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core concepts: bitmap, PCM, frame rate, sampling rate, frame size, data rate, compression, lossless vs. lossy compression, codecs, spatial compression, temporal compression, keyframes, VBR, 2-pass encoding


Examples of appending images in bash, including a simply "flow" layout algorithm... BashAppendingImages

Encoding Videos (including flash flv's) to DIVX/AVI with mencoder

Basically to encode any format that mplayer understands to a divx file (which is a version of mpeg4, and typically stored in an "avi" format file), you use something along the lines of:

mencoder -oac mp3lame -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=600 -o newmovie.avi sourcemovie.flv

This specifies the "libavcodec" (lavc) to do the video compression, and options to that (separate) library are given as "lavcopts". To, for instance, specify an output frame frame (ofps) of 15fps *and* to limit the maximum number of frames between keyframes to one second (15 frame thus), you could use:

mencoder -oac mp3lame -ofps 15 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=600:keyint=15 -o newmovie.avi sourcemovie.flv

Images to movie

with ffmpeg

ffmpeg -y -r 3 -b 1800 -sameq -i frames/%06d.png foo.mp4


with mencoder

mencoder "mf://*.jpg" -o movie.avi -ovc lavc -lavcopts vcodec=mjpeg

source: also:

Movie to images

with ffmpeg

ffmpeg -i movie.avi -f image2 -y -r .01 -an frame %06d.jpg
ffmpeg -i FILE0007.MOV -f image2 -y -an frame%06d.png
ffmpeg -i -an -y -t 0:0:0.001 -f image2 poster.png
ffmpeg -i -an -y -ss 0:01:30 -t 0:0:0.001 -f image2 frame.png


mplayer -vo png rearwindow.avi

Important command line tools



Other useful (GUI) apps

Audacity, Kino


older page