Question

我得到的是黑白图像，而不是所需的输出，是吗？

from PIL import Image
def draw_nested_rectangles():
    height = int(input('Please enter the overall height: '))
    width = int(input('Please enter the overall width: '))
    size = (width,height)
    pic = Image.new('RGB',size,'white')
    firstRec(width,height)
    secondRec(width,height)
    thirdRec(width,height)
    fourthRec(width,height)
    pic.show()
def firstRec(width,height):
    size = (width,height)
    pic = Image.new('RGB', size, 'white')
    blueProgression = 0
    for x in range(width,width):
        color = (0,0,blueProgression)
        for y in range(height,height):
            pic.putpixel((x,y),color)
        blueProgression += 5
def secondRec(width,height):
    size = (width,height)
    pic = Image.new('RGB', size, 'white')
    greenProgression = 255
    for x in range(int(width*0.15),int(width*0.85)):
        color = (0,greenProgression,0)
        for y in range(int(height*0.15),int(height*0.85)):
            pic.putpixel((x,y),color)
        greenProgression -= 5
def thirdRec(width,height):
    size = (width,height)
    pic = Image.new('RGB', size, 'white')
    greenProgression = 255
    for x in range(int(width*0.30),int(width*0.70)):
        color = (255,0,0)
        for y in range(int(height*0.30),int(height*0.70)):
            pic.putpixel((x,y),color)
def fourthRec(width,height):
    size = (width,height)
    pic = Image.new('RGB', size, 'white')
    greenProgression = 255
    for x in range(int(width*0.45),int(width*0.55)):
        color = (255,255,255)
        for y in range(int(height*0.45),int(height*0.55)):
            pic.putpixel((x,y),color)

我希望输出为四个嵌套的三角形，第一个为宽度和高度的100％（从右侧的黑色开始，逐渐增加为蓝色），第二个嵌套在第一个的70％原始宽度和高度（从左侧开始为黑色，然后逐渐增加为绿色），第三个嵌套在其中，占原来的40％（纯红色），最后一个嵌套在其中，占10％（纯白色）

Answer 1

尝试：-

from PIL import Image



def draw_nested_rectangles():
    global pic
    height = int(input('Please enter the overall height: '))
    width = int(input('Please enter the overall width: '))
    size = (width,height)
    pic = Image.new('RGB', size, 'white')
    firstRec(width, height)
    secondRec(width, height)
    thirdRec(width, height)
    fourthRec(width, height)
    pic.show()

def firstRec(width,height):
    global pic
    size = (width,height)
    blueProgression = 0
    for x in range(width,width):
        color = (0,0,blueProgression)
        for y in range(height,height):
            pic.putpixel((x,y),color)
        blueProgression += 5

def secondRec(width,height):
    global pic
    size = (width,height)
    greenProgression = 255
    for x in range(int(width*0.15),int(width*0.85)):
        color = (0,greenProgression,0)
        for y in range(int(height*0.15),int(height*0.85)):
            pic.putpixel((x,y), color)
        greenProgression -= 5

def thirdRec(width,height):
    global pic
    size = (width,height)
    greenProgression = 255
    for x in range(int(width*0.30),int(width*0.70)):
        color = (255,0,0)
        for y in range(int(height*0.30),int(height*0.70)):
            pic.putpixel((x,y),color)

def fourthRec(width,height):
    global pic
    size = (width,height)
    greenProgression = 255
    for x in range(int(width*0.45),int(width*0.55)):
        color = (255,255,255)
        for y in range(int(height*0.45),int(height*0.55)):
            pic.putpixel((x,y),color)


pic = 0
draw_nested_rectangles()

不良输出的原因：-

之所以获得空白图像而不是预期的图像，是因为您在每个函数内创建了一个单独的pic图像对象，因此所有功能都在单独的图像对象上运行而不是一个。

FIX：-

为了获得所需的输出，必须使用语法pic

将global pic变量定义为全局变量，在每个要使用它的函数中

样品输入：-

Please enter the overall height: 500
Please enter the overall width: 500

样品输出：-

为什么我的输出只是空白的白色图像？ [Python PIL]

1 个答案: