Burning in subtitles without losing quality

[retrosteve]

Okay, I've got this .avi file. It's in French, so I want to add the subtitles in English. I've got the .sub file, and it works fine. I can use mplayer or ffmpegX to view the file with subtitles and all is ok.

But

The file is a nice quality AVI. FF sez it's 3VID, 576x240, 24bpp 25 fps 174 kbyte/sec.

All I want to do is burn the subtitles onto the image without losing quality, so I can burn the movie onto a CD with subtitles. Ideally I'd like them in the letterbox black bars, but I'd accept them in the image instead. I don't really have a preference of format, as long as the quality is good and it's well supported by commercial players.

I tried several times and failed to do this. I can either try leaving all the audio and video settings to change as little as possible, and then subtitles are disabled, or I can start changing the settings to convert to,say, mp2. (As mentioned in the manual, apparently the only supported format for burning subtitles), and then the subtitles get burned, but with 3 problems:
1. No sound on the output
2. Horrific loss in picture quality
3. subtitles are writ large across the lower third of the screen
Also, it takes over 24 hours to do such a conversion on half a movie!

I can't help thinking I'm missing something easy. Can someone please set me straight?

Thanks,
Steve

[major]

Burning subtitles in the image only makes sense for use with playback devices not supporting subtitle rendering (like CVD or SVCD).

For DivX files, players can render subtitles at playback time, so subtitle burning at encoding time is not supported. You should just put the .avi and .sub files together in your CD.