A improved version for PLWAH
A detailed survey is introduced in the following paper.
[1] Zhen Chen et al., “A Survey of Bitmap Index Compression Algorithms for Big Data,” Tsinghua Science and Technology, 20(1), pp.100-115, February 2015.
URL: http://ieeexplore.ieee.org/xpls/articleDetails.jsp?arnumber=7040519.