XvSetPortAttribute - sets an attribute of a video port
#include <X11/extensions/Xvlib.h>
int XvSetPortAttribute(Display *dpy, XvPortID port,
                       Atom attribute, int value);
  - dpy
- Specifies the connection to the X server.
- port
- Specifies the port for which the attribute is to be used.
- attribute
- Identifies the port attribute to be set by this request. Can be one of the
      table entries under the column "String," below.
- value
- Identifies the value to which attribute is to be set. Can be one of
      the table entries under the column "Type," below.
XvSetPortAttribute(3)
 permits a client to set the port attribute to specified values. This request
  supports the following values:
  
  
  
    | Attribute String | Type | Default | 
  
    | "XV_ENCODING" | XvEncodingID | Server dependent | 
  
    | "XV_HUE" | [-1000...1000] | 0 | 
  
    | "XV_SATURATION" | [-1000...1000] | 0 | 
  
    | "XV_BRIGHTNESS" | [-1000...1000] | 0 | 
  
    | "XV_CONTRAST" | [-1000...1000] | 0 | 
The supplied encoding must be one of the encodings listed for the
    adaptor, otherwise an Encoding error results.
If the adaptor does not support the exact hue, saturation,
    brightness, and contrast levels supplied, the closest levels supported are
    assumed. Use XvGetPortAttribute(3) to query the resulting levels.
When an XvSetPortAttribute(3) request is processed, a
    XvPortNotify(3) event is generated for all clients that have
    requested notification of port changes using
  XvSelectPortNotify(3).
  - [Success]
- Returned if XvSetPortAttribute(3) completed successfully.
- [XvBadExtension]
- Returned if the Xv extension is unavailable.
- [XvBadAlloc]
- Returned if XvSelectVideoNotify(3) failed to allocate memory to
      process the request.
  - [XvBadPort]
- Generated if the requested port does not exist.
- [XvBadEncoding]
- Generated if an encoding is specified that does not exist.
- [BadMatch]
- Generated if the requested attribute atom does not specify an attribute
      supported by the adaptor.
XvGetPortAttribute(3), XvQueryPortAttributes(3),
  XvSelectPortNotify(3), XvPortNotify(3)