Integer algorithm of lapped biorthogonal transform compression method with GPU

Compression/Decompression of huge terrain data is an important component of GC (Geometry Clipmap) method which has significant impact on rendering speed. Integral lapped biorthogonal transform (binLBT) method was used to reduce the complexity of computation by converting float point operations which spent lots of time in LBT method to integer operations and shift operations. In order to avoid the condition the data bigger than memory in graphic card, the method divided the data into some pitches which fit the memory and load one pitch each time, and then used CUDA (compute unified device architecture) to accomplish binLBT step which supports the parallel features of GPGPU (general purpose computing on graphics processing units). Experiment results show that this method based on binLBT by GPU can improve the efficiency of compression/decompression of huge terrain data and accelerate the rendering speed of GC.