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• ffmpeg settings for high quality youtube videos [migrated]

  1er avril 2018, par pb.

  I am trying to record short video of my desktop and upload it to youtube.
  The problem is that every time when I upload it to youtube or even dropbox (as video), the quality is much worse.

  My ffmpeg execution :

  ffmpeg -f x11grab -s 1366x768 -r 30 -i :0.0 -codec:v libx264 -crf 10 -bf 20 -flags +cgop -pix_fmt yuv440p -movflags faststart help.mp4

  based on :

  ffmpeg -i <input file="file" /> -codec:v libx264 -crf 21 -bf 2 -flags +cgop -pix_fmt yuv420p -codec:a aac -strict -2 -b:a 384k -r:a 48000 -movflags faststart .mp4

  which I found here

  Original file (.zip) :
  https://www.dropbox.com/s/xlkr83rkqfxon23/help.mp4.zip?dl=0

  File after upload to youtube :
  https://www.youtube.com/watch?v=ewEUgpXOpmg

  As you can see, I loss quality after upload to youtube.

  Could you help me ?
  How should I choose the appropriate parameters to record and upload high quality video ?

• How to stream to YouTube from an X server using DISPLAY with ffmpeg ? [closed]

  21 avril, par Ahmed Seddik Bouchiba

  I'm trying to stream my desktop (from an X11 session) to YouTube Live using ffmpeg. I'm running this on a Linux machine with an active X server, and I set the DISPLAY variable accordingly (:0 in most cases).

  


  Here's the ffmpeg command I've tried :

  


  ffmpeg -loglevel info \
    -probesize ${PROBESIZE} -analyzeduration ${ANALYZE_DURATION} \
    -f x11grab -video_size ${VIDEO_SIZE} -r ${FRAME_RATE} -draw_mouse 0 -i ${DISPLAY} \
    -f alsa -i default \
    -deinterlace -vcodec libx264 -pix_fmt yuv420p -preset fast \
    -r 30 -g 60 -b:v 2000k -bufsize 4000k \
    -acodec libmp3lame -ar 44100 -b:a 128k \
    -map 0:v:0 -map 1:a:0 -vsync 0 \
    -f flv "${RTMP_URL}" &


  


  Environment variables are set correctly (DISPLAY, VIDEO_SIZE, FRAME_RATE, etc.), and I replaced $RTMP_URL with the correct YouTube RTMP endpoint (e.g., rtmp ://a.rtmp.youtube.com/live2/). But nothing seems to work — the stream never starts or appears on YouTube, and sometimes I get timeout or "connection refused" errors.

  


  I've checked :

  


  That I'm logged into an active X session

  


  That I have access to the display (even tried xhost +)

  


  That ffmpeg has access to ALSA (sound seems okay)

  


  Questions :

  


  Am I missing something in my command ?

  


  Is there a better way to stream both screen and audio from an X server to YouTube Live ?

  


  Could this be a codec or YouTube-specific format issue ?

  


  Any help or working examples would be really appreciated. Thanks !

  


• youtube-dl streaming to pipe, how to add container

  24 décembre 2017, par MetNP

  I use this command on raspberry-pi :

  youtube-dl -o- [youtubeurl] | omxplayer --no-keys pipe:0

  and it works great for 50% of youtube content. For non-working videos, omxplayer just won’t play it. It is not raspberry nor omxplayer specific problem. All players are ffmpeg based and for those videos the same problem can be achieved on any platform with ffplay or ffmpeg live transcode...

  When i download that kind of video separatelly :

  youtube-dl -o name.mp4 [url]
  
  ffplay name.mp4                   ... works OK
  
  cat name.mp4 | ffplay -           ... does NOT work (input stream not recognized well)

  Reason for this problem is well explained here. MP4 by itself is not good enough for streaming, and i want just to envelope it inside some TS or MKV or any container that will help player.

  Does someone have an idea how to do it ? Can youtube-dl be forced to do it itself, and can some middle ffmpeg command helps ?

  update : thanks to directions from Mulvya comment, it seems that all video works well with -f mp4 addition :

  youtube-dl -o- -f mp4 [youtubeurl] | omxplayer --no-keys pipe:0

  selecting specific format like -f 135+140 breaks pipe usability, and will not work except with some possible code changes. Until i reach some other problematic video content, it seems that -f mp4 solved everything.