A Memory Efficient No List SPECK (NSK) Wavelet Image Coder for Memory-constrained Applications

Abstract

In this paper, a fast and memory-efficient listless version of set-partitioned embedded block (SPECK) image coder is proposed. Due to the use of linked lists, the original SPECK algorithm requires large run-time memory, making it unsuitable for memory-constrained applications. The proposed coder replaces linked list with small fixed size static memory, to keep track of blocks in set partitioning only and use only two markers to facilitate coding. Replacement of linked lists with small fixed-size static memory also reduces the memory access time, thereby making it faster than the original SPECK. Simulation results show that the proposed algorithm outperforms SPECK image coder in terms of memory requirement and computational complexity while retaining the coding efficiency and scalability. The proposed coder requires 0.25-bit per pixel state memory which is 3.125% of the memory to store the image. These features make it suitable for resource-constrained portable handheld multimedia devices.

Keywords: Image coding, wavelet, SPECK, listless image coder, memory efficient image coder, block based coding