In this article, we will discuss how to draw a filled rectangle on every frame of video through OpenCV in Python.
Stepwise Implementation:
- Import the required libraries into the working space.
- Read the video on which you have to write.
Syntax:
cap = cv2.VideoCapture(“path”)
- Create an output file using cv2.VideoWriter_fourcc() method. Here you will have options of video formats.
Syntax:
output = cv2.VideoWriter(“output.avi”, cv2.VideoWriter_fourcc(*’MPEG’), 30, (1080, 1920))
- Then edit the frames of the video by adding shapes to it (In our case it is a filled rectangle). We will use the cv2.rectangle() method. This method is used to draw a rectangle on any image.
Syntax:
cv2.rectangle(frame, (100, 100), (500, 500), (0, 255, 0), -1)
- Then write all the frames in the video file.
Syntax:
output.write(frame)
Example:
In this example, we add a green rectangle to the video.
Input Video:
Python3
import cv2 def main(): # reading the input cap = cv2.VideoCapture("input.mp4") output = cv2.VideoWriter( "output.avi", cv2.VideoWriter_fourcc(*'MPEG'), 30, (1080, 1920)) while(True): ret, frame = cap.read() if(ret): # adding filled rectangle on each frame cv2.rectangle(frame, (100, 150), (500, 600), (0, 255, 0), -1) # writing the new frame in output output.write(frame) cv2.imshow("output", frame) if cv2.waitKey(1) & 0xFF == ord('s'): break else: break cv2.destroyAllWindows() output.release() cap.release() if __name__ == "__main__": main() |
Output:
