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• FFMPEG 5 AVStream.cur_dts is removed

  14 octobre 2022, par John

  In the ffmpeg 5+, i noticed that the field cur_dts in AVStream is removed, anyone knows whats the alternative way ?

  


  Currently I am using the below code to generate video :

  


          if (packet->dts <= stream->cur_dts) {
        logD(RECORDER_TAG, "DTS not increasing, packet.dts:%d, cur:%d.", packet->dts,
             stream->cur_dts);
        ret = 0;
        av_packet_unref(packet);
        break;
    }


  


• ffmpeg - concatenate several videos with xfade transition

  8 mai 2021, par ilim

  I have N videos, and I'm using ffmpeg to concatenate them with xfade transitions between them. The video files are named as positive integers representing their order in the concatenated output, and none of them have any audio. In fact, each file just includes a different image with no animation that stays on screen all through that video's duration.

  


  I'm using a simple command I found in a response to an existing question to concatenate the first 2 videos :

  


  ffmpeg -i 1.mp4 -i 2.mp4 -y
       -filter_complex "xfade=transition=fade:offset=3.5:duration=0.5"
       1-2.mp4


  


  I planned to employ that same command for all the videos, each time appending a single video to the cumulative one produced so far, and producing an intermediary output to be used later.

  


  Specifically, I first concatenated files 1.mp4 and 2.mp4, and recorded the result into 1-2.mp4, which was produced correctly. Videos had the respective duration of 4 and 8 seconds, and the resulting 1-2.mp4 was 12 seconds long, with the transition occurring when it should.

  


  The problem started when I tried concatenating 1-2.mp4 and 3.mp4. I used the following command to generate a concatenation of videos [1-3].

  


  ffmpeg -i 1-2.mp4 -i 3.mp4 -y
       -filter_complex "xfade=transition=fade:offset=11.5:duration=0.5"
       1-3.mp4


  


  The video produced seems to be an exact copy of 1-2.mp4, and contents of 3.mp4 are not present at all in the resulting 1-3.mp4. Video file 3.mp4 was 3 seconds long, but the resulting 1-3.mp4 was 12 seconds long, just like 1-2.mp4 was.

  


  Apart from the input and output file names, both commands are the same. I was suspicious of having set the offset parameter of the transition incorrectly, but the first 2 files were merged successfully.

  


  I am at a loss as to what I'm doing incorrectly here. Is there a particular caveat of the xfade filter that gets problematic when used among 2 files with one of them already having that filter ?

  


  Any suggestions as to how I may debug or fix this behavior ? I'd welcome any alternative means of concatenating these (i.e., with some transition effects) in a simple fashion as well.

  


  I'm planning to use these commands in a Python script, so I'd appreciate any alternative solution not involving any gigantic commands or parameters.

  


  Just to be thorough, I should mention that I have ffmpeg version 4.3.1 installed via snap.

  


• Revision 2c886953d1 : Reinsert macro to fix issue 884. Change 72056 unfolded some macro definitions,

  2 décembre 2014, par Peter de Rivaz

  Changed Paths :
   Modify /vp9/encoder/vp9_mcomp.c

  
  
  Reinsert macro to fix issue 884.

  Change 72056 unfolded some macro definitions,
  but lost some alternative behaviour required for
  high bitdepth encodes.
  This causes the encoder to crash, see issue 884.

  Change-Id : I8ce4d73c9fe0a3c10ccb86fba210fabc8b2f0ccc