How to parse mjpeg http stream from ip camera?

Question

Given below is the code written for getting live stream from an IP Camera.

from cv2 import *
from cv2 import cv
import urllib
import numpy as np
k=0
capture=         


        

Answer 1

I don't think the first anwser is fine with other format image data, eg png. So I write the following code, which can handle other type of images

"""
MJPEG format

Content-Type: multipart/x-mixed-replace; boundary=--BoundaryString
--BoundaryString
Content-type: image/jpg
Content-Length: 12390

... image-data here ...


--BoundaryString
Content-type: image/jpg
Content-Length: 12390

... image-data here ...
"""
import io
import requests
import cv2
import numpy as np


class MjpegReader():
    def __init__(self, url: str):
        self._url = url

    def iter_content(self):
        """
        Raises:
            RuntimeError
        """
        r = requests.get(self._url, stream=True)

        # parse boundary
        content_type = r.headers['content-type']
        index = content_type.rfind("boundary=")
        assert index != 1
        boundary = content_type[index+len("boundary="):] + "\r\n"
        boundary = boundary.encode('utf-8')

        rd = io.BufferedReader(r.raw)
        while True:
            self._skip_to_boundary(rd, boundary)
            length = self._parse_length(rd)
            yield rd.read(length)

    def _parse_length(self, rd) -> int:
        length = 0
        while True:
            line = rd.readline()
            if line == b'\r\n':
                return length
            if line.startswith(b"Content-Length"):
                length = int(line.decode('utf-8').split(": ")[1])
                assert length > 0


    def _skip_to_boundary(self, rd, boundary: bytes):
        for _ in range(10):
            if boundary in rd.readline():
                break
        else:
            raise RuntimeError("Boundary not detected:", boundary)

mr = MjpegReader("http://127.0.0.1/mjpeg.cgi")
for content in mr.iter_content():
    i = cv2.imdecode(np.frombuffer(content, dtype=np.uint8), cv2.IMREAD_COLOR)
    cv2.imshow('i', i)
    if cv2.waitKey(1) == 27:
        break