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反転機能を使用せずに画像を水平に反転する必要があります。正しいと思いましたが、返された画像は画像の右下隅にあり、反転されていません。

私が持っているコードは

def Flip(image1, image2):
    img = graphics.Image(graphics.Point(0, 0), image1)
    X = img.getWidth()
    Y = img.getHeight()
    for y in range(Y):
        for x in range(X):
            A = img.getPixel(x,y)
            r = A[0]
            g = A[1]
            b = A[2]
            color = graphics.color_rgb(r,g,b)
            img.setPixel(X-x,y,color)
    img = graphics.Image(graphics.Point(0,0), image2)
    win = graphics.GraphWin(image2, img.getWidth(), img.getHeight())
    img.draw(win)

どこで私は間違えましたか？

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1 に答える 1

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Here some things that I think could be improved:

def Flip(image1, image2):
    img = graphics.Image(graphics.Point(0, 0), image1)
    X = img.getWidth()
    Y = img.getHeight()
    for y in range(Y):
        for x in range(X):
            A = img.getPixel(x,y)
            r = A[0]
            g = A[1]
            b = A[2]
            color = graphics.color_rgb(r,g,b)

This assignment could be more pythonic:

            r, g, b = img.getPixel(x,y)
            color = graphics.color_rgb(r,g,b)

            img.setPixel(X-x,y,color)

img now has the image half-flipped. This happens because you are writing the content on the same image source, losing the old content anytime until you reach the middle. (Notice that X-x will increase the image size by 1 pixel. If the image width is 100, in the first iteration X-x = 100 - 0 = 100 and because it starts from 0, the image is made wider 1 pixel.) Then, you start copying back. Also, you do not use that content because:

    img = graphics.Image(graphics.Point(0,0), image2)

Here is the problem: you just overwrote the content of img without giving it any use. Later:

    win = graphics.GraphWin(image2, img.getWidth(), img.getHeight())
    img.draw(win)

This seems unrelated with the purpose of the function (flip an image). What I would do is:

import graphics
import sys

def Flip(image_filename):
    img_src = graphics.Image(graphics.Point(0, 0), image_filename)
    img_dst = img_src.clone()
    X, Y = img_src.getWidth(), img_src.getHeight()
    for x in range(X):
        for y in range(Y):
            r, g, b = img_src.getPixel(x, y)
            color = graphics.color_rgb(r, g, b)
            img_dst.setPixel(X-x-1, y, color)

    return img_dst

if __name__ == '__main__':
    input = sys.argv[1] or 'my_image.ppm'
    output = 'mirror-%s' % input
    img = Flip (input)
    img.save(output)

Notices that the function Flip only take care of flipping the image, outside the function you can do whatever you need the image, as you can see in 'main' program.

If you want to use only one image, it is possible and more efficient. For that, you can use the same principle for swapping values between variables:

def Flip(image_filename):
    img = graphics.Image(graphics.Point(0, 0), image_filename)
    X, Y = img.getWidth(), img.getHeight()
    for x in range(X/2):
        for y in range(Y):
            r_1, g_1, b_1 = img.getPixel(x, y)
            color_1 = graphics.color_rgb(r_1, g_1, b_1)

            r_2, g_2, b_2 = img.getPixel(X-x-1, y)
            color_2 = graphics.color_rgb(r_2, g_2, b_2)

            img.setPixel(X-x-1, y, color_1)
            img.setPixel(x, y, color_2)

    return img
于 2013-04-15T01:25:03.110 に答える