Why does quality suck when converted to Mpeg?

Grub

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Aug 30, 2002
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Hello folks...I'm pretty new to Video editing, but I have been reading every article I can on the subject. Right now I'm using VirtualDub to capture with my Leadtek winfastTV 2000 XP. When I capture I don't use any compression. I tried capturing in Huffy but the quality degraded too much. After capture, I play the AVI file and it looks great. However, when I convert it to MPEG for VCD it comes out blocky. It still looks OK, but if you unfocus your eyes on the details of the picture you can see that the video looks like its divided into a large gid of blocks. What is causing this? Is it my compression software (Ulead studio6), or is it something that is inherent to MPEG? Any advice or links would be appreciated.

The only way France is going in is if we tell them we've discovered truffles in Iraq. -Dennis Miller
 

namek0

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Oct 21, 2002
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See if you can capture straight to mpeg, if not, I could tell you a few places to go

And I've noticed when I convert an mpeg over 250 megs to avi, I get these nasty horizontal lines that buzz over the screen occasionally. When I get home, I'll see if I can post a link with a modded version of VirtualDub on it

It's all good ^_^
 

elzt

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May 10, 2002
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The blocky pictures from VCDs (usually appear when objects in picture are moving) is inherent to MPEG 1. There are some AVI-to-MPG conversion software that let you tweak the settings before doing the conversion in order to get the best quality picture possible. One of the software that I recommend using is TMPGenc.

Goto this link for details:

<A HREF="http://forumz.tomshardware.com/software/modules.php?name=Forums&file=viewtopic&p=32713#32713" target="_new">http://forumz.tomshardware.com/software/modules.php?name=Forums&file=viewtopic&p=32713#32713</A>
 

Grub

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Thanks guys...I'll give it a go...

The only way France is going in is if we tell them we've discovered truffles in Iraq. -Dennis Miller
 

scalar

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MPEG compression loses quality by default. It just tries to discard the less-noticed parts of the image. But if the compression level is too high (quality set too low), the discarded spots become more noticeable and the blockiness can be seen.

The only real way to eliminate the blockiness is to use a lower MPEG compression setting (higher movie quality). But more quality requires more storage space, and now your video may not fit on a single VCD.

So if you want a much better non-blocky video, your movies may need to be split across multiple VCDs to provide the extra storage space.
 

jammydodger

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Sep 12, 2001
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VCD quality is inherently bad. Whay dont you try and convert it to MPEG4? Or do you want to play it on a DVD player? If so convert it to MPEG2 and get a DVD burner.
 

Lazerous

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...and DVD-RW drives are dirt cheap these days. You can get a 16x for $60-$100.

I personally like to have my video's saved as AVI. Without the compression they are better quality and convert to DVD format nicely. When I use NERO to burn a new DVD creation it can actually improve the quality of some AVI's as well. A 700 mb AVI might take up 3-4 gigs on a high quality DVD.

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