v4l2, why need VIDIOC_DQBUF 2 times to get the latest frame
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Since May 18, 2017.
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Description
hello, I have a raspberry pi 2 mode b+
I want to take a still image from camera through v4l2 api,
This is my code http://paste.ubuntu.com/15099128/,
my question is why do I need ioctl VIDIOC_QBUF and VIDIOC_DQBUF 2 times to get the latest frame?
Thanks.
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