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Monday, January 21, 2013

Video on Linux?

A few more adventurous officers got a grant to buy a Linux based workstation. They figured that since they were downloading from Linux based DVRs, they should have a Linux based computer. But, much to their dismay, the video that they downloaded from the DVR didn't work on their Ubuntu box.

As a general rule, viewing video files in Ubuntu requires two separate pieces of software:

  • A video-playing software package
  • A video-decoding software package

The video-decoding software package tells the video-playing package how to read and interpret the video file. Hopefully, by now you know that the decoding software is called a codec. Usually, each codec decodes a single type of video file. Ubuntu contains only the codec package for decoding OGG video files. Viewing any other type of video file requires downloading a different codec package. This is where things get messy.

The MPG video file format is by far the most common video format in use, both on the Internet and in many digital movie cameras. It provides good-quality video with relatively small file sizes by using patented compression algorithms. Unfortunately, because of the patented algorithms, MPG is a licensed product, which is a bad thing in the open-source world. Reverse-engineered codec packages are available that can decode MPG video files in Linux systems. However, these packages are not legal for use in some countries.

Add to this the problem of using un-licensed or quasi-legally obtained software in your case work. Do you want to answer questions about the legality of how you obtained your codecs from an Estonian hacker's web site?

For the power-user, having a Linux based workstation can be an advantage. But, most DVRs output a file that is meant to be used in the Windows operating environment.

One of the things that Amped FIVE users know is that FIVE automatically chooses the appropriate decoder - taking out the guesswork. And, to top it off, the choice is documented in your report. How cool is that?!

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