来自 Django 网页中相机的 Opencv Live Stream

Question

我正在用 Django 做一个项目。我想在网页上显示来自摄像头的实时信息。但是我不确定如何返回从网页上的摄像头获得的实时提要。 这是我迄今为止尝试过但没有看到任何进展的代码。

from django.shortcuts import render
from .forms import FaceAdditionForm
import cv2
import numpy as np
from django.http import StreamingHttpResponse

def capture_video_from_cam():
    cap = cv2.VideoCapture(0)
    currentFrame = 0
    while True:

        ret, frame = cap.read()

        # Handles the mirroring of the current frame
        frame = cv2.flip(frame,1)
        currentFrame += 1

def addfaces(request):
    add_faces_form = FaceAdditionForm()
    if add_faces_form.is_valid():
        add_faces_form.save()
    return render(request, 'base.html', {'add_faces': add_faces_form})


def show_video_on_page(request):
    resp = StreamingHttpResponse(capture_video_from_cam())
    return render(request, 'base.html', {'video': resp})

Answer 1

上述问题的解决方案是这样的：

views.py

from django.views.decorators import gzip
from django.http import StreamingHttpResponse
import cv2
import threading

class VideoCamera(object):
    def __init__(self):
        self.video = cv2.VideoCapture(0)
        (self.grabbed, self.frame) = self.video.read()
        threading.Thread(target=self.update, args=()).start()

    def __del__(self):
        self.video.release()

    def get_frame(self):
        image = self.frame
        _, jpeg = cv2.imencode('.jpg', image)
        return jpeg.tobytes()

    def update(self):
        while True:
            (self.grabbed, self.frame) = self.video.read()


def gen(camera):
    while True:
        frame = camera.get_frame()
        yield(b'--frame\r\n'
              b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')


@gzip.gzip_page
def livefe(request):
    try:
        cam = VideoCamera()
        return StreamingHttpResponse(gen(cam), content_type="multipart/x-mixed-replace;boundary=frame")
    except:  # This is bad! replace it with proper handling
        pass

然后在 urls.py 中将其映射到一个 url。