NAME

       XvCreateImage, XvShmCreateImage - create an XvImage

SYNOPSIS

       #include <X11/extensions/Xvlib.h>

       XvImage * XvCreateImage (Display *dpy, XvPortID port,
                                int id, char *data,
                                int width, int height);

       XvImage * XvShmCreateImage (Display *dpy, XvPortID port,
                                   int id, char *data,
                                   int width, int height,
                                   XShmSegmentInfo *shminfo);

ARGUMENTS

       dpy     Specifies the connection to the X server.

       port    Specifies the port the XvImage will be used with.

       id      Specifies the format of the image to be created by the XvImageFormatValues id.

       data    Specifies the image data.

       width, height
               Specifies the desired width and height of the image.

DESCRIPTION

       XvCreateImage(3)  is  similar  to  XCreateImage(3).   XvShmCreateImage(3)  is  similar  to
       XShmCreateImage(3).  The library will allocate the XvImage  structure  and  fill  out  all
       fields  except  for data.  Width and height may be enlarged in some YUV formats.  The size
       of the data buffer that needs to be allocated will be given in the data_size field in  the
       XvImage.   Image data is not allocated by this function.  The client may pass a pointer to
       the preallocated memory as data or may  allocate  the  memory  and  fill  in  the  XvImage
       structure's  data  field after the data_size field has been filled out by the server.  The
       XvImage structure may be freed by XFree(3).  Shared memory segments are  attached/detached
       with XShmAttach(3)/XShmDetach(3).

RETURN VALUES

       XvImage has the following structure:

       typedef struct {
          int id;
          int width, height;
          int data_size;
          int num_planes;
          int *pitches;
          int *offsets;
          char *data;
          XPointer obdata;
       } XvImage;

       id      A  descriptor  for  the  format from the XvImageFormatValues structure returned by
               XvListImageFormats(3).

       width, height
               The width and height of the image in pixels.

       data_size
               The size of the data buffer in bytes.

       num_planes
               The number of image planes.

       pitches An array of size num_planes indicating the scanline pitch in  bytes.   Each  plane
               may have a different pitch.

       offsets An  array  of size num_planes indicating the byte offset from data to the start of
               each plane.

       data    A pointer to the start of the data buffer.

       obdata  A private field for holding SHM info.  This field will be set  up  by  the  client
               libraries so the programmer will generally need not be concerned with this field.

DIAGNOSTICS

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

       [XvBadAlloc]
               Generated  if  the  X server was unable to allocate resources required to complete
               the operation.

       [BadMatch]
               Generated if incompatible arguments were supplied,  such  as  a  port  that  isn't
               capable of displaying XvImages.

SEE ALSO

       XvListImageFormats(3), XCreateImage(3), XShmCreateImage(3), XShmAttach(3), XShmDetach(3).