ORIGINAL ARTICLE Evaluation of JPEG and JPEG2000 compression algorithms for dermatological images KH Gulkesen, †, * A Akman, ‡ YK Yuce, † E Yilmaz, ‡ AA Samur, † F Isleyen, † DS Cakcak, ‡ E Alpsoy ‡ † Department of Biostatistics and Medical Informatics, ‡ Department of Dermatology, Akdeniz University, Medical Faculty, Antalya, Turkey *Correspondence: KH Gulkesen. E-mail: hgulkesen@akdeniz.edu.tr Abstract Background Some image compression methods are used to reduce the disc space needed for the image to store and transmit the image efficiently. JPEG is the most frequently used algorithm of compression in medical systems. JPEG compression can be performed at various qualities. There are many other compression algorithms; among these, JPEG2000 is an appropriate candidate to be used in future. Objective To investigate perceived image quality of JPEG and JPEG2000 in 1 : 20, 1 : 30, 1 : 40 and 1 : 50 compression rates. Methods In total, photographs of 90 patients were taken in dermatology outpatient clinics. For each patient, a set which is composed of eight compressed images and one uncompressed image has been prepared. Images were shown to dermatologists on two separate 17-inch LCD monitors at the same time, with one as compressed image and the other as uncompressed image. Each dermatologist evaluated 720 image couples in total and defined whether there existed any difference between two images in terms of quality. If there was a difference, they reported the better one. Among four dermatologists, each evaluated 720 image couples in total. Results Quality rates for JPEG compressions 1 : 20, 1 : 30, 1 : 40 and 1 : 50 were 69%, 35%, 10% and 5% respectively. Quality rates for corresponding JPEG2000 compressions were 77%, 67%, 56% and 53% respectively. Conclusion When JPEG and JPEG2000 algorithms were compared, it was observed that JPEG2000 algorithm was more successful than JPEG for all compression rates. However, loss of image quality is recognizable in some of images in all compression rates. Received: 15 September 2009; Accepted: 10 November 2009 Keywords data compression, dermatology, photography Conflicts of interest None. Introduction Since digital images have been used in health domain, picture archiving and transmission has become pretty easy. The clinical applications of digital photography are numerous. 1–4 Digital images, including dermatoscopic images, can be used to document clinical information. 5 Changes in skin lesions can readily be docu- mented and monitored through serial imaging. 6 Clinical photogra- phy may also help histopathological diagnosis. 7 Approximately 85% of the dermatologists in New York City use camera and ratio of digital cameras is increasing. 8 Digital photography is also useful in the relatively new area of teledermatology. 9 Although digital imaging is cheaper than conventional methods, digital image archiving and transmission still has a cost. Some compression methods are used to reduce the disc space needed for the image, store and transmit the image efficiently. 10 However, as image quality may have critical value in medicine, each compres- sion method and ratio must be evaluated. Joint Photographic Experts Group (JPEG, JPG) is an image compression standard, which was declared by Joint Photographic Expert Group in 1992. Since then, it has been the predominant image file format, which is used in wide spectrum of applications including World Wide Web and digital photography. It is the most frequently used algorithm of image compression in medicine also. 11 JPEG compression can be performed at various qualities. All digital cameras currently in the market support JPEG format and almost all compact digital cameras are capable of saving ª 2009 The Authors JEADV 2010, 24, 893–896 Journal compilation ª 2009 European Academy of Dermatology and Venereology DOI: 10.1111/j.1468-3083.2009.03538.x JEADV