Capturing a single image from my webcam in Java or Python

Solution 1:

@thebjorn has given a good answer. But if you want more options, you can try OpenCV, SimpleCV.

using SimpleCV (not supported in python3.x):

from SimpleCV import Image, Camera

cam = Camera()
img = cam.getImage()
img.save("filename.jpg")

using OpenCV:

from cv2 import *
# initialize the camera
cam = VideoCapture(0)   # 0 -> index of camera
s, img = cam.read()
if s:    # frame captured without any errors
    namedWindow("cam-test",CV_WINDOW_AUTOSIZE)
    imshow("cam-test",img)
    waitKey(0)
    destroyWindow("cam-test")
    imwrite("filename.jpg",img) #save image

using pygame:

import pygame
import pygame.camera

pygame.camera.init()
pygame.camera.list_cameras() #Camera detected or not
cam = pygame.camera.Camera("/dev/video0",(640,480))
cam.start()
img = cam.get_image()
pygame.image.save(img,"filename.jpg")

Install OpenCV:

install python-opencv bindings, numpy

Install SimpleCV:

install python-opencv, pygame, numpy, scipy, simplecv

get latest version of SimpleCV

Install pygame:

install pygame

Solution 2:

On windows it is easy to interact with your webcam with pygame:

from VideoCapture import Device
cam = Device()
cam.saveSnapshot('image.jpg')

I haven't tried using pygame on linux (all my linux boxen are servers without X), but this link might be helpful http://www.jperla.com/blog/post/capturing-frames-from-a-webcam-on-linux

Solution 3:

import cv2
camera = cv2.VideoCapture(0)
while True:
    return_value,image = camera.read()
    gray = cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
    cv2.imshow('image',gray)
    if cv2.waitKey(1)& 0xFF == ord('s'):
        cv2.imwrite('test.jpg',image)
        break
camera.release()
cv2.destroyAllWindows()

Solution 4:

Some time ago I wrote simple Webcam Capture API which can be used for that. The project is available on Github.

Example code:

Webcam webcam = Webcam.getDefault();
webcam.open();
try {
  ImageIO.write(webcam.getImage(), "PNG", new File("test.png"));
} catch (IOException e) {
  e.printStackTrace();
} finally {
  webcam.close();
}

Solution 5:

I wrote a tool to capture images from a webcam entirely in Python, based on DirectShow. You can find it here: https://github.com/andreaschiavinato/python_grabber.

You can use the whole application or just the class FilterGraph in dshow_graph.py in the following way:

from pygrabber.dshow_graph import FilterGraph
import numpy as np
from matplotlib.image import imsave

graph = FilterGraph()
print(graph.get_input_devices())
device_index = input("Enter device number: ")
graph.add_input_device(int(device_index))
graph.display_format_dialog()
filename = r"c:\temp\imm.png"
# np.flip(image, axis=2) required to convert image from BGR to RGB
graph.add_sample_grabber(lambda image : imsave(filename, np.flip(image, axis=2)))
graph.add_null_render()
graph.prepare()
graph.run()
x = input("Press key to grab photo")
graph.grab_frame()
x = input(f"File {filename} saved. Press key to end")
graph.stop()