Get pixel's RGB using PIL
PythonImagePython Imaging-LibraryRgbPixelPython Problem Overview
Is it possible to get the RGB color of a pixel using PIL? I'm using this code:
im = Image.open("image.gif")
pix = im.load()
print(pix[1,1])
However, it only outputs a number (e.g. 0
or 1
) and not three numbers (e.g. 60,60,60
for R,G,B). I guess I'm not understanding something about the function. I'd love some explanation.
Thanks a lot.
Python Solutions
Solution 1 - Python
Yes, this way:
im = Image.open('image.gif')
rgb_im = im.convert('RGB')
r, g, b = rgb_im.getpixel((1, 1))
print(r, g, b)
(65, 100, 137)
The reason you were getting a single value before with pix[1, 1]
is because GIF pixels refer to one of the 256 values in the GIF color palette.
See also this SO post: https://stackoverflow.com/questions/5800009/python-and-pil-pixel-values-different-for-gif-and-jpeg and this PIL Reference page contains more information on the convert()
function.
By the way, your code would work just fine for .jpg
images.
Solution 2 - Python
GIFs store colors as one of x number of possible colors in a palette. Read about the gif limited color palette. So PIL is giving you the palette index, rather than the color information of that palette color.
Edit: Removed link to a blog post solution that had a typo. Other answers do the same thing without the typo.
Solution 3 - Python
With numpy :
im = Image.open('image.gif')
im_matrix = np.array(im)
print(im_matrix[0][0])
Give RGB vector of the pixel in position (0,0)
Solution 4 - Python
An alternative to converting the image is to create an RGB index from the palette.
from PIL import Image
def chunk(seq, size, groupByList=True):
"""Returns list of lists/tuples broken up by size input"""
func = tuple
if groupByList:
func = list
return [func(seq[i:i + size]) for i in range(0, len(seq), size)]
def getPaletteInRgb(img):
"""
Returns list of RGB tuples found in the image palette
:type img: Image.Image
:rtype: list[tuple]
"""
assert img.mode == 'P', "image should be palette mode"
pal = img.getpalette()
colors = chunk(pal, 3, False)
return colors
# Usage
im = Image.open("image.gif")
pal = getPalletteInRgb(im)
Solution 5 - Python
Not PIL, but imageio.imread
might still be interesting:
import imageio
im = scipy.misc.imread('um_000000.png', flatten=False, mode='RGB')
im = imageio.imread('Figure_1.png', pilmode='RGB')
print(im.shape)
gives
(480, 640, 3)
so it is (height, width, channels). So the pixel at position (x, y)
is
color = tuple(im[y][x])
r, g, b = color
Outdated
scipy.misc.imread
is deprecated in SciPy 1.0.0 (thanks for the reminder, fbahr!)