After some experimenting I found out that the problem occurs only (?) if you try to read n%3 == 1 frames between opening and closing the /dev/video32 device.
[WORKAROUND] So a workaround that -seems- to work for me is the following: after opening /dev/video32, always read a full multiple of three frames (or 3x+2, but never 3x+1) before closing the device again. [/WORKAROUND] Unfortunately, I was not able to find a reasonable answer to the question for which 3x+1 this problem is reproducible. For x=33, (reading 100 frames), it happens most of the time, yet for x=39, (reading 118 frames), it happens sometimes... Hans, I'm in PAL-country. By the way: the problem seems to be present not only in frames 6,24,42,60, ... (the known problem with the top 1/3 of the frame), but also in frames 12,30,48,68, ... (the first 8(?) lines of the frame for approx. 2/3 of the width). _Ramon On 1/4/07, Ramon (IVTV) <[EMAIL PROTECTED]> wrote:
Hi all, Thanks very much for the fabulous work on this driver. I've a problem with YUV capture (via /dev/video32). On capture the top part of the frame is missing from every 18th frame. This top part is very dark and it contains some grey diagonal block pattern. This happens from the second time I open /dev/video32. Hence, in the past (ivtv 0.4.x) I used to reset the firmware (ivtvctl -H) before capturing. Yet, this work-around is not possible anymore with ivtv 0.8.x (the firmware-reset ioctl doesn't exist anymore?). Unfortunately, I do not have the experience to dive into the code of the driver and find out what is happening... Can someone please help me (with a work-around)? Regards, _Ramon Clout
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