ioctl VIDIOC_SUBDEV_G_SELECTION, VIDIOC_SUBDEV_S_SELECTION &manvol; VIDIOC_SUBDEV_G_SELECTION VIDIOC_SUBDEV_S_SELECTION Get or set selection rectangles on a subdev pad int ioctl int fd int request struct v4l2_subdev_selection *argp Arguments fd &fd; request VIDIOC_SUBDEV_G_SELECTION, VIDIOC_SUBDEV_S_SELECTION argp Description Experimental This is an experimental interface and may change in the future. The selections are used to configure various image processing functionality performed by the subdevs which affect the image size. This currently includes cropping, scaling and composition. The selection API replaces the old subdev crop API. All the function of the crop API, and more, are supported by the selections API. See for more information on how each selection target affects the image processing pipeline inside the subdevice.
Types of selection targets There are two types of selection targets: actual and bounds. The actual targets are the targets which configure the hardware. The BOUNDS target will return a rectangle that contain all possible actual rectangles.
Discovering supported features To discover which targets are supported, the user can perform VIDIOC_SUBDEV_G_SELECTION on them. Any unsupported target will return EINVAL.
Selection targets and flags are documented in . struct <structname>v4l2_subdev_selection</structname> &cs-str; __u32 which Active or try selection, from &v4l2-subdev-format-whence;. __u32 pad Pad number as reported by the media framework. __u32 target Target selection rectangle. See . __u32 flags Flags. See . &v4l2-rect; rect Selection rectangle, in pixels. __u32 reserved[8] Reserved for future extensions. Applications and drivers must set the array to zero.
&return-value; EBUSY The selection rectangle can't be changed because the pad is currently busy. This can be caused, for instance, by an active video stream on the pad. The ioctl must not be retried without performing another action to fix the problem first. Only returned by VIDIOC_SUBDEV_S_SELECTION EINVAL The &v4l2-subdev-selection; pad references a non-existing pad, the which field references a non-existing format, or the selection target is not supported on the given subdev pad.