The impact of lossless image compression to radiographs

Abstract

The increasing number of digital imaging modalities results in data volumes of several Tera Bytes per year that must be transferred and archived in a common-sized hospital. Hence, data compression is an important issue for picture archiving and communication systems (PACS). The effect of lossy image compression is frequently analyzed with respect to images from a certain modality supporting a certain diagnosis. However, novel compression schemes have been developed recently allowing efficient but lossless compression.In this study, we compare the lossless compression schemes embedded in the tagged image file format (TIFF), graphics interchange format (GIF), and Joint Photographic Experts Group (JPEG 2000 II) with the Borrows-Wheeler compression algorithm (BWCA) with respect to image content and origin. Repeated measures ANOVA was based on 1.200 images in total.Statistically significant effects (p < 0,0001) of compression scheme, image content, and image origin were found. Best mean compression factor of 3.5 (2.272 bpp) is obtained applying BTW to secondarily digitized radiographs of the head, while the lowest factor of 1,05 (7.587 bpp) resulted from the TIFF packbits algorithm applied to pelvis images captured digitally. Over all, the BWCA is slightly but significantly more effective than JPEG 2000. Both compression schemes reduce the required bits per pixel (bpp) below 3. Also, secondarily digitized images are more compressible than the directly digital ones. Interestingly, JPEG outperforms BWCA for directly digital images regardless of image content, while BWCA performs better than JPEG on secondarily digitized radiographs. In conclusion, efficient lossless image compression schemes are available for PACS.

Intelligent visually lossless compression of dental images

“…This has led to studies intended on the design of appropriate techniques (see Foos et al, 1999;Wu et al, 2003;Fidler and Likar, 2007;Kim et al, 2010;Georgiev et al, 2013;Al-Shebani et al, 2019;Ye et al, 2019 and references therein). The influence of lossy compression on image diagnostic properties has been investigated (Eraso et al, 2002;Lehmann et al, 2006;Braunschweig et al, 2009). The appropriateness of the idea of visually lossless compression has been confirmed (Slone et al, 2000;Kocsis et al, 2003).…”

SPIE Medical Imaging 50th anniversary: history of the Picture Archiving and Communication Systems Conference

“…As imaging examination data continued to grow, the impact on archives was a topic of interest 498 , 499 as was compression. 500 Interventional radiology and surgical workflows were discussed. 501 – 503 Standards papers were prominent including approaches for structured reporting, 504 DICOM-RT for radiation therapy, 505 and document sharing with the IHE cross-enterprise document sharing profile (XDS).…”