XvPutStill(3X) writes a single frame of video to a drawable. The position and size of the source (video) rectangle is specified by
vx, vy, vw , and vh. The position and size of the destination (drawable) rectangle is specified by dx, dy, dw, and dh.Video data is clipped to the bounds of the video encoding, scaled to the requested drawable region size (or the closest size supported) and clipped to the bounds of the drawable.
If the port is grabbed by another client, this request is ignored, and an XvVideoNotify event with detail XvBusy is generated for the drawable. If the port is not receiving a valid video signal a VideoNotify event with detail XvHardError is generated for the drawable.