NAME

       XvQueryAdaptors - return adaptor information for a screen

SYNOPSIS

       #include <X11/extensions/Xvlib.h>

       int XvQueryAdaptors(Display *dpy, Window window,
                           unsigned int *p_num_adaptors,
                           XvAdaptorInfo **pp_adaptor_info);

ARGUMENTS

       dpy     Specifies the connection to the X server.

       window  Specifies a window of the screen for which the adaptor information is desired.

       p_num_adaptors
               A pointer to where the number of adaptors for the specified screen is returned.

       pp_adaptor_info
               A pointer to where the list of returned adaptor information is returned.

DESCRIPTION

       XvQueryAdaptors(3)
        returns  an  video  adaptor  information  for  the screen of the specified drawable.  The
       XvAdaptorInfo structure has the following organization:

            typedef struct {
              XvPortID base_id;
              unsigned long num_ports;
              char type;
              char *name;
              unsigned long num_formats;
              XvFormat *formats;
              unsigned long num_adaptors;
            } XvAdaptorInfo;

       base_id The resource ID of the first adaptor port.

       num_ports
               The number of ports supported by the adaptor.

       type    A bit mask with the value XvInputMask  asserted  if  the  adaptor  supports  video
               input,  and  value XvOutputMask asserted if the adaptor supports video output.  In
               Xv protocol 2.2 and later, there are 3 new bits defined - XvVideoMask, XvStillMask
               and  XvImageMask  indicating  that the adaptor is capable of video, still or image
               primitives respectively.

       name    A vendor specific name that identifies the adaptor.

       num_formats
               The number of depth/visual id formats supported by the adaptor.

       formats A pointer to an array of XvFormat structures.

       The XvFormat structure has the following organization:

            typedef struct {
              char depth;
              unsigned long visual_id;
            } XvFormat;

       depth   A drawable depth supported by the adaptor.

       visual_id
               A visual-id supported for the given depth by the adaptor.

RETURN VALUES

       [Success]
               Returned if XvQueryAdaptors(3) completed successfully.

       [XvBadExtension]
               Returned if the Xv extension is unavailable.

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

DIAGNOSTICS

       [Drawable]
               Returned if the requested drawable does not exist.

SEE ALSO

       XvFreeAdaptorInfo(3)