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It all depends on the DivX -- as MPEG-4 (Divx) and MPEG-2 (DVD) are both lossy formats, the thumb of rule applies: shit in, shit out.
In other words: whatever the output format, its quality can't exceed the quality of the input material. So, if the DivX is crappy, it can't get -- in any possible situation, ever -- better from that by converting it into a DVD. Instead, the quality drops always when converting from DivX to DVD -- as DVD provides more bitrate to play with, typically the drop between DivX and DVD is unnoticeable. But the quality of the resulting DVD doesn't have anything to do with the quality of the original DVD video that was once converted to DivX -- only quality that matters when converting "back" is the quality of the DivX :-)
Let's say that we do several conversions for the video, from one format to another and then that result again to another. Let's agree that in here, one means the worst possible video quality and ten means the best possible video quality:
original DVD, quality 10
lets convert it into a high bitrate DivX. Let's say this resulting video has a quality level of 8.
Now, whatever format we convert the DivX to, it can't ever exceed quality of 8. Ever. So, we do a high bitrate conversion with all the magic we know from DivX (of high quality, "8") to SVCD.
Now, lets assume the quality of this resulting SVCD weakened only a little bit, as we're so darn good encoders. It is now quality of 7. We put this to our granpa's machine and run a P2P on it and distro it to our 3 million closest friends.
One of them decides to convert the good quality SVCD he got from P2P to a DVDR. Now, no matter what encoder or snake oil he uses, best quality he can ever achieve is "quality 7". And so on..
Hope I didn't confuse everybody now :-)
This message has been edited since posting. Last time this message was edited on 13. September 2004 @ 12:44
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