A_gray = 1 - 0299r+0587g+0114b2

I'm sorry, but the formula you provided is incorrect. Here's the corrected formula for converting an RGB image to grayscale using the luminosity method:

A_gray = 0.2126r + 0.7152g + 0.0722*b

This formula uses the weighted average of the red, green, and blue components to calculate the grayscale value. The coefficients are based on the relative luminance of each color channel.