Wrong frame rate in VirtualDub

[Shuggie]

In my continuing battle to produce an SVCD my DVD player will play I've hit this problem.

I have a Hauppage WinTV 2000 card. If I use the bundled software I can capture MPEG2 at upto 12Mb/s. I was capturing at 2Mb/s but Nero complained the resolution was non-standard. Since I can't do custom resolutions I tried capturing using VirtualDub and the huffyuv codec from this site.

Here's the problem - even though I specified 25 fps (PAL) the actual fps was ~17. The resulting MPEG file was in 'slo-mo' with no sound. It seems like the computer wasn't fast enough to process the information at 25fps. But if that's the case how come the bundled software can do it?

Am I using the wrong codec?

[Dman65]

Can you supply some details about your setup? Processor speed, drive types, settings used to capture, etc.

[hitechjunkie]

there are a lot of factors that affect capturing. capturing raw avi, rgb24, 640x480, 30fps, no compression, requires a sustained datarate of 26MB per second. the only way to capture at this datarate is by using a raid (SCSI) or psuedo-raid (FastRaid) setup of disks. if raid is not an option, you can try one or more of the following to reduce the sustained datarate required and ultimately eliminate dropped frames:

- switch from rgb24 to yuv2
- reduce the resolution of 640x480 to 480x480, 352x480, 352x240 (assuming NTSC)
- use compression on capture, huffyuv (lossless), picvideo mjpeg (lossy)
- reduce the framerate

then there are other factors which can also affect the capture:

- CPU speed (when using compression on capture, is it fast enough to compress the larger resolutions at the higher framerates?)
- disk speed (5400rpm vs 7200rpm, fragmentation, etc.)
- system load (are there any background tasks running?)

if tweaking your system config does not get you better captures, you can also upgrade:

- faster disks
- faster CPU
- capture card with built-in MPEG compression

just some things to consider...