How can I process images faster with Python?

Question

I'd trying to write a script that will detect an RGB value on the screen then click the x,y values. I know how to perform the click but I need to process the image a lot faster than my code below currently does. Is this possible with Python?

So far I'm reading a row at a time, when x = 1920 I go onto the second row but it takes about 10 seconds to do one row. By that time the person on screen would have moved into a completely different spot and I have only done one row!

Can I speed this code up OR is there a better way to achieve what I want? If it is not possible in Python I am open to C++ options :)

import Image

x = 0
y = 0

im = Image.open("C:\Users\sean\Desktop\screen.jpg")
pix = im.load()
print im.size #get width and height of the image for iterating over
while x < 1920:
    print pix[x,y] #get RGBA value of the pixel of an image
    print "x is:" +str(x)
    x = x + 1
    print "y is: " +str(y)
    if x == 1920:
        x = 0
        y = y + 1

Answer 1

Generally, you want to avoid per-pixel loops in Python. They will always be slow. To get somewhat fast image processing, you need to get used to working with matrices instead of individual pixels. You have basically two options, you can either use NumPy or OpenCV, or a combination of the two. NumPy is a generic mathemtical matrix/array library, but you can do many image-related things with it. If you need something more specific, OpenCV supports many common operations on images.

Answer 2

Thanks for the responses, below is the code I used, I didn't change my original. Turns out it is fast enough but printing is a very costly operation :) It finds the x and y coords of the RGB value in less than a second

#check for certain RGB in image

##need to screen grab

import Image, sys

x = 0
y = 0

im = Image.open('C:\\Users\\sean\\Desktop\\test.jpg')
pix = im.load()
print im.size #get width and height of the image for iterating over
while x < 1914:
    value = pix[x,y] #get RGBA value of the pixel of an image
    if value == (33, 179, 80):
        #call left_click(x,y)
        print x,y
    x = x + 1
    if x == 1914:
        x = 0
        y = y + 1
print "Finished"
sys.exit()