to be key in intel qsv of ffmpeg

  22 avril 2021, par TONY

  I used intel's qsv to encode h264 video in ffmpeg. My av codec context settings is like as below :

  


   m_ctx->width = m_width;
    m_ctx->height = m_height;
    m_ctx->time_base = { 1, (int)fps };
    m_ctx->qmin = 10;
    m_ctx->qmax = 35;
    m_ctx->gop_size = 3000;
    m_ctx->max_b_frames = 0;
    m_ctx->has_b_frames = false;
    m_ctx->refs = 2;
    m_ctx->slices = 0;
    m_ctx->codec_id = m_encoder->id;
    m_ctx->codec_type = AVMEDIA_TYPE_VIDEO;
    m_ctx->pix_fmt = m_h264InputFormat;
    m_ctx->compression_level = 4;
    m_ctx->flags &= ~AV_CODEC_FLAG_CLOSED_GOP;
    AVDictionary *param = nullptr;
    av_dict_set(&param, "idr_interval", "0", 0);
    av_dict_set(&param, "async_depth", "1", 0);
    av_dict_set(&param, "forced_idr", "1", 0);


  


  and in the encoding, I set the AVFrame to be AV_PICTURE_TYPE_I when key frame is needed :

  


    if(key_frame){
        encodeFrame->pict_type = AV_PICTURE_TYPE_I;
    }else{
        encodeFrame->pict_type = AV_PICTURE_TYPE_NONE;
    }
    avcodec_send_frame(m_ctx, encodeFrame);
    avcodec_receive_packet(m_ctx, m_packet);
   std::cerr<<"packet size is "<size<<",is key frame "<code>

  


  The strange phenomenon is that if I had set one frame to AV_PICTURE_TYPE_I, then every encoded frame's size after the key frame would increase. If I change the h264 encoder to x264, then it's ok.

  


  The packet size is as below before I call "encodeFrame->pict_type = AV_PICTURE_TYPE_I" :

  


  packet size is 26839
packet size is 2766
packet size is 2794
packet size is 2193
packet size is 1820
packet size is 2542
packet size is 2024
packet size is 1692
packet size is 2095
packet size is 2550
packet size is 1685
packet size is 1800
packet size is 2276
packet size is 1813
packet size is 2206
packet size is 2745
packet size is 2334
packet size is 2623
packet size is 2055


  


  If I call "encodeFrame->pict_type = AV_PICTURE_TYPE_I", then the packet size is as below :

  


  packet size is 23720,is key frame 1
packet size is 23771,is key frame 0
packet size is 23738,is key frame 0
packet size is 23752,is key frame 0
packet size is 23771,is key frame 0
packet size is 23763,is key frame 0
packet size is 23715,is key frame 0
packet size is 23686,is key frame 0
packet size is 23829,is key frame 0
packet size is 23774,is key frame 0
packet size is 23850,is key frame 0


  


• FFMPEG in Node.js : Conversion Failed

  11 juillet 2024, par cuneyttyler

  I have a small node.js web app. I use like this in a get request :

  


  app.get('/api/voice/:gender/:voice/:pitch', function(req, res){
        if(req.params.pitch == "1" || req.params.pitch == "1.0") {
            const file = "./voices/" + req.params.gender.toLowerCase() + "/" + req.params.voice + ".mp3"
            res.download(file);
            return
        }

        const inputFile = "./voices/" + req.params.gender.toLowerCase() + "/" + req.params.voice + ".mp3"
        const output_file = "./Audio/Temp/" + req.params.voice + ".mp3"
        ffmpeg()
                .input(inputFile)
                .audioCodec('pcm_s16le') // Set the audio codec to PCM with 16-bit depth
                .audioFrequency(44100) // Set the sample rate
                .on('error', function(err) {
                    console.error('Error while converting:', err);
                })
                .on('end', function() {
                    // res.download(output_file)
                })
                .save(output_file);

    });


  


  It gives Conversion Failed error :

  


  [2024-07-11T18:11:22.880Z] Error while converting: Error: ffmpeg exited with code 1: Conversion failed!&#xA;&#xA;    at ChildProcess.<anonymous> (d:\Dev\Anima\Client\node_modules\fluent-ffmpeg\lib\processor.js:180:22)&#xA;    at ChildProcess.emit (d:\Dev\Anima\Client\lib\events.js:519:28)&#xA;    at ChildProcess._handle.onexit (d:\Dev\Anima\Client\lib\internal\child_process.js:294:12)&#xA;    at Process.callbackTrampoline (node:internal/async_hooks:130:17) {stack: &#x27;Error: ffmpeg exited with code 1: Conversion …Trampoline (node:internal/async_hooks:130:17)&#x27;, message: &#x27;ffmpeg exited with code 1: Conversion failed!&#xA;&#x27;}&#xA;</anonymous>

  


  When I use same code in a node.js desktop(.exe) app, it successfully runs. When I use it in an express.js app, it fails. Error message is not clear. What is the issue ?

  


• lavc/vvc : Check slice structure

  10 janvier, par Frank Plowman

  lavc/vvc : Check slice structure
  The criteria for slice structure validity is similar to that of
  
  subpicture structure validity that we saw not too long ago [1].
  
  The relationship between tiles and slices must satisfy the following
  
  properties :
  * Exhaustivity.  All tiles in a picture must belong to a slice.  The
  
    tiles cover the picture, so this implies the slices must cover the
  
    picture.
  
  * Mutual exclusivity.  No tile may belong to more than one slice, i.e.
  
    slices may not overlap.
  In most cases these properties are guaranteed by the syntax.  There is
  
  one noticable exception however : when pps_tile_idx_delta_present_flag is
  
  equal to one, each slice is associated with a syntax element
  
  pps_tile_idx_delta_val[i] which "specifies the difference between the
  
  tile index of the tile containing the first CTU in the ( i + 1 )-th
  
  rectangular slice and the tile index of the tile containing the first
  
  CTU in the i-th rectangular slice" [2].  When these syntax elements are
  
  present, the i-th slice can begin anywhere and the usual guarantees
  
  provided by the syntax are lost.
  The patch detects slice structures which violate either of the two
  
  properties above, and are therefore invalid, while building the
  
  slice map.  Should the slice map be determined to be invalid, an
  
  AVERROR_INVALIDDATA is returned.  This prevents issues including
  
  segmentation faults when trying to decode,  invalid bitstreams.
  [1] : https://ffmpeg.org//pipermail/ffmpeg-devel/2024-October/334470.html
  
  [2] : H.266 (V3) Section 7.4.3.5, Picture parameter set RBSP semantics
  Signed-off-by : Frank Plowman <post@frankplowman.com>
  

  • [DH] libavcodec/vvc/ps.c