Recherche avancée

Sur d’autres sites (10933)

• Timing Issues When Muxing Audio and Video with libav

  21 mars 2014, par Stephen H. Gerstacker

  I have series of encoded packets, H.264 video and AAC audio. As they're coming on, I'm writing them to a video file, using av_write_frame.

  Given the following situation in a row

  • 10 seconds of video, then
  • 10 seconds of video and audio, then
  • 10 seconds of video.

  Everything muxes fine and when played back via VLC or QuickTime, everything looks good. If I play it in Windows Media Player, the audio is played immediately.

  It seems I'm doing something wrong, but checking the PTS of the audio stream packets, they are set to 10 seconds based on the time base of the audio stream.

• scalability issues with video encoding on webserver

  2 janvier 2013, par Prasanth

  On a web application that im creating the user is allowed to upload a video. The video is converted to x264 using ffmpeg for iOS playback. So if there are too many users thats going to kill the web server.

  I'm thinking about something like this. Have a few encoding servers for the application and the application on receiving the video file uploads to any one encoding server and the encoding server encodes the video and uploads it back to the web server.

  Are there any other solutions preferably which wont increase the response time for the user ? The user has to see the preview of the video as soon as the upload process finishes.

  The client does not want any 3rd party video encoding services. We have negotiated this many times but they do not want this.

• Issues with VLC Displaying FFmpeg Stream from NamedPipeServerStream : Freezing and No Display on Late Start [closed]

  15 juillet 2024, par Roy Raihenshtein

  Disclaimer :

  


  This is a follow-up question to :
Streaming an updating folder of images with ffmpeg without restarting the script.

  


  After implementing my NamedPipeServerStream as a dynamic input (which works great), I've encountered two issues :

  


  If I don't start VLC network streaming before the application that contains the pipe, VLC will not display anything.
After roughly 30-40 seconds, the output image freezes for 40-70 seconds, then becomes active again for about 20 seconds before freezing again.
Here is my FFmpeg command :

  


  ffmpeg -f image2pipe -vcodec mjpeg -framerate 8 -pixel_format bgra -video_size 2048x2048 -i \\.\pipe\imagePipe -b:v 512k -bufsize 1024k -c:v libx264 -preset ultrafast -tune zerolatency -crf 35 -pix_fmt yuv444p -f mpegts udp://127.0.0.1:8554?pkt_size=1316&buffer_size=64k


  


  Additional details :

  


  


  • The pipe is being filled at a rate of 40 fps.
Each frame takes 16 MB.

    


  


  • Is it possible that I can't rely on the output when I use my machine as both the input and output ?

    


  


  


  I'm using .NET Framework 4.7.2 and WinForms. For playback, I use the VLC application.