An improved JPEG compression method for digital hologram based on adaptive quantization table

Abstract

In the field of holography applications, compressing digital holograms is of increasing interest, and the standardization of hologram compression technology is a general trend. In this paper, we present an improved hologram compression method based on an adaptive JPEG quantization table. Initially, the hologram spectrum undergoes pre-processing to remove background noise. This pre-processing step makes the hologram spectrum more amenable to quantization. Subsequently, a formula for generating different adaptive quantization tables is proposed which can generate different adaptive quantization table for different holograms. The pre-processed hologram image is then quantized using this adaptive JPEG quantization table, followed by entropy encoding to further improve the compression ratio of the hologram. Simulation and experimental results show that the presented method improves the compression ratio of holograms while ensuring high-quality reconstruction compared to the JPEG standard. The PSNR value of the reconstructed image from compressed hologram reached 28.3642 dB, the MS-SSIM value was 0.8944, and the achieved compression ratio reached 97.35.