Hi all,
I've tried to do some threading magic in lavrec... Basically, sync
(VIDIOCSYNC) and queue (VIDIOCMCAPTURE) calls go in different threads.
Problem: I queue all buffers, then sync on each of them, give the buffer
to a different thread and let it re-queue it. After some time (testing,
100% CPU load, so I can't keep up and have to lose frames...), when my
number of queued buffers starts to decrease to zero and I'm about to
sync on yet-unqueued buffers, I get a -EINV return value ("invalid
argument") on my next VIDIOCSYNC.
How threadsafe is v4l supposed to be? Can I sync on unqueued buffers
(assuming, of course, that they'll be queued later on - i.e. I'm losing
frames)? Does anyone have a clue on what might be going wrong?
The kernel log doesn't tell me anything useful... The card is a winTV
(Bt848 chip) from Hauppauge. The only modprobe argument I'm using is
"gbuffers=32".
Ronald
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