如何在Python中使用PIL将图像合成到另一个图像上？

Question

我需要拍摄一张图片并将其放置在新生成的白色背景上,以便将其转换为可下载的桌面壁纸.所以这个过程会:

1. 生成具有1440x900尺寸的全新白色图像
2. 将现有图像放在顶部,居中
3. 保存为单张图片

在PIL中,我看到了ImageDraw对象,但没有任何迹象表明它可以将现有图像数据绘制到另一个图像上.任何人都可以推荐的建议或链接？

Answer 1

这可以使用Image实例的paste方法完成:

from PIL import Image
img = Image.open('/path/to/file', 'r')
img_w, img_h = img.size
background = Image.new('RGBA', (1440, 900), (255, 255, 255, 255))
bg_w, bg_h = background.size
offset = ((bg_w - img_w) // 2, (bg_h - img_h) // 2)
background.paste(img, offset)
background.save('out.png')

这个和许多其他PIL技巧可以在Nadia Alramli的PIL教程中学习

Answer 2

基于unutbus答案:

#!/usr/bin/env python

from PIL import Image
import math


def resize_canvas(old_image_path="314.jpg", new_image_path="save.jpg",
                  canvas_width=500, canvas_height=500):
    """
    Place one image on another image.

    Resize the canvas of old_image_path and store the new image in
    new_image_path. Center the image on the new canvas.
    """
    im = Image.open(old_image_path)
    old_width, old_height = im.size

    # Center the image
    x1 = int(math.floor((canvas_width - old_width) / 2))
    y1 = int(math.floor((canvas_height - old_height) / 2))

    mode = im.mode
    if len(mode) == 1:  # L, 1
        new_background = (255)
    if len(mode) == 3:  # RGB
        new_background = (255, 255, 255)
    if len(mode) == 4:  # RGBA, CMYK
        new_background = (255, 255, 255, 255)

    newImage = Image.new(mode, (canvas_width, canvas_height), new_background)
    newImage.paste(im, (x1, y1, x1 + old_width, y1 + old_height))
    newImage.save(new_image_path)

resize_canvas()

请记住使用Pillow(Documentation,GitHub,PyPI)代替python-imaging,因为Pillow可以与Python 2.X和Python 3.X一起使用.

Answer 3

这是做类似的事情

我首先在 Photoshop 中生成“白色背景”并将其导出为 PNG 文件。这就是我得到 im1 的地方（图 1）。然后使用粘贴功能，因为它更容易。

from PIL import Image

im1 = Image.open('image/path/1.png')
im2 = Image.open('image/path/2.png')
area = (40, 1345, 551, 1625)  
im1.paste(im2, area)
                   l>(511+40) l>(280+1345)
         |    l> From 0 (move, 1345px down) 
          -> From 0 (top left, move 40 pixels right)

Okay so where did these #'s come from? (40, 1345, 551, 1625) im2.size (511, 280) Because I added 40 right and 1345 down (40, 1345, 511, 280) I must add them to the original image size which = (40, 1345, 551, 1625)

im1.show() 

展示您的新形象