Add SVG format or larger files

[josh-zheng]

Our team was trying to print the tags, for which the images were too small. I'm not aware of a quicker way to scale the images up rather than writing a numpy script. Having SVG or larger images would be really helpful for printing a lot of tags more efficiently.

Of course if there is a better solution, I would be interested to hear it as I've not worked with tagging before.

[UberEclectic]

Did you check the other repo, mentioned in the README of this one? The generator makes PostScript files, which is indeed a scalable vector format.

https://github.com/AprilRobotics/apriltag-generation

HTH

[UberEclectic]

If you are using one of the stock tag formats, google for 'apriltag pdf' and you can find some premade tags that take up an entire page.

[sgilsonator]

See my issue which includes an attached PDF I generated from the PS file containing all of the tag36h11 fiducials, one page each for printing on a letter sized sheet.

https://github.com/AprilRobotics/apriltag-imgs/issues/4#issue-501435628

[biocrypto730]

The images from the repo scale perfectly when using Google Docs to stretch the image, then exporting to a PDF. They appear blurry in the Google Docs pane but when you export them, they are clear.

[swinterbotix]

@biocrypto730,

Thanks for the tip! I tried using Google Docs, and it worked for me as well!

[hardesh]

@biocrypto730 Thanks a lot!

[ShiweiJin]

@biocrypto730 I tried this method. However, the tag has some grey block area that shan't appear. Is this result correct?

[pbeeson]

Any image processing program (gimp, etc.) should scale the .png images to any size you want. You just need to make sure to tell it not to interpolate when scaling up, so it doesn't "blur" the larger image.

[cbteeple]

In case anyone is still interested in a solution for resizing these pre-built images to a specified size and arranging them in a grid for easy printing, see my recent comment in Issue #4. I wrote a bash script to take care of this (only tested in Ubuntu though).

[ejs94]

I created a script using the pillow library to resize the tags and save it to a pdf, it can be accessed through this https://gist.github.com/ejs94/65a6d663427ba21eaa8b6305d3f51b22 It is currently being possible to choose the family, id, size in mm and dpi for printing.

[ScottJohnson2718]

Was it a size problem with Github where the posted images need to be so small? I have my own version of the tag generator in C++ that uses OpenCV and I can generate the tags in any size I want. I currently generate them as 160x160 pixels which preview in Windows Explorer perfectly. I also use them as textures in Unity. The original poster asked for SVG or larger images. I have larger images. tag36h11 zips up in 340KB so I'll try posting a sample here. tag36h11_legacy.zip

[arnoldad]

FWIW: I just created this PR which includes a simple native python3 script that can create an svg from the tag png files they supply: https://github.com/AprilRobotics/apriltag-imgs/pull/9

It works great for my own use which requires that i generate tags of a known size.