Recherche avancée

Sur d’autres sites (14074)

• FFmpeg screencast recording : which codecs to use ?

  24 avril 2013, par mkaito

  I've been experimenting with recording screencasts using FFmpeg's X11grab module, which has worked more or less fine so far. I understand that a/v encoding is a complex process with many fine details, but I'm doing my best to learn.

  I'd like to do "lightweight" recording of a video stream, that puts as little strain as possible on the system while the stream is being recorded. I record two audio streams separately with pacat and sox. Later, the whole thing is filtered, normalized, encoded, and combined into a Matroska container.

  Right now, I'm having ffmpeg record a rawvideo stream to be fed to x264's yuv4 demuxer. I experimented with ffv1 and straight x264 recording before. My system can't handle real time encoding with x264 on the settings I want for the final stream, so I have to recompress separately once the recording is done. I've found that ffv1 gives me terrible frame dropping, and yuv4 too, but less so. I suspect this is due to hard drive speed, even if I'm sitting in a SATA3 Caviar Black that's being used exclusively to hold the recorded data.

  The question is, which combination of video codecs should I look at ? Record straight in x264 and recompress to "better" x264 later ? Raw video, then compress ? How would I go about pinpointing issues such as the frame drops I've been experiencing ?

  EDIT : This is the ffmpeg line I currently use.

  ffmpeg -v warning -f x11grab -s 1920x1080 -r 30000/1001 -i :0.0\
  
  -vcodec rawvideo -pix_fmt yuv420p -s 1280x720\
  
  -threads 0\
  
  recvideo.y4m

• ffmpeg setting up in wamp (in local) OR server

  5 janvier 2013, par Rahul TS

  can anyone explain the procedure of installing ffmpeg in wamp.
  I got an answer to my previous question on ffmpeg and wamp that we have to interface the ffmpeg (here) with wamp.

  I need to have a step by step process of how to do this, as I am confused with the interfacing little bit

  I also want to know what is a way to install this ffmpeg into the server, or the procedure to do before we do the encloding procedures

• How to suspend ffmpeg file reading ?

  6 décembre 2012, par jAckOdE

  My ffmpeg-based player plays a mpeg-ts file that downloaded from a server. I want my player be able to play the video file even it is being downloaded.

  There is no problem if the download speed is faster than reading speed, otherwise my player crashs.
  My question is that is there anyway to suspend ffmpeg file reading to wait for data available to proceed ?