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• FFMPEG MP4 from a m3u8 stream results in a few black frames

  14 avril 2020, par roosevelt

  I'm noticing an odd behavior and not sure how to tackle it through FFMPEG. Basically, I'm downloading some ts files from a stream and making an MP4 out of them. I don't need to encode them since they are already encoded.

  



  Here's the command :

  



  ffmpeg -nostdin -y -ss 3 -i https://d2nvs31859zcd8.cloudfront.net/d33af82762361135e8ba_yassuo_37349116016_1403122741/chunked/index-muted-EIVFBWYS1V.m3u8 -t 50 -c copy Test.mp4


  



  If I run the MP4 file in Quicktime player, it seems like there are one or two black frames in the beginning. How do I get rid of that using the above command ?

  



  I also tried downloading the .ts files and concat them via FFMPEG. But the result is the same. First few frames are black.

  



  ffmpeg -nostdin -y -i "concat:0.ts|1.ts|2.ts|3.ts|4.ts|5.ts|6.ts" -c copy Test2.mp4


  



  Seems like VLC doesn't show the black frame but it's apparent on the Quicktime player.

  



  Thanks

  


• ffmpeg - how to add text on black background at end of video for 10 sec ?

  3 octobre 2015, par jamie

  I have some mp4 files I’d like to add some white text reading something like

  "StackOver Flow Rules see more at www.stack.com/324324 bla bla and some more words here !"

  To the end of the videos on a black background that last 10 seconds.

  How would I achieve this with FFMPEG ?

• Is there a way to detect black on FFMPEG video files

  22 novembre 2019, par A Person

  I am trying to run a QC check on my video files.

  I know that there is a way to detect black frame or audio loss in a video file. Can anyone help me with how the syntax is written ?

  I have tried doing the following but I am having issues as I do not know how to tell from the output.

  ffmpeg -i inputfile.mxf -vf blackdetect=d=0.1:pix_th=.1 -f rawvideo -y /dev/null

  Also is there ay ways to check if I have any packets that are in error by using ffprobe or ffmpeg

  I also do not understand waht this 0.1:pix_th=.1 is doing ?

  EDIT* :

  I have used this command now

  ffmpeg -i 01.mxf -vf blackdetect=d=0:pix_th=.01 -f rawvideo -y /NUL

  this gives me

  [blackdetect @ 000001a2ed843740] black_start:0.04 black_end:2

  black_duration:1.96

  [mpeg2video @ 000001a2ed86efc0] ac-tex damaged at 45 304.08

  bitrate=829328.3kbits/s dup=1 drop=0 speed= 5.6x

  However, the actual video has more than this for the black frame.

  is there a way to tell it to continue looking at the video and get all black frames, not just the first instance.