In This Topic ▼

LBitmapBase::PutPixelColor

Summary

Changes the color value of the specified pixel in the class object's bitmap.

Syntax

#include "ltwrappr.h"

virtual L_INT LBitmapBase::PutPixelColor(nRow, nCol, crColor)

Parameters

L_INT nRow

The row number of the pixel. This is a zero-based value.

L_INT nCol

The column number of the pixel. This is a zero-based value.

The color to assign to the pixel. The standard Windows values for COLORREF represent either red, green, and blue color values, or an index into the bitmap's palette. A COLORREF value with the format 0x00BBGGRR represents the blue, green, and red color values for the specified pixel, where 0xBB is the blue value, 0xGG is the green value and 0xRR is the red value. If 0x01000000 is set in the COLORREF value (0x010000ZZ), the lower 8 bits (0xZZ) represent an index into the bitmap's palette which holds the color value. These COLORREF values can be used with any Windows function and macro that takes a COLORREF parameter.

In the Document/Medical toolkits, the COLORREF value may represent a 16 bit grayscale value if pBitmap is a 12 or 16-bit grayscale bitmap, or a 32-bit grayscale value if pBitmap is a 32-bit grayscale bitmap. So that the value is not confused with an RGB value, the COLORREF_GRAY16 mask (0x04000000) is set. In this case (0x0400YYYY), the lower 16 bits (0xYYYY) of the COLORREF value represent the 16-bit grayscale value. (0x0400FFFF is 16-bit white and 0x04000000is 16-bit black.) This is not a standard Windows value. Therefore, LEADTOOLS functions will recognize a COLORREF having this format, but Windows functions will not. For information on how to use a 16-bit grayscale COLORREF in a non-LEADTOOLS function, refer to LBitmapBase::GetPixelColor. If pBitmap is a 32-bit grayscale bitmap, crColor is treated as a 32-bit grayscale value.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function uses bitmap coordinates to specify the pixel. Therefore, you must account for the view perspective of the bitmap. For more information, refer to Accounting for View Perspective.

This function always uses TOP_LEFT ViewPerspective coordinates to specify the pixel. Therefore, you do not have to account for the view perspective of the bitmap. For more information, refer to Accounting for View Perspective.

If you specify a pixel that is outside the bitmap or outside the region (if the bitmap has one), this function returns an error.