Python: how to capture image from webcam on click using OpenCV

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I want to capture and save a number of images from my webcam using OpenCV. This is my code currently:

import cv2

camera = cv2.VideoCapture(0)
for i in range(10):
    return_value, image = camera.read()
    cv2.imwrite('opencv'+str(i)+'.png', image)
del(camera)

The problem with this is that I do not know when the images are being taken, so a lot of them end up blurry. My question is: Is there a way to have the image taken on the click of a keyboard key?

Also is there a better way to take multiple images, instead of range?

Here is a simple program that displays the camera feed in a cv2.namedWindow and will take a snapshot when you hit SPACE. It will also quit if you hit ESC.

import cv2

cam = cv2.VideoCapture(0)

cv2.namedWindow("test")

img_counter = 0

while True:
    ret, frame = cam.read()
    cv2.imshow("test", frame)
    if not ret:
        break
    k = cv2.waitKey(1)

    if k%256 == 27:
        # ESC pressed
        print("Escape hit, closing...")
        break
    elif k%256 == 32:
        # SPACE pressed
        img_name = "opencv_frame_{}.png".format(img_counter)
        cv2.imwrite(img_name, frame)
        print("{} written!".format(img_name))
        img_counter += 1

cam.release()

cv2.destroyAllWindows()

I think this should answer your question for the most part. If there is any line of it that you don't understand let me know and I'll add comments.

If you need to grab multiple images per press of the SPACE key, you will need an inner loop or perhaps just make a function that grabs a certain number of images.

Note that the key events are from the cv2.namedWindow so it has to have focus.

Python: how to capture image from webcam on click using OpenCV , Here is a simple program that displays the camera feed in a cv2.namedWindow and will take a snapshot when you hit SPACE . It will also quit if you hit ESC . If you need to grab multiple images per press of the SPACE key, you will need an inner loop or perhaps just make a function that grabs a certain number of images. Note that the key events are from the cv2.namedWindow so it has to have focus.

Breaking down your code example

import cv2

imports openCV for usage

camera = cv2.VideoCapture(0)

creates an object called camera, of type openCV video capture, using the first camrea in the list of cameras connected to the computer.

for i in range(10):

tells the program to loop the following indented code 10 times

    return_value, image = camera.read()

read values from the camera object, using it's read method. it resonds with 2 values save the 2 data values into two temporary variables called "return_value" and "image"

    cv2.imwrite('opencv'+str(i)+'.png', image)

use the openCV method imwrite (that writes an image to a disk) and write an image using the data in the temporary data variable

fewer indents means that the loop has now ended...

del(camera)

deletes the camrea object, we no longer needs it.

you can what you request in many ways, one could be to replace the for loop with a while loop, (running forever, instead of 10 times), and then wait for a keypress (like answerred by danidee while I was typing)

or create a much more evil service that hides in the background and captures an image everytime someone presses the keyboard..

kevinam99/capturing-images-from-webcam-using-opencv-python, Capture an image by accessing the webcam of your system and save it to your machine. Softwares and packages required: Python, v3.6.7; Matplotlib, v3.0.2 (to​  Capturing Images from Webcam Using OpenCV Python Capture an image by accessing the webcam of your system and save it to your machine. Softwares and packages required:

i'm not too experienced with open cv but if you want the code in the for loop to be called when a key is pressed, you can use a while loop and an raw_input and a condition to prevent the loop from executing forever

import cv2

camera = cv2.VideoCapture(0)
i = 0
while i < 10:
    raw_input('Press Enter to capture')
    return_value, image = camera.read()
    cv2.imwrite('opencv'+str(i)+'.png', image)
    i += 1
del(camera)

How to take a webcam picture using OpenCV in Python , how-to-take-a-webcam-picture-using-opencv-in-python.py Copy to clipboard⇓ Download. import cv2. video_capture = cv2.VideoCapture(0). Python is a great programming language to work with the webcam. OpenCV is a popular library available for Python that can make it easier to work with videos and webcam. Using this library, you can capture and record webcam video as well as working with videos too. Many of you may think about how to take videos from webcam and save it in the

Here is a simple programe to capture a image from using laptop default camera.I hope that this will be very easy method for all.

import cv2

# 1.creating a video object
video = cv2.VideoCapture(0) 
# 2. Variable
a = 0
# 3. While loop
while True:
    a = a + 1
    # 4.Create a frame object
    check, frame = video.read()
    # Converting to grayscale
    #gray = cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)
    # 5.show the frame!
    cv2.imshow("Capturing",frame)
    # 6.for playing 
    key = cv2.waitKey(1)
    if key == ord('q'):
        break
# 7. image saving
showPic = cv2.imwrite("filename.jpg",frame)
print(showPic)
# 8. shutdown the camera
video.release()
cv2.destroyAllWindows 

You can see my github code here

Capture Videos and Images with Python (Part-2), Use OpenCv library to capture live feed from webcam and also take pictures using Python within 7 lines of code. These are the basic steps for  Highlight: In the previous post we talked how we can manipulate pixels and images in Python using the OpenCV library.Now, it’s time to focus our attention to videos. In this post, you will learn some basic operations which are necessary for building your computer vision applications.

How to access cameras using OpenCV with Python, Do you know how can I find this camera to capture image with it? Using cap = cv2​.VideoCapture(0) zero, the camera found is the webcam. Alright, so my post Getting Webcam Images with Python and OpenCV 2 was wrong! I did not fully understand how to read the OpenCV API documentation and instead of demonstrating how to capture an image with OpenCV 2, I just demonstrated a way to capture an image with OpenCV 1.x in a way different from the example I first followed.

Capture webcam with Python (OpenCV): step by step, Capturing Images from Camera using Python and DirectShow Using OpenCV in Python is a very good solution to prototype vision applications, The image will be retrieved from the callback function passed as parameter  In this video, we will learn the following topics: Capturing still images using webcam and OpenCV Converting Captured image into gray scale image Source Co

Capturing Images from Camera using Python and DirectShow , We will then display the video on a OpenCV window. Introduction In this tutorial we will learn how to obtain video from a webcam, using Python and OpenCV. In our case, the image will be the captured frame from the camera. After you click the ESC key of your keyboard, the window with the video  Capture an image from the webcam of your system and save it to your machine. - kevinam99/capturing-images-from-webcam-using-opencv-python