Pillow/Tests/test_image_transpose.py

from PIL.Image import (
    FLIP_LEFT_RIGHT,
    FLIP_TOP_BOTTOM,
    ROTATE_90,
    ROTATE_180,
    ROTATE_270,
    TRANSPOSE,
    TRANSVERSE,
)

from . import helper
from .helper import assert_image_equal

HOPPER = {
    mode: helper.hopper(mode).crop((0, 0, 121, 127)).copy()
    for mode in ["L", "RGB", "I;16", "I;16L", "I;16B"]
}


def test_flip_left_right():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(FLIP_LEFT_RIGHT)
        assert out.mode == mode
        assert out.size == im.size

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((x - 2, 1))
        assert im.getpixel((x - 2, 1)) == out.getpixel((1, 1))
        assert im.getpixel((1, y - 2)) == out.getpixel((x - 2, y - 2))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((1, y - 2))

    for mode in HOPPER:
        transpose(mode)


def test_flip_top_bottom():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(FLIP_TOP_BOTTOM)
        assert out.mode == mode
        assert out.size == im.size

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((1, y - 2))
        assert im.getpixel((x - 2, 1)) == out.getpixel((x - 2, y - 2))
        assert im.getpixel((1, y - 2)) == out.getpixel((1, 1))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((x - 2, 1))

    for mode in HOPPER:
        transpose(mode)


def test_rotate_90():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(ROTATE_90)
        assert out.mode == mode
        assert out.size == im.size[::-1]

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((1, x - 2))
        assert im.getpixel((x - 2, 1)) == out.getpixel((1, 1))
        assert im.getpixel((1, y - 2)) == out.getpixel((y - 2, x - 2))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((y - 2, 1))

    for mode in HOPPER:
        transpose(mode)


def test_rotate_180():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(ROTATE_180)
        assert out.mode == mode
        assert out.size == im.size

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((x - 2, y - 2))
        assert im.getpixel((x - 2, 1)) == out.getpixel((1, y - 2))
        assert im.getpixel((1, y - 2)) == out.getpixel((x - 2, 1))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((1, 1))

    for mode in HOPPER:
        transpose(mode)


def test_rotate_270():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(ROTATE_270)
        assert out.mode == mode
        assert out.size == im.size[::-1]

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((y - 2, 1))
        assert im.getpixel((x - 2, 1)) == out.getpixel((y - 2, x - 2))
        assert im.getpixel((1, y - 2)) == out.getpixel((1, 1))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((1, x - 2))

    for mode in HOPPER:
        transpose(mode)


def test_transpose():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(TRANSPOSE)
        assert out.mode == mode
        assert out.size == im.size[::-1]

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((1, 1))
        assert im.getpixel((x - 2, 1)) == out.getpixel((1, x - 2))
        assert im.getpixel((1, y - 2)) == out.getpixel((y - 2, 1))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((y - 2, x - 2))

    for mode in HOPPER:
        transpose(mode)


def test_tranverse():
    def transpose(mode):
        im = HOPPER[mode]
        out = im.transpose(TRANSVERSE)
        assert out.mode == mode
        assert out.size == im.size[::-1]

        x, y = im.size
        assert im.getpixel((1, 1)) == out.getpixel((y - 2, x - 2))
        assert im.getpixel((x - 2, 1)) == out.getpixel((y - 2, 1))
        assert im.getpixel((1, y - 2)) == out.getpixel((1, x - 2))
        assert im.getpixel((x - 2, y - 2)) == out.getpixel((1, 1))

    for mode in HOPPER:
        transpose(mode)


def test_roundtrip():
    for mode in HOPPER:
        im = HOPPER[mode]

        def transpose(first, second):
            return im.transpose(first).transpose(second)

        assert_image_equal(im, transpose(FLIP_LEFT_RIGHT, FLIP_LEFT_RIGHT))
        assert_image_equal(im, transpose(FLIP_TOP_BOTTOM, FLIP_TOP_BOTTOM))
        assert_image_equal(im, transpose(ROTATE_90, ROTATE_270))
        assert_image_equal(im, transpose(ROTATE_180, ROTATE_180))
        assert_image_equal(
            im.transpose(TRANSPOSE), transpose(ROTATE_90, FLIP_TOP_BOTTOM)
        )
        assert_image_equal(
            im.transpose(TRANSPOSE), transpose(ROTATE_270, FLIP_LEFT_RIGHT)
        )
        assert_image_equal(
            im.transpose(TRANSVERSE), transpose(ROTATE_90, FLIP_LEFT_RIGHT)
        )
        assert_image_equal(
            im.transpose(TRANSVERSE), transpose(ROTATE_270, FLIP_TOP_BOTTOM)
        )
        assert_image_equal(im.transpose(TRANSVERSE), transpose(ROTATE_180, TRANSPOSE))