bright - adjust brightness of an image Calling Sequence: img = bright(im,rate) Parmeters: im: this is a MxNx3 unsigned char matrix(uint8). rate: a value between -100 and 100,it shows the degree of brightness img: a MxNx3 unsigned char matrix of output image Description: This function adjust brightness of an input image.If "rate" equals to 0,we'll not change the image's brightness.if rate<0,we get an image darker than input.The more ratio,the more brightness. Example: im = imread("lena.png"); img = brightness(im,25);