Preliminary validation of content-based compression of mammographic images

This paper presents some preliminary validation results from the content-based compression (CBC) of digitized mammograms for transmission, archiving, and, ultimately, telemammography. Unlike traditional compression techniques, CBC is a process by which the content of the data is analyzed before the compression takes place. In this approach the data is partitioned into two classes of regions and a different compression technique is performed on each class. The intended result achieves a balance between data compression and data fidelity. For mammographic images, the data is segmented into two non-overlapping regions: (1) background regions, and (2) focus-of-attention regions (FARs) that contain the clinically important information. Subsequently, the former regions are compressed using a lossy technique, which attains large reductions in data, while the latter regions are compressed using a lossless technique in order to maintain the fidelity of these regions. In this case, results show that compression ratios averaging 5-10 times greater than that of lossless compression alone can be achieved, while preserving the fidelity of the clinically important information.