How to open Blender's image using Pillow?

Question

I'm using PIL to an addon I'm working on and at some point I need to open images using pillow. The usual way to do is

from PIL import Image
Image.open('whatever your image is')

But with images created within Blender, the only access is using bpy.data.image['the image'] which causes error using Image.open from PIL.

I get the following error when I type: Image.open(bpy.data.image['test'])

Traceback (most recent call last):
  File "C:\Users\myName\AppData\Roaming\Python\Python39\site-packages\PIL\Image.py", line 3096, in open
    fp.seek(0)
AttributeError: 'Image' object has no attribute 'seek'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<blender_console>", line 1, in <module>
  File "C:\Users\myName\AppData\Roaming\Python\Python39\site-packages\PIL\Image.py", line 3098, in open
    fp = io.BytesIO(fp.read())
AttributeError: 'Image' object has no attribute 'read'

I found some idea using pixels and Image.fromarray but nothing conclusive so far...

How do you load Blender's image like bpy.data.image['the image'] into PIL image?

Answer 1

The method Image.open is only used to open file paths. But you can simply transform the pixels into bytes and use Image.frombytes instead to get the pillow image:

import bpy
from PIL import Image
import io
import struct

img = bpy.data.images['test']

pixels = [int(px * 255) for px in img.pixels[:]]
bytes = struct.pack("%sB" % len(pixels), *pixels)

image = Image.frombytes('RGBA', (img.size[0], img.size[1]), bytes)
image = image.transpose(Image.FLIP_LEFT_RIGHT).rotate(180)

image.show()

For those who have not installed the PIL module. You can install it with the following script using pip.

import subprocess
import sys
import os
 
python_exe = os.path.join(sys.prefix, 'bin', 'python.exe')

subprocess.call([python_exe, '-m', 'ensurepip'])
subprocess.call([python_exe, '-m', 'pip', 'install', '--upgrade', 'pip'])
subprocess.call([python_exe, '-m', 'pip', 'install', '--upgrade', 'pillow'])

You can read more about installing python modules here. Note that the original Python Imaging Library (PIL) was the popular image processing library for Python. However, development on PIL ceased a long time ago, and the project was dormant for several years. As a result, the community created a fork of PIL called Pillow to continue its development and maintenance.

Answer 2

Based on great answer of Harry McKenzie just for convenience for the next guy looking for this:

import bpy
import os
import subprocess
import sys
import io
import struct
import numpy as np

try:
    from PIL import Image
except: 
    python_exe = os.path.join(sys.prefix, 'bin', 'python.exe')
    subprocess.call([python_exe, '-m', 'ensurepip'])
    subprocess.call([python_exe, '-m', 'pip', 'install', '--upgrade', 'pip'])
    subprocess.call([python_exe, '-m', 'pip', 'install', '--upgrade', 'pillow'])
    
def pil_to_image(pil_image, name='NewImage'):
    width, height = pil_image.width, pil_image.height
    normalized = 1.0 / 255.0
    bpy_image = bpy.data.images.new(name, width=width, height=height)
    bpy_image.pixels[:] = (np.asarray(pil_image.convert('RGBA'),dtype=np.float32) * normalized).ravel()
    return bpy_image

def image_to_pil(bpy_image):
    img = bpy_image
    pixels = [int(px * 255) for px in bpy_image.pixels[:]]
    bytes = struct.pack("%sB" % len(pixels), *pixels)
    pil_image = Image.frombytes('RGBA', (bpy_image.size[0], bpy_image.size[1]), bytes)
    return pil_image


im = image_to_pil(bpy.data.images["test"])
im = im.transpose(Image.FLIP_LEFT_RIGHT).rotate(45)
pil_to_image(im)