OpenCV Load Video from a capture card or OBS Studio FaceRecogition

Question

I'm creating a proof of concept, I have a CCTV Setup & the only output i have access to is a HDMI port, can I use say a capture card or OBS, as an input for openCV all the code i've looked at uses a raspberry pi with a PiCam an. so im just a little lost on limitations of functionality

Answer 1

This works for me using USB HDMI capture card:

#!/usr/bin/env python

import numpy as np
import cv2

import datetime, time

import os, sys

cap = cv2.VideoCapture(0)

cv2_version_major = int(cv2.__version__.split('.')[0])

if cv2_version_major > 3 :
    cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1920)
    cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 1280)
else :  # before 3.0
    cap.set( cv2.cv.CV_CAP_PROP_FRAME_WIDTH, 1920)
    cap.set( cv2.cv.CV_CAP_PROP_FRAME_HEIGHT, 1280)

start_time = time.time()
total_frames = 0

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

    # Display the resulting frame
    cv2.imshow('frame', cv2.pyrDown(frame))

    # add some processing here if you like

    total_frames += 1
    fps = total_frames / (time.time() - start_time)
    print 'FPS %.02f   \r' % fps,

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