Unsharp masking and its inverse processing integrated in a compression/decompression scheme: application to cardiac angiograms

TLDR: A compression scheme based on full-frame DCT which allows the integration of enhancement in the codec and an inverse filter is studied and integrated in the decompression process, so that a non-enhanced image can be derived after enhancement and compression.

Abstract: Image data compression can be useful for storage or transmission of cardiac angiograms In clinical systems, images are recorded in a `raw' format, and are usually processed with an edge enhancement filter to improve the visibility of medical information The raw images are needed for other processing including quantitative measurements, and their enhanced version is used for display We report on a compression scheme based on full-frame DCT which allows the integration of enhancement in the codec We investigated whether the raw or the enhanced image should be compressed We studied an inverse filter and integrated it in the decompression process, so that a non-enhanced image can be derived after enhancement and compression The de-enhancement filter acts as a low pass filter for the quantization noise We proposed to improve the inverse filter using a regularized signal restoration technique