Encoding tips for CD playback..

[cloudscapes]

Hi all,

Got one 720x480 documentary that I have trouble playing. It seems the keyframes are really far apart. So when I play it off a CD the disk stops spinning a couple seconds before the next keyframe. So then the video freezes (not the sound) for about a second and then it continues. Repeat every ten seconds. After about 10 minutes the sound is totally out of sync.

I've decided to re-encode it for better CD playback. I'll use VirtualDub and DivX3 or 4. When I re-encode, at what interval should I put my keyframes for optimized CD play on a 32x drive? Any other settings I should consider?

By the way, although my PC specs aren't top-notch, I've had no trouble playing other 720x480 (or whatever) fullscreen movies off a CD. High quality or low. So it's not a hardware issue.

Thanks!
-Etienne

PC specs, for what they're worth:
-Celeron 533MHz
-256MB RAM
-GeForce2 MX400 64MB
-SoundBlaster Live 5.1
-LG 8x4x32x burner

[Batman]

Your system specifications would not allow you to play such a "high resolution" file (at least I think so).

You should re-encode to a lower resolution (however this will result in quality loss) or reduce the bitrate.

If you don't want to re-encode, here are some suggestions:

1) use a less cpu intensive player such as BSPLAYER or GDIVX
2) reduce desktop area to 800x600 or if neccesary 640x480
3) reduce colour to 24 bit, maybe 16 bit
4) use a hdd instead of a cd drive.
5) close all background apps

Hope this helps

[cloudscapes]

But as I mentioned in my post I play other 720x*** from CDs just fine! Full framerate and fullscreen at 1240x1024. This is the only one out of about 20 with similar resolutions and quality, so it has to be an encoding issue.

I will follow your tip to re-encode at a lower resolution though. Probably 640x400. Just need to figure out if I should have a lot of keyframes or little.

[Batman]

By reducing the resolution you lose quality

You could also re-encode by increasing the number of key frames. Just another option you may want to look into.