使用 imageio 保存 3D 图

Question

我想将 3D 绘图另存为 gif。但是，由于我无法解释的原因，以下代码不起作用。当我使用 imageio.mimsave(...) 时收到错误消息：Image must be 2D (grayscale, RGB, or RGBA)，但我将图像保存为 RGB：

import numpy as np
import matplotlib.pyplot as plt
import imageio

x = [0,1,0,0]
y = [0,0,1,0]
z = [0,0,0,1]

fig = plt.figure(figsize=(15,9))
ax = fig.add_subplot(projection='3d')
ax.scatter(x,y,z,s=1500)

images = []
for n in range(0, 100):
    if n >= 20: 
        ax.azim = ax.azim+1.1 
    fig.canvas.draw()
    image = np.frombuffer(fig.canvas.tostring_rgb(), dtype='uint8')
    images.append(image)
   
imageio.mimsave('test.gif', images)

Answer 1

np.frombufferreturns一个平面数组，它的形状(X*Y*3,)，相反imageio需要一个Y×X × 3（或者对于 RGBA 缓冲区可能是 × 4）。您必须 reshape 您的 image

In [43]: import numpy as np
    ...: import matplotlib.pyplot as plt
    ...: import imageio
    ...: 
    ...: x = [0,1,0,0]
    ...: y = [0,0,1,0]
    ...: z = [0,0,0,1]
    ...: 
    ...: fig = plt.figure(figsize=(5, 3)) # @100 dpi it's 500×300 pixels
    ...: ax = fig.add_subplot(projection='3d')
    ...: ax.scatter(x,y,z,s=500)
    ...: 
    ...: images = []
    ...: for n in range(0, 25):
    ...:     if n >= 15:
    ...:         ax.azim = ax.azim+1.1
    ...:     fig.canvas.draw()
    ...:     image = np.frombuffer(fig.canvas.tostring_rgb(), dtype='uint8')
    ...:     images.append(image.reshape(300, 500, 3)) ## Y×X
    ...: 
    ...: imageio.mimsave('test.gif', images)
    ...: 

In [44]: ls -l test.gif
-rw-r--r-- 1 boffi boffi 825988 May 21 19:46 test.gif

In [45]:

请注意，我已经修改了尺寸和帧数以获得更小的 GIF。

使用 imageio 保存 3D 图

Save 3D plot with imageio

python

image

numpy

matplotlib

python-imageio