picture jerky after converting to vcd format...what causes this?

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I capture using AIW 128 PRO 32MB card using MPEG-1 at 480X480 resolution at 3.5 Kbps bit rate with "deinterlace" feature ON and do not get any dropped frames or <1% dropped frames. When I view the capture, there is no "jerkiness" to the picture. I then encode using TmpGenc to VCD compliant 2.0 with 1.15 bitrate setting and 354X240 and the picture becomes jerky once in awhile. When I encode, I only use the filters for clip frame (to output to VCD resolution at NTSC), deinterlace, color correction, and noise reduction with TempGenc. I don't get jerkiness when I leave resolution at 480X480, but when I encode it to use full screen (NTSC), I get a movie that sometimes seems that I purposely made it slow motion (jerkiness movement)!...help please!.. Is it the bitrate being set too high that causes this? I play the original capture and it does not jerk, but the encoded one for VCD compliancy has this "jerkiness" or "dropped frames"? Please advise as to how to prevent this from happening. I am running a Celeron at 900Mhz with 256 SDRAM and a 5400rpm UDMA/33 hard drive with 6.5G free. I am upgrading my hard drive to a 7200rpm 40G first and then move up to a P4 1.4Ghz processor in the near future. Any advise would be appreciated. Thanks in advance.

-- Ray Banez (rayban@ev1.net), January 15, 2002


Is it jerky when immediately playing the finished encoded MPEG file or the VCD created from it??

-- Mehmet Tekdemir (turk690@yahoo.com), January 16, 2002.

The encoded mpeg file from TMPGenc has the jerkiness already. The original capture file which is 480X480 mpeg from my AIW 128 PRO card does not have the jerkiness. I was wondering if dropped frames during capture can cause this on the final mpeg file? When I play it from the VCD, it is jerky as well...just like on the enconded one by TMPGenc. Do I need to capture the original using a lower bit rate? Which filters do I avoid using to prevent this on TMPGenc? Thanks for any input.

-- Ray Banez (rayban@ev1.net), January 16, 2002.

Use flask encoder with deinterlace facility with manaual calculation of the NTSC ie 29.5 fps. I feel that this is the easiest way to encode the DVD.

-- (vigneshraj@msn.com), January 17, 2002.

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