How to Convert an Image to Gray Scale With WPF
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Join For FreeThe easiest way to convert an image to gray scale is to set the RGB values of every pixel to the average of each pixels RBG values.
R = (R + B + G) / 3
G = (R + B + G) / 3
B = (R + B + G) / 3
Here's a code snippet for manipulating a BitmapSource object using the WriteableBitmap class into a gray scale image:
public unsafe static BitmapSource ToGrayScale(BitmapSource source) { const int PIXEL_SIZE = 4; int width = source.PixelWidth; int height = source.PixelHeight; var bitmap = new WriteableBitmap(source); bitmap.Lock(); var backBuffer = (byte*)bitmap.BackBuffer.ToPointer(); for (int y = 0; y < height; y++) { var row = backBuffer + (y * bitmap.BackBufferStride); for (int x = 0; x < width; x++) { var grayScale = (byte)(((row[x * PIXEL_SIZE + 1]) + (row[x * PIXEL_SIZE + 2]) + (row[x * PIXEL_SIZE + 3])) / 3); for (int i = 0; i < PIXEL_SIZE; i++) row[x * PIXEL_SIZE + i] = grayScale; } } bitmap.AddDirtyRect(new Int32Rect(0, 0, width, height)); bitmap.Unlock(); return bitmap; }
Another way to to convert an image to gray scale is to set the RGB values of every pixel to the sum of 30% of the red value, 59% of the green value, and 11% of the blue value. Hope you find this useful.
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