Can't set black_border ? about apriltag HOT 5 CLOSED

Hi!
I've encountered the same problem when I was working with Kalibr.
Here is a patch to do changes mentioned above from border size 1 to border size 2.
tag36h11_border1to2_patch.txt
This patch can be applied just by git apply command.

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Hi,

We no longer allow directly changing the border width (it did not seem to be a useful option). There are two ways you could detect tags with a double wide black border now.

a) You can generate a new tag family with the desired layout using: https://github.com/AprilRobotics/apriltag-generation
This won't have the same pattern of bits though if you have tags already printed out that you need to detect.

b) You can hack the tag36h11.c file to make it detect tags with a double wide black border. Increase width_at_border and total_width by 2, and increase each of the bit_x/bit_y values by 1.

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Thank you for your suggestion.

from apriltag.

Hi,

We no longer allow directly changing the border width (it did not seem to be a useful option). There are two ways you could detect tags with a double wide black border now.

a) You can generate a new tag family with the desired layout using: https://github.com/AprilRobotics/apriltag-generation This won't have the same pattern of bits though if you have tags already printed out that you need to detect.

b) You can hack the tag36h11.c file to make it detect tags with a double wide black border. Increase width_at_border and total_width by 2, and increase each of the bit_x/bit_y values by 1.

I think kalibr is wildly enough used to say that double boarder feature was useful, so I would gently ask you to rethink it. :)

thx for the patch @ishipachev

Updated:
Because the "tag36h11_create" doesn't used internally, there is an alternative way to make it work without patching, simply changing the "apriltag_family_t" content with the following code:

for (uint32_t i=0; i < tf->nbits; ++i) {
   tf->bit_x[i] += 1;
   tf->bit_y[i] += 1;
}
tf->width_at_border += 2;
tf->total_width += 2;

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@zpillio Could you mention where this code need to be placed?

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