Convert single pixel AprilTag images to custom bitmap sizes without distortion

processAprilTagImages.sh

#!/bin/bash

# resizse 1 pixel AprilTag to 300x300 without blurring
mogrify -path out -filter box -resize 300x300 tag36_11_0*

# remove 29 pixels from around the outside if required
mogrify -path shaved -shave 29x29 *.png 

# Run multiple commands over multiple CPUs with 100 operations per thread
find . -name "*.png" | xargs -P8 -n100 mogrify -path out -filter box -resize 300x300

# Convert white background in markers to transparent
find . -name "*.png" | xargs -P8 -n100  convert {} -transparent White {} \;  

You need to install ImageMagick for these scripts: imagemagick.org