This function obtains the pixel at coordinates (nXpos, nYpos), storing it right justified (that is, in the least significant bits) at the location pointed to by lpPixel.
Declaration:
|
Copy Code
|
AT_ERRCOUNT ACCUAPI IG_DIB_pixel_get (
HIGEAR hIGear,
AT_PIXPOS nXpos,
AT_PIXPOS nYpos,
LPAT_PIXEL lpPixel
);
|
Arguments:
Name |
Type |
Description |
hIGear |
HIGEAR |
HIGEAR handle of image. |
nXpos |
AT_PIXPOS |
X offset (in pixels) from beginning of raster line. First pixel on line is pixel number 0. |
nYpos |
AT_PIXPOS |
Raster line number. 0 is top line. |
lpPixel |
LPAT_PIXEL |
Far pointer to byte at which to store pixel (or to a 3-byte area if a 24-bit pixel). |
Return Value:
Returns the number of ImageGear errors that occurred during this function call. If there are no errors, the return value is IGE_SUCCESS.
Supported Raster Image Formats:
All pixel formats supported by ImageGear for C and C++.
Sample:
Pixel Access, FlashPix
Example:
|
Copy Code
|
HIGEAR hIGear; /* HIGEAR handle of image */
AT_PIXEL cPixelValue[3];/* 3 bytes in case 24-bit image */
/* Get value of the upper-leftmost pixel in image: */
IG_DIB_pixel_get ( hIGear, 0, 0, &cPixelValue[0] );
|
Remarks:
If the pixel is 1-bit or 4-bit, the remaining bits of the byte will be set to zeroes.
If the pixel is 24-bit, 3 bytes are returned. These will be in the order Blue-Green-Red (unless you have changed the order of the image bitmap bytes such as by calling function IG_IP_swap_red_blue()).
ImageGear's pixel access functions consider the coordinates (0,0) to refer to the upper left-hand corner of the bitmap data. They do not follow the DIB's orientation, which considers (0,0) to refer to the lower left-hand corner of the bitmap.