Fast movement sometimes = small blocks on mpeg?

[apollo1980]

Hi all.

I have been burning DVD+WR's without a problem, except I sometimes see, during very fast movement of a person, for example, small blocks of pixelazation around the person in the video if they do a very rapid movement, like, say, turn their head real fast.

I don't convert an avi to mpeg without a minimum of 4000 for the bitrate. I've got a conversion I did with a bitrate of 5500, and I still have the problem.

I am using the following:

Computer Hardware:
P4 2.2ghz
512 megs RAM
Xtera Geforce 4 Ti4600 128megs RAM with VIVO using S-Video
HP DVD 100i DVD Burner
Western Digital 120mb ATA100 7200 RPM Hard Drive

Computer Software:
Windows XP Home SP1
WDM Drivers that came with my Video Card
Virtual Dub, latest version, to caputre video
Tmpgenc, latest version mpeg2 ability, to convert video
Dazzle DVD Complete, to authorize DVD's

Stand alone DVD players for playback:
Pioneer DV-414
Pioneer DV-341

Regardless of kicking up the bitrate, I still sometimes get the pixelazation effect when there is a rapid movement.

Is this a bitrate issue, or is there something else that I need to do?

Thanks in advance.

[bunyip]

You don't mention the condition of the AVI. Are you capturing at a high enough quality not to have the pixelation introduced at capture time?

[DJRumpy]

Exactly. What type of input is your source material? It's possible the pixelation is in the source material itself (common on lower bitrate DivX/XviD). If your source is CAM, or a noisy analog capture (like VHS), then it could be simple bitrate shortage. If your source is cam, you should consider CVD resolutions, instead of full D1/CCIR-601. The reduction in size will make much more bitrate available to your video.

If your source is noisy, you should clean it first with a good temporal smoother, or 2-d filter, before compressing to MPEG. You should also use multi-pass VBR, as the additional passes will help with bitrate allocation on difficult (high motion) scenes.