Extract audio from video using Mplayer:

  • mplayer -ao pcm:file=filename.wav video.avi

Play audio while playing video:

  • mplayer -audiofile file.mp3 video.avi

Using FFMpeg (-y is to overwrite file), merge audio and video:

  • ffmpeg -y -i audio_to_merge.mp3 -i video_to_merge.avi -vcodec copy merged_output.avi

Merge video and audio with Mencoder:

  • mencoder -oac copy -ovc lavc -lavcopts vcodec=mpeg4 video_to_merge.avi -audiofile audio_to_merge.mp3 -o merged_output.avi

From OGMTools, merge OGG Vorbis audio and Theora Video:

  • ogmmerge -o merged_output.ogm audio_to_merge.ogg video_to_merge.ogv

Convert video to images using FFMpeg (24 frames a second):

  • ffmpeg -i video.avi -r 24 -f image2 image%03d.jpg