I have a python script in the same folder as a video I want to convert to a numpy array. My video is called 'test.mp4'.
Within my script, I want to call someFunction('test.mp4') and get back a numpy array. The resulting numpy array should be a numpy array of images, where each image is a 3-d numpy array.
Does that make sense?
Thanks!
skvideo is a python package can be used to read video and stores into the multi-dimensional array.
import skvideo.io
videodata = skvideo.io.vread("video_file_name")
print(videodata.shape)
For more details: http://www.scikit-video.org/stable/index.html and http://mllearners.blogspot.in/2018/01/scikit-video-skvideo-tutorial-for.html
The script below does what you want. You may separate part of it into the function.
Code below doesn't check for errors, in particular, production code will check that every frame* variable is greater than zero.
import cv2
import numpy as np
cap = cv2.VideoCapture('test.mp4')
frameCount = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
frameWidth = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
frameHeight = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
buf = np.empty((frameCount, frameHeight, frameWidth, 3), np.dtype('uint8'))
fc = 0
ret = True
while (fc < frameCount and ret):
ret, buf[fc] = cap.read()
fc += 1
cap.release()
cv2.namedWindow('frame 10')
cv2.imshow('frame 10', buf[9])
cv2.waitKey(0)
When we look to the video from image processing perspective, we can assume that it is a sequence of images.
From this point, you can loop over the frames of your video and convert them into a numpy array.
Here is an example with Pillow and OpenCV libraries, where I'm converting the screenshots from my webcam into numpy arrays:
import cv2
import numpy as np
from PIL import Image, ImageOps
def screenshot():
global cam
cv2.imwrite('screenshot.png', cam.read()[1])
if __name__ == '__main__':
np.set_printoptions(suppress=True)
cam = cv2.VideoCapture(0) # You can replace it with your video path
while True:
ret, img = cam.read()
cv2.imshow('My Camera', img)
ch = cv2.waitKey(5)
if ch == 27:
break
screenshot()
data = np.ndarray(shape=(1, 224, 224, 3), dtype=np.float32)
image = Image.open('screenshot.png')
size = (224, 224) # Put your suitable size
image = ImageOps.fit(image, size, Image.ANTIALIAS)
image_array = np.asarray(image) # Here, an image -> numpy array
print(image_array)
cv2.destroyAllWindows()