used for PPM image

1.3.3 Change a color image to Black & White (W) Color image (b) Black and white image Figure 1: A color image and its black and white counterpart. A black and white image is the one that the intensity values are the same for all color channels, red, green, and blue, at each pixel. To change a color image to grey, assign a new intensity, which is given by (R+G+B)/3, to all the color channels at a pixel. The R, G, B are the old intensity values for the red, the green, and the blue channels at the pixel. You need to define and implement the following function to do the job. /* change color image to black and white +/ void Blacknwhite (unsigned char RWIDTH] [HEIGHT), unsigned char G[WIDTH) (HEIGHT), unsigned char B[WIDTH] [HEIGHT]); 1.3.4 Make a negative of an image A negative image is an image in which all the intensity values have been inverted. To achieve this each intensity value at a pixel is subtracted from the maximum value, 255, and the result is assigned to the pixel as a new intensity. You need to define and implement a function to do the job. You need to define and implement the following function to do this DIP. /* reverse image color */ void Negative (unsigned char R[WIDTH] (HEIGHT), unsigned char G[WIDTH] [HEIGHT), unsigned char B [WIDTH] [HEIGHT]); (a) Original image (b) Negative image /*** global definitions ***/ const int WIDTH = 512; const int HEIGHT = 288; const int SLEN 80; /* image width */ /* image height */ /* max. string length */