I have an avi file that I want to make an svcd, but to do so I have to convert it to mpg format, is this correct? When I try to do this, no matter what program I have used (it's been many, inlucding the popular tmpgenic) there is always a large loss of quality in the end product. I believe the avi is encoded in xvid. So my question is if there is anyway to convert it without such a large loss of quality, or if there is a better way to convert it to svcd. Thanks for your help.

The short answer is 'probably no', because much of the quality has already been lost in the original XVID compression.

Depending on what you will play the SVCD on, it might help a little to create a high-biterate svcd (called an xvcd). For example, you could encode at 3500kbps instead of the 'spec' 2600 - many but not all standalone players, and almost all software players, are likely to handle that.

Actually, the quality is excellent in the avi format, but even encoding at extremely high bit rates hasn't helped in the mpeg format. I'm wondering if part if not all of the problem is the resolution. None of the programs I used let me set the resolution higher than a 700some width, so it has to encode in a low-ball resolution. Is there a way to encode at higher resolution without making a dvd-size file (I don't have a dvd burner)?

You can't change the resolution of SVCD without making a non-standard disc which may not work.

NTSC SVCD: 480x480
PAL SVCD: 480x476

You also probably need to split the movie over 2 or 3 discs because xvid / divx movies are normally much more compressed than SVCD. The maximum standard SVCD bitrate allows 40 minutes per disc but you may increase it up to 60 minutes per disc by lowering the bitrate but then you also lower the quality.

If you still want to experiment with non-standard resolutions then try to lower the resolution to 352x480 or 352x576 because then you get more bitrate per pixel and the quality may improve. You can also try some smoothing filters.

But you'll always loose quality when you convert to SVCD.

I have converted many xvids and divxs to SVCD and even VCD with good quality.

If the xvid source you're starting with is good, then you should be able to convert to SVCD without serious loss of quality.

TMPGEnc is not a great tool for such things, but you should be able to get decent quality out of it.

Now if you're trying to squeeze this all onto a single cd, then that could be part of the problem.

Try going in at 2500 CBR including audio, and as previously suggested, split the file over several CD's if necessary.

mark