Thanks a ton for testing it quite exhaustively! Would really appreciate it if you can share the second image.

I spent a lot of time working on a hack for 'normalizing' white on black and black on white backgrounds and also between choosing adaptive vs gaussian thresholds dynamically during preprocessing.

Here is an example with white on black and black on white variations of Nike logo that works as intended.

http://compute.vision/nouns/index.html?barnacles=https://s3....

http://compute.vision/nouns/index.html?barnacles=https://s3....

Edit: Grammar