RGB and grayscale conversion algorithms

What is a grayscale image? Any color is composed of three primary colors: red, green, and blue. If the color of a certain point is RGB (R, G, B), we can use the following methods, convert it to grayscale:

1. Floating point algorithm: Gray = R * 0.3 + G * 0.59 + B * 0.11

2. Integer method: Gray = (R * 30 + G * 59 + B * 11)/100

3. Shift method: Gray = (R * 76 + G * 151 + B * 28)> 8;

4. Average method: Gray = (R + G + B)/3;

5. Green only: Gray = G;

After obtaining the Gray using any of the above methods,

Replace R, G, and B in the original RGB (R, G, B) with Gray,

New colors: RGB (Gray, Gray, Gray ),

Replacing the original RGB (R, G, B) with it is a grayscale image.