Opencv Webcam code example

Example 1: opencv webcam python

import numpy as np
import cv2

cap = cv2.VideoCapture(0)

while(True):
    # Capture frame-by-frame
    ret, frame = cap.read()

    # Our operations on the frame come here
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

    # Display the resulting frame
    cv2.imshow('frame',gray)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

# When everything done, release the capture
cap.release()
cv2.destroyAllWindows()

Example 2: how to open webcam with python

import cv2

cap = cv2.VideoCapture(0)

# Check if the webcam is opened correctly
if not cap.isOpened():
    raise IOError("Cannot open webcam")

while True:
    ret, frame = cap.read()
    frame = cv2.resize(frame, None, fx=0.5, fy=0.5, interpolation=cv2.INTER_AREA)
    cv2.imshow('Input', frame)

    c = cv2.waitKey(1)
    if c == 27:
        break

cap.release()
cv2.destroyAllWindows()

Example 3: how to read video in opencv python

import numpy as np
import cv2
cap = cv2.VideoCapture('videos/wa.avi')
while(cap.isOpened()):
  ret, frame = cap.read()
  gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
  cv2.imshow('frame',gray)
  if cv2.waitKey(1) & 0xFF == ord('q'):
    break

cap.release()
cv2.destroyAllWindows()

Example 4: access webcam using opencv

import cv2

cap = cv2.VideoCapture(0)

while True:
  ret, frame = cap.read()
  
  cv2.imshow('webcam feed' , frame)
  if cv2.waitKey(1) & 0xFF == ord(' '):
    break
    
cap.release()
cv2.destroyAllWindows()

#by using the spacebar you will be able to finish the process of video capturing
#in opencv and the window will close

Example 5: read live video from usb opencv python

import cv2
cap = cv2.VideoCapture()
# The device number might be 0 or 1 depending on the device and the webcam
cap.open(0, cv2.CAP_DSHOW)
while(True):
    ret, frame = cap.read()
    cv2.imshow('frame', frame)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break
cap.release()
cv2.destroyAllWindows()

Example 6: Opencv Webcam

import cv2
frameWidth = 640
frameHeight = 480
cap = cv2.VideoCapture(0)
cap.set(3, frameWidth)
cap.set(4, frameHeight)
cap.set(10,150)
while True:
    success, img = cap.read()
    cv2.imshow("Result", img)
    if cv2.waitKey(1) and 0xFF == ord('q'):
        break