User-Transparent LZ77 Steganography

Recently, demand for high-speed compression has lead to new algorithms based on pure Lempel-Ziv compression without entropy coding. Examples are Snappy and LZ4, both using byte based LZ77 algorithms. This leaves significant redundancy on the table that can be used for steganography while remaining completely transparent to the users of ...

more ...

Natural Order String Comparisons in C

I wrote a simple natural string order comparison function in C. I later found out I basically reimplemented (a part of) Martin Pool's strnatcmp, so I renamed mine that as well.

The idea is that in many cases the string "foo10bar" should sort after "foo9bar" instead of in between ...

more ...

Hash Prioritized Treaps

In looking for a data structure for a memory management problem I tried to find a self-balancing tree that would use as little space as possible. The only one I found from Wikipedia that didn't require any additional information at nodes was the scapegoat tree.

Unfortunately, it's not ...

more ...

Ray-Sphere Intersection

I'm writing a small raytracer to familiarize myself with Java. Obviously many of the main algorithms need to be as fast as possible in order to eventually get to real time speeds.

Here's my optimized version of a ray-sphere intersect check. It can probably be tweaked further: 9 ...

more ...