capturing with AVI_IO : dropped frames

[filipdebie]

hi,
I always use AVI_IO to capture from my Hauppauge WINTV pci card.
I use the PICVideo MJPEG Codec at quality 19 and format 352x576.
With these settings I have max 1 or 2 dropped frames/hour at 25 fps.
I convert the AVI to VCD with TMPGENC and I have always good results.
The strange thing is that when I recently tried to capture from a VHS-C tape,
there were nothing else than dropped frames.
When I put the format on 720x576 , then I had no problems anymore
Where is the logic of this ? A bigger format an less dropped frames ???!!!
(Why can I not capture from a TV signal with this format without losing frames)

[travismoran]

My thoughts would be that it is your capture card or something else besides AVI_IO.

Oddly enough I use AVI_IO & PICVideo MJPG codec at the same setting you do and I have an occasional drop every hour or so. But it is consistent with whatever resolution I use. (I only use 3 resolutions: 352x480, 720x480 & 352x240.)

I'm using a ATI Radeon AIW 9800 capture/graphics card.

If you can't fix this problem, you can always capture at the higher resolution & then resize with VirtualDub or similar programme.

Something else also came to mind: Are you using a TBC when capturing from the VHS-C tape? VHS-C tape for me has been very unstable. I think it has something to do with the very small diameter video head and the head switching that goes on with this format.