Question: I have an algorithm, which after each iteration creates a matrix. After some operations on matrix it is plotted to the user. if I run program 6 times I will get:

[![a bunch of images](https://i.stack.imgur.com/9Rcc7.jpg)](https://i.stack.imgur.com/9Rcc7.jpg)

My goal is to changing image dynamically, like a movie. 

I have no idea from which side to start. I found some ways of creating video from images in python and then wrap it in the video player. But it seems to be a bit complicated and it is impossible to see the changes while algorithm is working. Are there any suggestions how to do it?

Answer: 
You can use [FFMPEG](https://www.ffmpeg.org/)

```
def convert():
    os.system("ffmpeg -r 1 -i img%01d.png -vcodec mpeg4 -y movie.mp4")

```

Alternatively, you can use [ImageIO](http://imageio.github.io/) to generate a GIF. You can set the parameters for duration of each frame.

```
import imageio
with imageio.get_writer('/path_to_video.gif', mode='I') as writer:
    for filename in filenames:
        image = imageio.imread(filename)
        writer.append_data(image)

```

Read the manual on website for more detailed instructions.

Or [with cv2](https://stackoverflow.com/questions/14440400/creating-a-video-using-opencv-2-4-0-in-python),

```
import cv2

img1 = cv2.imread('1.jpg')
img2 = cv2.imread('2.jpg')
img3 = cv2.imread('3.jpg')

height , width , layers =  img1.shape

video = cv2.VideoWriter('video.avi',-1,1,(width,height))

video.write(img1)
video.write(img2)
video.write(img3)

cv2.destroyAllWindows()
video.release()

```
Video Data Generation code from scratch in Python (use Jupyter):

```
import numpy as np
import skvideo.io as sk
# creating sample video data
num_vids = 5
num_imgs = 100
img_size = 50
min_object_size = 1
max_object_size = 5

for i_vid in range(num_vids):
 imgs = np.zeros((num_imgs, img_size, img_size)) # set background to 0
 vid_name = ‘vid’ + str(i_vid) + ‘.mp4’
 w, h = np.random.randint(min_object_size, max_object_size, size=2)
 x = np.random.randint(0, img_size — w)
 y = np.random.randint(0, img_size — h)
 i_img = 0
 while x>0:
 imgs[i_img, y:y+h, x:x+w] = 255 # set rectangle as foreground
 x = x-1
 i_img = i_img+1
 sk.vwrite(vid_name, imgs.astype(np.uint8))
# play a video
from IPython.display import Video
Video(“vid3.mp4”) # the script & video should be in same folder

```