[zheshishei]

Can the synchronizer differentiate between single block and double block heights?

Also, another cool level of granularity (if needed) could be using 1x2 or 1x1 lego blocks to add more information that's easily seen in the photo. Not only do you have different colors of 1x2 and 1x1 blocks, you can also place them in different positions (left/right vertically, top/bottom horizontally).

All in all, great idea. I'd like to set one of these up myself in the future.

[pasiaj]

I've been playing around with this same kind of idea.

In my case I was using a cheap Android phone as a camera. Color recognition of 1x1 size Legos start to become problematic from more than 2 meters away, even in good lighting conditions.

[zheshishei]

Couldn't it be solved by only taking a picture of the changed columns of the calendar instead of the entire three months?

I'm not familiar with how you're processing the picture, but it might be possible to identify the columns by utilizing the empty row at the top of each column. I count 7 positions/bits. You can use 2 bits to mark the month and the remaining 5 bits to mark the day of the month. Using this encoding, you could even add a fourth month without any problems.