camera-streaming.py

import datetime
import os
import sys
from threading import Thread
from argparse import ArgumentParser
import io

from flask import Flask, render_template, Response
from flask import send_file

from pypylon import pylon
from pypylon import genicam
import cv2

app = Flask(__name__)

__author__ = "[email protected]"
__date__ = "03/02/2019"
__version__ = "0.1"
__description__ = ""

global cam

class Camera(Thread):
    def __init__(self, fps):
        Thread.__init__(self)
        os.environ["PYLON_CAMEMU"] = "1"
        try:
            cam = pylon.InstantCamera(pylon.TlFactory.GetInstance().CreateFirstDevice())
            cam.AcquisitionFrameRateEnable = True
            cam.AcquisitionFrameRateAbs = fps
            cam.Open()
            cam.StartGrabbing(pylon.GrabStrategy_LatestImageOnly) 
            print("Using device ", cam.GetDeviceInfo().GetModelName())
        except genicam.GenericException as e:
            # Error handling
            print("An exception occurred.", e)
        self.cam = cam
        self.buffered_photo = None
        self.daemon = True
        self.start()
    def run(self):
        while True:
            try:
                grabResult = self.cam.RetrieveResult(5000, pylon.TimeoutHandling_ThrowException)
                frame = grabResult.Array
            except genicam.GenericException as e:
                print("An exception occurred.", e)
                continue
            ret, buffer = cv2.imencode('.jpg', frame)
            self.buffered_photo = buffer.tobytes()
    def frames_generator(self):
        while True:
            yield (b'--frame\r\n'
                        b'Content-Type: image/jpeg\r\n\r\n' + self.buffered_photo + b'\r\n')  # concat frame one by one and show result
            
@app.route('/video_feed')
def video_feed():
    global cam
    """Video streaming route. Put this in the src attribute of an img tag."""
    return Response(cam.frames_generator(),
                    mimetype='multipart/x-mixed-replace; boundary=frame')

@app.route('/capture_photo')
def capture_photo():
    global cam
    return send_file(
        io.BytesIO(cam.buffered_photo),
        mimetype='image/jpeg')

if __name__ == '__main__':
    argParser = ArgumentParser(description=__description__, 
                            epilog='Developed by ' + __author__ + ' in ' + __date__)
    argParser.add_argument('--fps', dest="fps", type=str, default='8')
    argParser.add_argument('--port', dest="port", type=str, default='8080')
    args = argParser.parse_args()
    
    global cam
    cam = Camera(int(args.fps))
    
    app.run(host='0.0.0.0', port=args.port, debug=True)