Synchronization

Problem: Multiple filters can modify an image at the same time, causing image corruption.
Solution: Wrap the call to the filter method in a synchronized block based on the layer's intrinsic lock. This ensures that only one thread can modify the layer's image at any given time.

The result of invoking the Invert filter multiple times in rapid succession on a large image

Original image from HubbleSite
Copyright: Public Domain (NASA and ESA)

The rush

There's been a lot of progress, but I'm not sure if I can meet the deadline.

Tasks completed
1. Draw monochrome, RGB and HSB histograms
2. 3 point operations: desaturate, invert, normalize

To-do
1. 3 neighbourhood operations
2. Pencil sketch filter