I have been downloading quite a few music videos lately, and I sometimes need to re-encode them to a vcd compliant format. The only problem with this is that mpeg artifacts tend to build up. Is there any way to avoid this? I've been just using Xing to re-encode them so that they are vcd ready. Any suggestions for software, or any little secrets that anyone knows out there?

This would probably also help with my re-encoding of downloaded movies too.

-- Chris Wroblewski (strudelc@home.com), September 28, 1999

Answers

Because of the very nature of the MPEG1 standard, the problem that you mention is mathematically unsolvable. Every time you code an original video to make the first .MPG, you get a stream that is very much like the original movie PLUS the MPEG artifacts that you mention. When you attempt a 2nd. compression, this rule applies all over again: because the encoder can't know that the artifacts you are inputing are not part of your original video, it codes them as well, thus obtaining at the output: original video + 1st MPEG artifacts + 2nd ENCODING (new ones) artifacts. This does apply if you attempt to reencode with same parameters as original, and become worst when this parameters (bit-rate/packsize) are changed, which is your case I guess!

-- Matias Petrella (petrellm@telefonica.com.ar), September 30, 1999.

I been working on this problem also and have come up with a work around. In my project I wanted to compile a VCD of video game openings fmv's (full motion video). All of these have been encoded/compressed with some form or another for play back on PSX or Sega Saturns. After pulling them from the game discs I converted them to avi file format. Since they were digital files I didn't have to de- interlace them. Thats the background of the project... on to the fix.

1. In Media Cleaner Pro re-save the file as an non-compressed avi, but blur it and set noise reduction. This averages out the artifacts. I used the medium setting and it got rid 97% of the artifacting. Then encode as usual. The drawback of this technique is the resulting file size of the re-saved blurred avi.

2. Use the noise reduction in the stand alone version of the Panasonic encoder. It cleans it up pretty good and you don't need to generate a a blurred avi file but the quality not as good as method 1 or 3.

3. By far the best results came with the MegaPeg stand alone encoder. It had sub pixel blurring and a very good noise reduction capabilities. The plus is you don't have to make a second avi before encoding. The bad part is that MegaPeg costs 500 bucks.

I hope this helps

-- Rogan Josh (the_fool99@hotmail.com), February 18, 2000.