dev-notes/python/libs/image/pillow.md

Pillow

Standard Imports

from PIL import Image

OPENING IMAGE FILE

Returns IOError if file cannot be opened.

image = Image.open(filepath, mode)    # open image file (returns Image object)
# FILEPATH: filename (string) or file object (musk implement seek, tell, write methods)

image.format    # image file extension
image.size    # 2-tuple (width, height) in pixels
image.mode    # defines number and name of bands in image, pixel type and depth

SAVING IMAGE FILE

image.save(filepath, fmt)
# FMT: optional format override

IMAGE CROPPING

box = (left, top, right, bottom)    # position in pixels
cropped = image.crop(box)

IMAGE PASTE

# region dimension MUST be same as box
image.paste(region, box)

SPLITTING AND MERGING BANDS

image.mode should be RGB

r, g, b = image.split()
img = image.merge(r, g, b)