MoviePy – Creating Animation Using Matplotlib

In this article we will see how we create animations in MoviePy using matplotlib. MoviePy is a Python module for video editing, which can be used for basic operations on videos and GIF’s. Video is formed by the frames, combination of frames creates a video each frame is an individual image. Matplotlib is a plotting library for the Python programming language and its numerical mathematics extension NumPy. It provides an object-oriented API for embedding plots into applications using general-purpose GUI toolkits like Tkinter, wxPython, Qt, or GTK+.

In order to do this we have to do the following 
1. Import matplotlib modules 
2. Import moviepy modules 
3. Create a numpy array 
4. Create a subplot using matplotlib 
5. Create a Video clip file by calling the make_frame method 
6. Inside the make frame method 
7. Clear the plot and create a new plot using trigonometry methods according to the frame time 
8. Return the plot after converting it into numpy image. 

Below is the implementation 

Python3

# importing matplot lib
import matplotlib.pyplot as plt
import numpy as np

# importing movie py libraries
from moviepy.editor import VideoClip
from moviepy.video.io.bindings import mplfig_to_npimage

# numpy array
x = np.linspace(-2, 2, 200)

# duration of the video
duration = 2

# matplot subplot
fig, ax = plt.subplots()

# method to get frames
def make_frame(t):

    # clear
    ax.clear()

    # plotting line
    ax.plot(x, np.sinc(x**2) + np.sin(x + 2 * np.pi / duration * t), lw = 3)
    ax.set_ylim(-1.5, 2.5)

    # returning numpy image
    return mplfig_to_npimage(fig)

# creating animation
animation = VideoClip(make_frame, duration = duration)

# displaying animation with auto play and looping
animation.ipython_display(fps = 20, loop = True, autoplay = True)

Output :

Moviepy - Building video __temp__.mp4.
Moviepy - Writing video __temp__.mp4

                                                                                                                       
Moviepy - Done !
Moviepy - video ready __temp__.mp4

Another example 

Python3

# importing matplot lib
import matplotlib.pyplot as plt
import numpy as np

# importing movie py libraries
from moviepy.editor import VideoClip
from moviepy.video.io.bindings import mplfig_to_npimage

# numpy array
x = np.linspace(-5, 5, 100)

# duration of the video
duration = 2

# matplot subplot
fig, ax = plt.subplots()

# method to get frames
def make_frame(t):

    # clear
    ax.clear()

    # plotting line
    ax.plot(x, np.sinc(x**2) + np.cos(x + 10 * np.pi / duration * t), lw = 3)
    ax.set_ylim(-1.5, 2.5)

    # returning numpy image
    return mplfig_to_npimage(fig)

# creating animation
animation = VideoClip(make_frame, duration = duration)

# displaying animation with auto play and looping
animation.ipython_display(fps = 20, loop = True, autoplay = True)

Output :

Moviepy - Building video __temp__.mp4.
Moviepy - Writing video __temp__.mp4

                                                                                                                       
Moviepy - Done !
Moviepy - video ready __temp__.mp4