VCD to KVCD bitrate - keep the VBR between 300 and 2300?
 

I have converted downloaded episodes in VCD format to KVCD, because I like more than 1 episode on a CD.

I was wondering: because regular VCDs have a cbr of 1150, is there any use to keep the VBR between 300 and 2300, or could I change the upper variable to 1150, thinking that there isn't more information anyway?

:?:

Re: VCD to KVCD, bitrate
 

Not really. This is what happens. Your encoded material, from whatever the source was, has now been re-encoded to mpeg.

The material has macro blocks, because mpeg is a block based scheme, even if you can't see them.

Now when you encode this material again, you are adding your new macro blocks to the static blocks already in the material.

If your bit rate is 1,150Kbps, just like the original encode, wherever you have blocks on your source, because the bit rate wasn't high enough in the original encoding say in a high speed scene, you will also be generating a "blocks over blocks" effect. So the result is worse than the original.

So you have to keep your bit rate, or should I say "sampling bit rate" higher than the original, to minimize this effect.

This is similar to a basic rule in audio digitizing. You always sample at least twice the frequency of the source you are digitizing.
If you don't, you get distortion. In mpeg video, you get blocks.

But remember that your target will look no better than the original, and probably worse, because of static macro blocks on your source plus the new generated macro blocks.

Result: aligned + unaligned macro blocks = 8O :P

I hope this explanation makes sense 8O

kwag

Thank you for the explanation.

The episodes I've done so far (at 300-2300 VBR) do look better and are smaller, but that's mainly because the original captures were way too dark and my Tv somehow is unable to make them better (they just become 'grayer'). Using the gamma and brightness controls in TMPGEnc I get better looking episodes, and I can fit 2 (sometimes 3) on one CD.

On better looking sources I still get the gain in file size, and I find the results very accepable.

I guess different people get different pleasure from your templates :)