将海龟输出保存为 jpeg

Question

我有一个分形图像创建器。它创建了一个随机分形树之类的东西。完成后，它会提示用户保存树。我现在将它保存为 .svg 并且有效，但我希望它保存为更方便的文件类型，例如 jpeg。有任何想法吗？ 代码：

import turtle
import random
from sys import exit
from time import clock
import canvasvg
turtle.colormode(255)
red = 125
green = 70
blue = 38        
pen = 10
def saveImg():
    print("Done.")
    save = input("Would you like to save this tree? Y/N \n")
    if save.upper() == "Y":
        t.hideturtle()
        name = input("What would you like to name it? \n")
        nameSav = name + ".svg"
        ts = turtle.getscreen().getcanvas()
        canvasvg.saveall(nameSav, ts)
    elif save.upper() == "N":
        def runChk():
            runAgain = input("Would you like to run again? Y/N (N will exit)")
            if runAgain.upper() == "Y":
                print("Running")
                main()
            elif runAgain.upper() == "N":
                print("Exiting...")
                exit()
            else:
                print("Invalid response.")
                runChk()
        runChk()
    else:
        print("Invalid response.")
        saveImg()

def tree(branchLen, t, red, green, blue, pen):
    time = str(round(clock()))
    print("Drawing... " + time)
    if branchLen > 3:
        pen = pen*0.8
        t.pensize(pen)
        if (red > 10 and green < 140):
            red = red - 15
            green = green + 8
    if branchLen > 5:
        angle = random.randrange(18, 55)
        angleTwo = 0.5*angle
        sub = random.randrange(1,16)
        t.color(red, green, blue)
        t.forward(branchLen)
        t.right(angleTwo)
        tree(branchLen-sub,t, red, green, blue, pen)
        t.left(angle)
        tree(branchLen-sub, t, red, green, blue, pen)
        t.right(angleTwo)
        t.backward(branchLen)

def main():
    t = turtle.Turtle()
    myWin = turtle.Screen()
    t.speed(0)
    t.hideturtle()
    t.left(90)
    t.up()
    t.backward(100)
    t.down()
    print("Please wait while I draw...")
    tree(random.randrange(60,95),t,red,green,blue, pen)
    saveImg()
main()

Answer 1

它必须是 JPEG 格式吗？ PNG就足够了吗？

如果是这样，您可以使用cairosvg 将 SVG 转换为 PNG。不幸的是，canvasvg.saveall() 只允许您向其传递将写入 SVG 的文件名，因此您需要为 SVG 使用临时文件，然后使用 cairosvg.svg2png() 将该临时文件转换为 PNG。所以像这样的东西应该可以完成这项工作：

import os
import shutil
import tempfile

import canvasvg

name = raw_input("What would you like to name it? \n")
nameSav = name + ".png"
tmpdir = tempfile.mkdtemp()  # create a temporary directory
tmpfile = os.path.join(tmpdir, 'tmp.svg')  # name of file to save SVG to
ts = turtle.getscreen().getcanvas()
canvasvg.saveall(tmpfile, ts)
with open(tmpfile) as svg_input, open(nameSav, 'wb') as png_output:
    cairosvg.svg2png(bytestring=svg_input.read(), write_to=png_output)
shutil.rmtree(tmpdir)  # clean up temp file(s)

如果您愿意，您可以基于canvasvg.saveall()（它非常小）编写自己的saveall() 函数，该函数接受类似文件的对象而不是文件名，并写入该对象。然后你可以传入一个StringIO 对象，而不必费心处理临时文件。或者您的 saveall() 可以将 SVG 数据作为字节字符串返回。