Video Capture Sequence of V4L2 IOCTL Calls
Optional IOCTL
1. VIDIOC_QUERYCAP | struct v4l2_capability
2. VIDIOC_CROPCAP | struct v4l2_cropcap
3. VIDIOC_ENUM_FMT | struct v4l2_fmtdesc
Necessary IOCTL
Initialize Video Device
1. VIDEOIC_S_FMT | struct v4l2_format
2. VIDEOIC_G_FMT | struct v4l2_format
Memory Mapping/Buffering
3. VIDEOIC_REQBUFS | struct v4l2_requestbuffers
4. VIDEOIC_QUERYBUF | struct v4l2_buffer
Start Capturing
5. VIDEOIC_QBUF | struct v4l2_buffer
6. VIDEOIC_STREAMON | struct v4l2_buffer
Exchanging Buffer
7. VIDEOIC_DQBUF
8. VIDEOIC_QBUF
Stop Capturing
9. VIDEOIC_STREAMOFF
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