Share Email Print

Journal of Medical Imaging • Open Access

Block selective redaction for minimizing loss during de-identification of burned in text in irreversibly compressed JPEG medical images
Author(s): David A. Clunie; Dan Gebow

Paper Abstract

Deidentification of medical images requires attention to both header information as well as the pixel data itself, in which burned-in text may be present. If the pixel data to be deidentified is stored in a compressed form, traditionally it is decompressed, identifying text is redacted, and if necessary, pixel data are recompressed. Decompression without recompression may result in images of excessive or intractable size. Recompression with an irreversible scheme is undesirable because it may cause additional loss in the diagnostically relevant regions of the images. The irreversible (lossy) JPEG compression scheme works on small blocks of the image independently, hence, redaction can selectively be confined only to those blocks containing identifying text, leaving all other blocks unchanged. An open source implementation of selective redaction and a demonstration of its applicability to multiframe color ultrasound images is described. The process can be applied either to standalone JPEG images or JPEG bit streams encapsulated in other formats, which in the case of medical images, is usually DICOM.

Paper Details

Date Published: 25 March 2015
PDF: 6 pages
J. Med. Imag. 2(1) 016501 doi: 10.1117/1.JMI.2.1.016501
Published in: Journal of Medical Imaging Volume 2, Issue 1
Show Author Affiliations
David A. Clunie, PixelMed (United States)
Dan Gebow, MDDX Research & Informatics (United States)

© SPIE. Terms of Use
Back to Top