TMPGEnc: need help in encoding weird frame rates

[bluemist]

I wanted to encode from DivX to VCD format mpg, so I use the NTSC templates for VideoCD included on the TMPGEnc program. I once used the NTSC template (29.97fps) for all kinds of frame rates, but discovered that I was losing frames because the input and output frame rate isn't the same. I only discovered one remedy, in which I exclusively use NTSC for 29.97fps video and NTSCFilm for 23.976fps video.

Now my problem is that I now have weird frame rates (14.031, 15, 24, 23.98, 24, 24.031, 30) of some videos. Either template loses frames. Can you help me on how to encode this without losing any frames, then safely burn to VCD?

[bugster]

If your Divx has a framerate that is CLOSE to one of the standard framerates, just encode with TmpGenc using the nearest standard framerate. i.e 23.98, 24. 24.031 are close enough to 23.97fps for NTSC film and 30 is close enough to 29.97 fps NTSC so that you wont notice the difference. The 14.031 and 15fps videos are more difficult. My best guess would be to try encoding at 29.97 fps, which is close to twice the original framerate. Each frame will be duplicated by Tmpgenc, with just occasion frame drops to get the exact bitrate. This is probably the best you can do unless some one else knows better!

[bluemist]

I tried that method but it still loses frames. I tried to encode a 23.98fps video in the 23.976 template, but losing frames is noticeable at high motion scenes, or scrolling. I was wondering if there was any other workaround for it. Thanks anyway.

[bugster]

bluemist wrote:

I tried to encode a 23.98fps video in the 23.976 template, but losing frames is noticeable at high motion scenes, or scrolling.

I dont think thats a frame rate issue, it sounds more like a bitrate problem to me. VCD has a very limited bitrate and artifacts during high motion scenes (which includes scrolling) is common. To confirm if this is the problem try encoding one of your problem movies (perhaps the one with 23.98fps) at a much higher bitrate than standard, say 2500 or 3000 and see if the problem improves. Play back the resulting mpeg on your PC, don't burn to CD as it may not play.

If this fixes the problem you will need to consider XVCD or SVCD, depending on your players capabilities.