Analyzing pixel RGB values with PIL

Question

I'm working on a project where I need to find the RGB values of each pixel in a picture. How could I do this using PIL? I know that Pillow is better, but since I only need to do this one thing I thought I could just use PIL. If this won't work as well please tell me.

Answer 1

from PIL import Image
img = Image.open("filename.png")
pixels = img.load()

#get the B value of the pixel at x=23, y=42
print pixels[23, 42][2]

Answer 2

The previous answer is a good solution but just suggesting another way which is one line:

from scipy import misc;

imgData = misc.imread('./image.png');

You can then easily get the colors at every pixels you need.

Answer 3

Kevin got it pretty much spot on, you can also use getdata() to return a list of tuples.

I may have got this totally wrong, but load() might work better if you need particular pixels, and getdata() if you need all of them. Also, it's a good idea to convert to RGB if it's just a normal image, I've had errors before by not doing that.

image = Image.open('filename').convert('RGB')
width, height = image.size

#Get pixels in a list of tuples
pixels = image_input.getdata()

#If you need a flat list containing all the colours
bytes = [j for i in pixels for j in i]

If you needed to do stuff to the pixels and rebuild the image after, that's where the image size comes in useful.