Get access to bitmap image

hi someone know how can get access to the bitmap of an image?. i need to call or get the specific position of a pixel in an image to modify the value about his colour like a editor image bitmap. its possible that?.

Put your image to the background of a canvas, then you can select/get the pixel at any point (x/y)

is there some form to assign a variable of a pixel position in the bitmap image? like a global o local variable or using in a list?


I have been opaque, provide a clearer explanation of what you want to do.

i am trying to transform a region x and y of bitmap color in other colors using a mathematical formula. so i need to search all the pixels positions of an specific region in the image for make that

This may take quite a long time......

for each pixel in canvas background
   if pixel colour (RGB) == designated pixel colour (RGB) then
   do transformation()

ok thanks...