UInt12Arrays.jl is a Julia package to support the use of arrays of 12-bit unsigned integers and their elements. This package's main purpose is to provide a UInt12Array type that allows for the indexing into arrays of packed UInt12s.

Dealing with 12-bit integers is challenging because the the underlying LLVM integer support is based on integers that are a multiple of a byte (8-bits). For integer types that are a multiple of a byte, see BitIntegers.jl.

To use unsigned 12-bit integers (UInt12) in computations, it is easiest to load them as unsigned 16-bit integers (UInt16). However, to conserve memory it may be advantageous to keep the 12-bit integers packed into a dense array.

1. Provide a UInt12Array that allows for indexing of arrays of packed UInt12s.
2. Allow access of 12-bit integers as type UInt16 (default element type of UInt12Array)
3. Provides a prototype UInt12 type that boxes a UInt16 and implement 12-bit arithmetic
4. Provides lookup table (LUT) and single instruction multiple data (SIMD) methods for unpacking 12-bit data

As mentioned in the background, there is better hardware and compiler support for UInt16. Additionally the supporting code for UInt12 is under development with the main implementation being a boxed UInt16.