1.21. Detect Control Reference

The Detect class includes controls for common features of various motion or object detection capable devices.

1.21.1. Detect Control IDs

V4L2_CID_DETECT_CLASS (class)

The Detect class descriptor. Calling ioctls VIDIOC_QUERYCTRL, VIDIOC_QUERY_EXT_CTRL and VIDIOC_QUERYMENU for this control will return a description of this control class.

V4L2_CID_DETECT_MD_MODE (menu)

Sets the motion detection mode.

V4L2_DETECT_MD_MODE_DISABLED	Disable motion detection.
V4L2_DETECT_MD_MODE_GLOBAL	Use a single motion detection threshold.
V4L2_DETECT_MD_MODE_THRESHOLD_GRID	The image is divided into a grid, each cell with its own motion detection threshold. These thresholds are set through the V4L2_CID_DETECT_MD_THRESHOLD_GRID matrix control.
V4L2_DETECT_MD_MODE_REGION_GRID	The image is divided into a grid, each cell with its own region value that specifies which per-region motion detection thresholds should be used. Each region has its own thresholds. How these per-region thresholds are set up is driver-specific. The region values for the grid are set through the V4L2_CID_DETECT_MD_REGION_GRID matrix control.

V4L2_CID_DETECT_MD_GLOBAL_THRESHOLD (integer)

Sets the global motion detection threshold to be used with the V4L2_DETECT_MD_MODE_GLOBAL motion detection mode.

V4L2_CID_DETECT_MD_THRESHOLD_GRID (__u16 matrix)

Sets the motion detection thresholds for each cell in the grid. To be used with the V4L2_DETECT_MD_MODE_THRESHOLD_GRID motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the grid.

V4L2_CID_DETECT_MD_REGION_GRID (__u8 matrix)

Sets the motion detection region value for each cell in the grid. To be used with the V4L2_DETECT_MD_MODE_REGION_GRID motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the grid.