Lossless compression

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Lossless compression

Postby Suka Girl » Thu Apr 23, 2009 7:59 pm

Can anyone recommend the best way to test a codec to prove that it is truely lossless and frame independent?
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Suka Girl
 
Joined: 23 Apr 2009

Re: Lossless compression

Postby Zarxrax » Fri Apr 24, 2009 10:06 am

In avisynth:

source1 = AVISource("firstclip.avi")
source2 = AVISource("2ndclip.avi")
Compare(source1,source2)


Then play the avs script in virtualdub or something. The deviations should all be 0, and it should print a solid horizontal line along near the bottom.
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Zarxrax
 
Joined: 01 Apr 2001
Location: Concord, NC

Re: Lossless compression

Postby Zarxrax » Fri Apr 24, 2009 10:08 am

Also by frame independent I'm guessing you mean all frames are keyframes. To check this just load the clip in virtualdub and go to file>file information.
It tells you the number of total frames and the number of keyframes. These should be equal.
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Joined: 01 Apr 2001
Location: Concord, NC

Re: Lossless compression

Postby Suka Girl » Fri Apr 24, 2009 6:42 pm

Thanks Zarxrax!!! You rock!
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Joined: 23 Apr 2009


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