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• FFMPEG Can't Display The Duration Of a Video

  27 juillet 2015, par Malkavian

  I’m trying to use ffmpeg to capture frames from a video file, but I can’t even get the duration of a video. everytime when I try to access it with pFormatCtx->duration I’m getting 0. I know the pointer initialized and contains the correct duration because if I use av_dump_format(pFormatCtx, 0, videoName, 0); then I actually get the duration data along with other information about the video.
  This is what I get when I use av_dump_format(pFormatCtx, 0, videoName, 0); :

  Input #0, avi, from ’futurama.avi’ :

  Duration : 00:21:36.28, start : 0.000000, bitrate : 1135 kb/s

  Stream #0.0 : Video : mpeg4 (Advanced Simple Profile), yuv420p, 512x384

  [PAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc

  Stream #0.1 : Audio : ac3, 48000 Hz, stereo, s16, 192 kb/s

  I don’t understand why av_dum_format can display duration and I can’t. I checked the function definition, to display the duration, the function also uses pFormatCtx->duration. It’s not just the duration other member variables also don’t display the proper data when I call them in main.cpp

  Here’s my main.cpp :

  extern "C" {
  
      #include<libavcodec></libavcodec>avcodec.h>
  
      #include<libavformat></libavformat>avformat.h>
  
      #include<libswscale></libswscale>swscale.h>
  
  }
  
  
  
  
  
  int main(int argc, char *argv[]) {
  
      AVFormatContext *pFormatCtx = NULL;
  
  
  
      const char videoName[] = "futurama.avi";
  
  
  
      // Register all formats and codecs.
  
      av_register_all();
  
      cout &lt;&lt; "Opening the video file";
  
      // Open video file
  
      int ret = avformat_open_input(&amp;pFormatCtx, videoName, NULL, NULL) != 0;
  
      if (ret != 0) {
  
          cout &lt;&lt; "Couldn't open the video file." &lt;&lt; ret ;
  
          return -1;
  
      }
  
      if(avformat_find_stream_info(pFormatCtx, 0) &lt; 0) {
  
          cout &lt;&lt; "problem with stream info";
  
          return -1;
  
      }
  
  
  
      av_dump_format(pFormatCtx, 0, videoName, 0);
  
      cout &lt;&lt; pFormatCtx->bit_rate &lt;&lt; endl; // different value each time, not initialized properly.
  
      cout &lt;&lt; pFormatCtx->duration &lt;&lt; endl; // 0
  
      return 0;
  
  }

  I don’t know if it helps but, I use QtCreator on Ubuntu and linked the libraries statically.

  Thank you for your help.

• fate : Add test for APV 422-10 profile

  27 avril, par Mark Thompson

  fate : Add test for APV 422-10 profile
  Bitstream generated using the reference encoder, then edited to fix the
  
  colour description and an extra metadata block added.  FFmpeg decoder
  
  output is identical to the reference decoder output.
  The content used is the first three frames of "Waterfall" from the SVT
  
  Open Content Video Test Suite 2022.  This is copyright Sveriges
  
  Television AB and is used under the Creative Commons Attribution 4.0
  
  International License.
  

  • [DH] tests/Makefile
  • [DH] tests/fate/apv.mak
  • [DH] tests/ref/fate/apv-422-10

• ffmpeg mp4 to hls transcode fails on Azure Windows Server Image [closed]

  13 février, par James Weatherhead

  I am having an issue with transcoding an mp4 (any mp4) to hls. If I run the command below on my Windows 11 machine it works fine. If I run it on a clean Windows 11 VM, it works fine. If I run it on a clean Windows 2022 Server VM it works fine. If I create a Windows 2022 server image in Azure and run it... it fails (see error below)

  


  I feel like something that FFMPEG needs is missing from the default server image in Azure. Has anyone experienced this issue and found a way to solve it ?

  


  The command I am using :

  


  ffmpeg.exe -i LowPriVMs-1.mp4 -filter_complex "[0:v]split=1[v1] ; [v1]scale=w=1920:h=1080[v1out] ; " -map "[v1out]" -c:v:0 mpeg4 -b:v:0 5000k -maxrate:v:0 5350k -bufsize:v:0 7500k -map a:0 -c:a aac -b:a:0 192k -ac 2 -f hls -hls_time 10 -hls_playlist_type vod -hls_flags independent_segments -hls_segment_type mpegts -hls_segment_filename stream_%v/data%03d.ts -master_pl_name master.m3u8 -var_stream_map "v:0,a:0" stream_%v/playlist.m3u8

  


  The error returned by FFMPEG is :

  


  [out#0/hls @ 00000204c6aded40] Could not write header (incorrect codec parameters ?) : Invalid argument

  


  Has anyone else encountered this and found a solution ? I wondered if it is required to add a Feature Pack or some such dependency to Windows ?

  


  Thanks
James