apriltag detect

[bleulake]

I photographed april tag using raspberry pi 4 B+(8GB), arducam IMX298 MIPI 16MP Color Camera.
The shooting mode is width 1920 * height 1080.
I want to extract the coordinate values for each corner of the april tag from the picture I took.

When I type the command on the last line I get the message below
Let me know what to fix

(cv) pi@raspberrypi:~ $ python
Python 3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0] on linux
Type “help”, “copyright”, “credits” or “license” for more information.

import apriltag
import cv2
image = cv2.imread(“test.jpg”)
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
options = apriltag.DetectorOptions(families=“tag36h11”)
detector = apriltag.Detector(options)
results = detector.detect(gray)
warning: too many borders in contour_detect (max of 32767!)
Segmentation fault

[crackwitz]

please post your pictures.

[sataki.mostafa]

Please refer here. There is an example in this regard.

[crackwitz]

that is not an april tag. that is a QR code.

you need to post the exact picture that causes the error.

[Supra]

@Bleulake. Can you post contour_detect function?

[crackwitz]

why would you tell someone to use “sudo”? there are enough reasons to not use sudo.

[bleulake]

I attach a picture

[crackwitz]

is that a screenshot of a screenshot?

try otsu thresholding, then give the result of that to the apriltag library

or… contact the author of the package. he’s responsible for supporting his package: https://pypi.org/project/apriltag/

[Eduardo]

The following repository contains the official AprilTag 3 code.

There is Python binding, see the Wiki.
Else, there is also: lib-dt-apriltags: Python bindings for the Apriltags library

The white border is needed for correct AprilTag detection. You should not remove it.

The printed tag should be like this (from this link):

For your image, it gives with the first repo: