XvShmCreateImage

XvCreateImage(3)                libXv Functions               XvCreateImage(3)



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).




X Version 11                     libXv 1.0.11                 XvCreateImage(3)