Convert from socket data to numpy array

Question

All welcome.

I'm trying to display a picture sent by sockets.

There is such a code: P.S Yes, yes, I know that this is the worst thing you have seen, but here it is:

while True:
    data = s.recv(BUFFER_SIZE)
    if data:
        print ("received data:", len(data))
        try:
            myfile = open("t.png", 'wb')
            myfile.write(data)
            img = cv2.imread('t.png')
            if img is not None:
                img = cv2.resize(img, (1280, 720))
                cv2.imshow("1", img)
                cv2.waitKey(1)
        except IOError as e:
            print(e)

He opens the file, writes the image there, and then opencv reads this image and shows it.

How can opencv display an image right away?

In order not to burn the picture to disk and read, and immediately show.

(you should prefer `if img is not None:` compare to `if not img is None:`) — Dorian Turba, Jan 18 '19 at 21:06

score 2 · Accepted Answer · answered Jan 18 '19 at 23:08

2

This converts the data (string) received from the socket into an OpenCV image:

img = cv2.imdecode(np.fromstring(data, np.uint8), 1)

The answer in wwii's comment has similar code but more clutter.

answered Jan 18 '19 at 23:08

Ulrich Stern

10,761
5
55
76

Convert from socket data to numpy array

1 Answers1