如何使用python创建.png文件？

Question

我正在尝试从uint8array创建一个.png文件但是没有得到预期的结果。该文件是908字节，但它应该是905字节。当我尝试在MS绘图中打开图像时，它会显示这不是有效的位图文件。当我使用node.js时，同样的数组对我有用。
这是代码：

import io
import numpy as np

arr  =[137,80,78,71,13,10,26,10,0,0,0,13,73,72,68,82,0,0,0,200,0,0,0,200,8,6,0,0,0,173,88,174,158,0,0,0,4,115,66,73,84,8,8,8,8,124,8,100,136,0,0,0,9,112,72,89,115,0,0,11,19,0,0,11,19,1,0,154,156,24,0,0,3,43,73,68,65,84,120,156,237,221,193,110,163,48,20,64,209,206,168,255,255,203,51,251,44,174,21,192,177,33,231,236,41,52,237,149,37,30,14,63,63,0,0,0,0,0,0,0,0,0,0,19,253,57,120,220,191,75,175,98,236,232,117,114,15,219,254,63,253,157,121,21,112,119,2,129,32,16,8,2,129,32,16,8,2,129,32,16,8,191,147,126,174,185,5,239,184,250,255,229,178,185,138,21,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,194,172,103,177,222,245,233,61,201,239,58,251,172,208,236,223,111,247,235,59,107,217,179,125,86,16,8,2,129,32,16,8,2,129,32,16,8,2,129,32,16,8,71,231,32,159,190,47,61,251,124,103,231,0,163,227,103,207,41,102,159,127,247,207,255,213,101,215,107,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,126,144,179,102,207,1,70,86,239,199,88,253,93,200,171,63,255,105,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,158,50,7,89,125,159,253,238,251,49,206,218,253,250,14,179,130,64,16,8,4,129,64,16,8,4,129,64,16,8,4,129,64,184,203,28,228,238,239,175,56,59,39,89,189,223,98,247,207,127,26,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,199,62,199,255,97,171,223,15,226,239,56,137,21,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,194,183,236,7,121,250,126,139,213,251,77,86,127,126,211,88,65,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,236,50,7,217,125,63,197,234,227,207,90,125,254,145,109,175,207,10,2,65,32,16,4,2,65,32,16,4,2,65,32,16,4,2,97,245,253,239,171,124,251,156,98,245,241,35,179,247,243,76,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,28,100,246,125,252,145,217,63,223,249,207,157,127,25,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,109,239,63,191,184,251,126,135,167,255,252,213,199,79,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,112,151,57,200,200,234,253,32,171,143,31,121,202,223,249,227,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,238,242,158,244,145,213,239,175,152,109,245,251,73,86,179,31,4,118,36,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,28,100,228,233,251,37,118,127,255,198,215,206,97,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,118,153,131,220,253,62,253,232,252,187,127,111,214,89,219,190,223,227,44,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,93,230,32,171,239,227,143,172,126,15,249,200,234,57,195,234,243,79,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,112,116,14,242,233,231,255,87,239,167,120,250,123,216,71,118,159,83,189,186,236,243,176,130,64,16,8,4,129,64,16,8,4,129,64,16,8,4,129,64,56,122,127,252,177,223,131,196,35,152,131,192,39,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,204,250,110,222,171,247,48,123,182,235,217,182,221,243,110,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,1,0,0,0,0,0,0,0,0,56,239,63,169,44,80,125,75,214,2,231,0,0,0,0,73,69,78,68,174,66,96,130]

arr = np.array(arr, dtype=np.uint8)
np.set_printoptions(formatter={'int':hex})
arr=np.array(arr)
f=open("QR icon.png","w")
f.write(arr)
f.close()

当我在记事本中打开创建的图像时，在我使用节点创建的文件中有一个额外的空间。我想我是以错误的方式创建文件。请帮帮我......

Answer 1

好的，首先你的代码对我不起作用我遇到了一些小错误。当我修复它们时，它解决了你最初的问题：

import io
import numpy as np

arr  =[137,80,78,71,13,10,26,10,0,0,0,13,73,72,68,82,0,0,0,200,0,0,0,200,8,6,0,0,0,173,88,174,158,0,0,0,4,115,66,73,84,8,8,8,8,124,8,100,136,0,0,0,9,112,72,89,115,0,0,11,19,0,0,11,19,1,0,154,156,24,0,0,3,43,73,68,65,84,120,156,237,221,193,110,163,48,20,64,209,206,168,255,255,203,51,251,44,174,21,192,177,33,231,236,41,52,237,149,37,30,14,63,63,0,0,0,0,0,0,0,0,0,0,19,253,57,120,220,191,75,175,98,236,232,117,114,15,219,254,63,253,157,121,21,112,119,2,129,32,16,8,2,129,32,16,8,2,129,32,16,8,191,147,126,174,185,5,239,184,250,255,229,178,185,138,21,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,194,172,103,177,222,245,233,61,201,239,58,251,172,208,236,223,111,247,235,59,107,217,179,125,86,16,8,2,129,32,16,8,2,129,32,16,8,2,129,32,16,8,71,231,32,159,190,47,61,251,124,103,231,0,163,227,103,207,41,102,159,127,247,207,255,213,101,215,107,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,126,144,179,102,207,1,70,86,239,199,88,253,93,200,171,63,255,105,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,158,50,7,89,125,159,253,238,251,49,206,218,253,250,14,179,130,64,16,8,4,129,64,16,8,4,129,64,16,8,4,129,64,184,203,28,228,238,239,175,56,59,39,89,189,223,98,247,207,127,26,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,199,62,199,255,97,171,223,15,226,239,56,137,21,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,194,183,236,7,121,250,126,139,213,251,77,86,127,126,211,88,65,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,236,50,7,217,125,63,197,234,227,207,90,125,254,145,109,175,207,10,2,65,32,16,4,2,65,32,16,4,2,65,32,16,4,2,97,245,253,239,171,124,251,156,98,245,241,35,179,247,243,76,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,28,100,246,125,252,145,217,63,223,249,207,157,127,25,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,109,239,63,191,184,251,126,135,167,255,252,213,199,79,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,112,151,57,200,200,234,253,32,171,143,31,121,202,223,249,227,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,238,242,158,244,145,213,239,175,152,109,245,251,73,86,179,31,4,118,36,16,8,2,129,32,16,8,2,129,32,16,8,2,129,176,203,28,100,228,233,251,37,118,127,255,198,215,206,97,172,32,16,4,2,65,32,16,4,2,65,32,16,4,2,65,32,16,118,153,131,220,253,62,253,232,252,187,127,111,214,89,219,190,223,227,44,43,8,4,129,64,16,8,4,129,64,16,8,4,129,64,16,8,132,93,230,32,171,239,227,143,172,126,15,249,200,234,57,195,234,243,79,99,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,129,112,116,14,242,233,231,255,87,239,167,120,250,123,216,71,118,159,83,189,186,236,243,176,130,64,16,8,4,129,64,16,8,4,129,64,16,8,4,129,64,56,122,127,252,177,223,131,196,35,152,131,192,39,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,8,4,130,64,32,204,250,110,222,171,247,48,123,182,235,217,182,221,243,110,5,129,32,16,8,2,129,32,16,8,2,129,32,16,8,2,1,0,0,0,0,0,0,0,0,56,239,63,169,44,80,125,75,214,2,231,0,0,0,0,73,69,78,68,174,66,96,130]

arr = np.array(arr, dtype=np.uint8)
np.set_printoptions(formatter={'int':hex})
arr=np.array(arr)
f=open("QR icon.png","wb")
f.write(arr.tostring())
f.close()

差异是wb，所以我可以写二进制和arr.tostring()。当我检查属性时，它有905像素。