VPrepareColorImage
Name
VPrepareColorImage - computes a prepared image to be displayed with
truecolor on.
Synopsis
VPrepareColorImage(data, width, height, bits_per_rgb, min, max, ximage)
unsigned char *data;
int width, height;
int bits_per_rgb;
unsigned long min, max;
XImage *ximage; /*RETURN*/
Description
VPrepareColorImage computes a prepared image to be displayed with
truecolor on. The input data format is RGB, RGB, ...., RGB. If bits_per_rgb
is 8, the input data is assigned to character pointer type. If
bits_per_rgb is 16, the input data is assigned to short pointer type. The
output data byte order depends on the X server, and VPrepareColorImage
gets this information from XImageByteOrder. In order to display the prepared
image stored in ximage, VPutImage should be called. The data stored by
the ximage structure (ximage->data) can be freed by calling free().
Return Value
0 - work successfully.
1 - memory allocation error.
Parameters
data - specifies an array of data to be computed.
width,height - specifies the width and height in pixels of the image.
bits_per_rgb - specifies the number of bits of each RGB component, the
value is 8 or 16.
min, max - the minimum and maximum gray values of the image data.
ximage - returns precomputed image into the XImage structure.
Side Effects
None.
Entry Conditions
If the value of width, height, or bits_per_rgb is not valid, or
VCreateColormap is not called earlier, VPrepareColorImage prints an error
message to the standard error stream, produces a core dump file and exits
from the current process.
Related Functions
VPrepareGrayImage,
VDisplayGrayImage,
VDisplayColorImage,
VPutImage,
VGetImage,
VTurnOnTruecolor,
VTurnOffTruecolor.