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 PillowTestCase, assert_image_equal


class TestImageTranspose(PillowTestCase):

    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(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(FLIP_LEFT_RIGHT)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size)

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

        for mode in self.hopper:
            transpose(mode)

    def test_flip_top_bottom(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(FLIP_TOP_BOTTOM)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size)

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

        for mode in self.hopper:
            transpose(mode)

    def test_rotate_90(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(ROTATE_90)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size[::-1])

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

        for mode in self.hopper:
            transpose(mode)

    def test_rotate_180(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(ROTATE_180)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size)

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

        for mode in self.hopper:
            transpose(mode)

    def test_rotate_270(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(ROTATE_270)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size[::-1])

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

        for mode in self.hopper:
            transpose(mode)

    def test_transpose(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(TRANSPOSE)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size[::-1])

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

        for mode in self.hopper:
            transpose(mode)

    def test_tranverse(self):
        def transpose(mode):
            im = self.hopper[mode]
            out = im.transpose(TRANSVERSE)
            self.assertEqual(out.mode, mode)
            self.assertEqual(out.size, im.size[::-1])

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

        for mode in self.hopper:
            transpose(mode)

    def test_roundtrip(self):
        for mode in self.hopper:
            im = self.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)
            )