camera or codec capture problem? video stutters

n201cm wrote on 5/3/2004, 7:42 PM
Win2000, VV3...

Sony TRV900 camera

DV played back on the camera to a TV monitor looks fine and seems to play perfectly smoothly. DV video captured to my computer via VV3 shows a disturbing pulsing effect almost like a flicker. No frames were dropped during capture...It only seems to show on moving scenes where the motion seems to stop/start rapidly about 5x/sec. At first I though this was related to my computer avi playback only. But if I write an mpeg2 DVD file and play the DVD back though a stand alone player the effect is even more pronounced. I tried writing at a high constant bit rate but get exactly the same effect.

Might there be something wrong with the capture codec? I'm just guessing...

Any help is much appreciated!

Comments

Spot|DSE wrote on 5/3/2004, 9:08 PM
First, there is no codec at capture unless you are using an analog converter card that isn't OHCI.
Second, much of what you are describing sounds like interlace flicker, which wouldn't show up on a television/stand alone unless you'd messed with the fields on render. A computer monitor will nearly always show interlacing artifacts, because it's a progressive scan display vs interlaced display.
Bitrate won't take away interlacing artifacts. Are you playing back on a progressive scan player/television?
n201cm wrote on 5/4/2004, 3:29 PM
Yes, I'm playing the video back on a progressive scan DVD player. Would that help or hinder the effect you are describing?

I have not messed with the fields in the render, just used the standard template for NTSC DVD video.

The video in question was copied from a VHS tape using the s-jack on the TRV900. I fed this video directly to the computer via firewire and the VV capture utility. Then the cionversion to DVD video shows this stuttering effect on both the computer and TV.

Is going through the camera this way the best way to get a clean signal from a VHS tape on to the computer. I do have a Matrox card that will capture but I've never tried using it as I thought for sure that capturing DV was fine, and that by stepping up to a higher resolutuion (the TRV900) I shouldn't lost quality. But I'm not so sure. The DV video doesn't stutter, but it does not look as sharp as the original VHS tape and that surprises me. It's quite contrasty and rich in color...just soft in focus. Any ideas about either of these iSSues?
Thanks for your help!

Peter