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junglemike
23rd February 2004, 00:48
Hi people.
I have a little trouble capturing video. maybe anyone can give me a tip.
I am capturing small clips in full pal resolution: 768x576@25fps.
I have p3-750/512mb sdram. 40gb wd 7200. Win2000. i have BT848 card. I am using IUvcr. I know that in guide it is recommended to use VirtualDub. But i can't VD is a really cool program. I use it for everything. But i have analog cable-tv. So in VD i can't choose any channel (channel frequency). I capture in huffyuv or leseless jpeg codec. The problem is the following: Although i set a high priority to IULab's Iuvcr, anything running in background will result in dropped frames. And even if i close all the rest of process, still sometimes there're little of dropped frames, which cause to a/v desync. The only way to make this work - if i run a full defragmantation on disk, make reboot, kill all other processes and than, maybe it will be able to capture all frames.

My question is: Maybe there's some setting in windows which will encrease read/write buffer to bigger value, say, 100mb, Or maybe some program can do this? I tried other programs for capuring. The picture is approximately the same.
Thank you

rfmmars
24th February 2004, 08:07
At full PAL you may be pushing it with that resolution. I am trying to remember back when I was doing .AVI capture facing the problems you have. For me I was doing NTSC 640x 480 29.97 at a data rate of 4200 bps using a DC30 board with no dropped frames.

I was using a AMD 233 mhz 64 meg ram and a IBM Datastor IDE a ATA 66 drive. First you don't want any read-write cache at all. Change that in the bios.

Make sure the DMA is turned on for your hard drive. There are varius settings also in the bios for the hard drive, so it's trial and error. Don't slave a CD or DVD to the capture drive. Nothing is to be running in the background.

The best capture program was AVI-io, you can download a demo copy, but I see that you are using you card's tuner. I dont remember if it will allow you to set the channels. Does your card have video inputs, and if so, could you use your VCR video output to feed the card?

Richard
photorecall