xfree86 man page for xvquerybestsize

XvQueryBestSize(3X)													       XvQueryBestSize(3X)

Name
       XvQueryBestSize - determine the optimum drawable region size

Syntax
       #include <X11/extensions/Xvlib.h>

       XvQueryBestSize(dpy, port, motion, vw, vh, dw, dh, p_dw, p_dh)

       Display *dpy;
       XvPortID port;
       Bool motion;
       unsigned int vw, vh;
       unsigned int dw, dh;
       unsigned int *p_dw, *p_dh;

Arguments
       dpy	      Specifies  the  display  screen  on which the Xv Server is to accept requests from Xv clients.  If the display option is not
		      specified, Xv uses the display screen specified by your DISPLAY environment variable.  The display  option  has  the  format
		      hostname:number.	Using two colons (::) instead of one (:) indicates that DECnet is to be used for transport.

       port	      Defines the port associated with the display and adaptor for which the optimum size is to be calculated.

       motion	      Specifies  True  if  the	destination size needs to support full motion, and False if the destination size need only support
		      still images.

       vw,vh	      Specifies the size of the source video region desired.

       dw,dh	      Specifies the size of the destination drawable region desired.

       p_dw,p_dh      Pointers to where the closest destination sizes supported by the server are returned.

Description
       Some ports may be able to scale incoming or outgoing video.  XvQueryBestSize(3X) returns the size of the closest destination region that is
       supported by the adaptor.  The returned size is guaranteed to be smaller than the requested size if a smaller size is supported.

Returned Values
       [Success]
	       Returned if XvQueryBestSize(3X) completed successfully.

       [XvBadExtension]
	       Returned if the Xv extension is unavailable.

       [XvBadAlloc]
	       Returned if XvQueryBestSize(3X) failed to allocate memory to process the request.

Diagnostics
       [XvBadPort]
	       Generated if the requested port does not exist.

XFree86 							   Version 4.7.0					       XvQueryBestSize(3X)