Notes on Linux

One of the most popular uses of the internet is viewing videos on youtube. The 10 minute limit is rather short and often users will upload videos in parts to comply with the time limit. Let's say the video you're interested in is in three parts. One can download all the parts via a python script and use mencoder to combine the parts together:

mencoder part1.flv part2.flv part3.flv -o all.flv -ovc copy -oac copy -of lavf -lavfopts format=flv

Another interesting problem I came across was a video on VHS that was recorded on it's side. The reason this was done was because it was a recording of an upright video game and the display was higher than it was tall. The bash script to record from VHS to the computer is here.

Then I used mencoder like so:

mencoder -vf rotate=2 -o tempest-rotated.avi -oac copy -ovc lavc -lavcopts vcodec=mpeg1video tempest.avi

One can also use mencoder to take a bunch of png files and make a video out of it:

mencoder "mf://*.png" -mf fps=10 -ovc lavc -o file.avi

This only scratches the surface of what mencoder can do, but it's definitely a useful tool.