[AG-TECH] Interlaced images produced by Bt848/Bt878 compliants

[shudo at ni.aist.go.jp]

Dear all,

We are in trouble with a video capture card.
It has a Conexant's Fusion 878A, which is very popular as
a Bt848/Bt878 compliant chip.

It is working well with our video computer in an AG node and we have
been satisfied by the quality of digital images produced by the card.
Recently, we are evaluating several video capturing devices for real
production uses and someone pointed out a critical and unacceptable
problem of the produced images.

Produced images look interlaced cleary.
In case that captured video is dynamic, even lines and odd lines of
a produced image show different frames of original video.
Generally, we see a pattern like a comb.

This problem is not due to VIC because we see the same comb-ed images
even using other capturing programs. I suppose the cause is in the
device driver or the capturing chip/card. We use Linux 2.4.X and the
standard device driver for Bt848. An USB camera I have tried does not
have this problem.


I have several questions:

Does anyone see this problem with Bt848 compliants?
Or with other PCI capture card?

Does anyone see this problem on Windows?

If you have this problem, are you accept this quality of images?


  Kazuyuki Shudo	shudo at computer.org	http://www.shudo.net/