python tkinter:如何处理像素? [英] python tkinter: how to work with pixels?

问题描述

使用谷歌(和这个网站)我看到了一些类似的问题，但我的问题仍然存在:

using google (and this site) i have seen some similar questions but my problem is still here:

我想绘制一个图像(不读取文件)，能够操纵该图像中每个像素的颜色."

"i want to draw an image (without reading a file) , being able to manipulate every single pixel's colour in that image."

我看到另一个问题，建议这样做:

i have seen another question where was suggested to do something like this:

from tkinter import *
A=Tk()
B=Canvas(A)
B.place(x=0,y=0,height=256,width=256)
for a in range(256):
    for b in range(256):
        B.create_line(a,b,a+1,b+1,fill=pyList[a][b])#where pyList is a matrix of hexadecimal strings
A.geometry("256x256")
mainloop()

事实上这回答了我的问题，但是......它非常慢.我应该如何处理 1920x1080 的图像?等我死?

in fact this answers my question but... it is extremely slow. what should i do with a 1920x1080 image ? wait for my death?

所以我要求执行与上述代码相同但更快的方式

so i am asking something to perform the same as the above code but in a faster way

我找到了一种改进 jsbueno 建议的方法的方法，在链接的页面中有解释:

i have found a way to improve the method suggested by jsbueno , it is explained in the page linked :

为什么 Photoimage 放慢?

推荐答案

确实很棘手 --我以为您必须使用 Canvas 小部件，但它也无法访问 Pixels.不过，嵌入在画布中的图像项目确实有.Tkinter.PhotoImage 类确实有一个put"接受十六进制格式和像素坐标的颜色的方法:

It is indeed tricky -- I thought you had to use a Canvas widget, but that has no access to Pixels either. Image items embedded in the Canvas do have, though. The Tkinter.PhotoImage class does have a "put" method that accepts a color in hex format and pixel coordinates:

from tkinter import Tk, Canvas, PhotoImage, mainloop
from math import sin

WIDTH, HEIGHT = 640, 480

window = Tk()
canvas = Canvas(window, width=WIDTH, height=HEIGHT, bg="#000000")
canvas.pack()
img = PhotoImage(width=WIDTH, height=HEIGHT)
canvas.create_image((WIDTH/2, HEIGHT/2), image=img, state="normal")

for x in range(4 * WIDTH):
    y = int(HEIGHT/2 + HEIGHT/4 * sin(x/80.0))
    img.put("#ffffff", (x//4,y))

mainloop()

好消息是，即使以这种方式进行，更新也是实时"的:您在图像上设置像素，然后看到它们显示在屏幕上.

The good news is that even it being done this way, the updates are "live": you set pixels on the image, and see them showing up on screen.

这应该比在屏幕上绘制更高级别的线条快得多 -但是对于很多像素，它仍然会很慢，因为需要一个 Python 函数调用每个像素.任何其他直接操作像素的纯 Python 方式都会受到影响 - 唯一的出路是从 Python 代码中调用在本机代码中一次操作多个像素的基元.

This should be much faster than the way drawing higher level lines on screen - but for lots of pixels it still will be slow, due to a Python function call needed for every pixel. Any other pure python way of manipulating pixels directly will suffer from that - the only way out is calling primitives that manipulate several pixels at a time in native code from your Python code.

一个很好的跨平台库，用于获取 2d 绘图，但文档也很差是开罗 - 它应该有比 Tkinter 的 Canvas 或 PhotoImage 更好的原语.

A nice cross-platform library for getting 2d drawing, however poorly documented as well is Cairo - it would should have much better primitives than Tkinter's Canvas or PhotoImage.

这篇关于python tkinter:如何处理像素?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！