I don't understand the point of the VIDIOCCAPTURE ioctl. I expected
that I would have to call it before doing a read(). But there is no
need, after VIDIOCSWIN the read works anyway.
According to the v4lapi:
Merely setting the window does not enable capturing. Overlay
capturing is activatied by passing the VIDIOCCAPTURE ioctl a
value of 1, and disabled by passing it a value of 0.
So what is the function of this ioctl?
Gerd Knorr wrote:
Jeffrey Dever <jsdever@xxxxxxxxxxxx> writes:
I'm perplexed as to how to read captures from the video device. I can
do quite a bit to control my webcam (probe, set window ...) but there
seems to be several modes of reading captures. I'm just trying to do
a simple capture, so I don't want to use mmap at this point as I want
to keep it as simple as possible.
If you are using bttv, make sure you have the 0.9.x version. In 0.7.x
capture via read() simply doesn't work.
Gerd
