caa a22 4500 463178874 CHVBK 20180406164833.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s10278-007-9013-z doi (NATIONALLICENCE)springer-10.1007/s10278-007-9013-z Quality of Compressed Medical Images [Elektronische Daten] [Ya-Hui Shiao, Tzong-Jer Chen, Keh-Shih Chuang, Cheng-Hsun Lin, Chun-Chao Chuang] Previous studies have shown that Joint Photographic Experts Group (JPEG) 2000 compression is better than JPEG at higher compression ratio levels. However, some findings revealed that this is not valid at lower levels. In this study, the qualities of compressed medical images in these ratio areas (∼20), including computed radiography, computed tomography head and body, mammographic, and magnetic resonance T1 and T2 images, were estimated using both a pixel-based (peak signal to noise ratio) and two 8 × 8 window-based [Q index and Moran peak ratio (MPR)] metrics. To diminish the effects of blocking artifacts from JPEG, jump windows were used in both window-based metrics. Comparing the image quality indices between jump and sliding windows, the results showed that blocking artifacts were produced from JPEG compression, even at low compression ratios. However, even after the blocking artifacts were omitted in JPEG compressed images, JPEG2000 outperformed JPEG at low compression levels. We found in this study that the image contrast and the average gray level play important roles in image compression and quality evaluation. There were drawbacks in all metrics that we used. In the future, the image gray level and contrast effect should be considered in developing new objective metrics. Society for Imaging Informatics in Medicine, 2007 Image quality nationallicence JPEG nationallicence JPEG2000 nationallicence image compression nationallicence Shiao Ya-Hui Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut Chen Tzong-Jer Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut Chuang Keh-Shih Department of Nuclear Science, National Tsing-Hua University, Hsinchu, Taiwan aut Lin Cheng-Hsun Department of Radiological Technology, Central Taiwan University of Science and Technology, Taichung, Taiwan aut Chuang Chun-Chao Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut Journal of Digital Imaging Springer-Verlag 20/2(2007-06-01), 149-159 0897-1889 20:2<149 2007 20 10278 https://doi.org/10.1007/s10278-007-9013-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10278-007-9013-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shiao Ya-Hui Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut NATIONALLICENCE 700 1- Chen Tzong-Jer Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut NATIONALLICENCE 700 1- Chuang Keh-Shih Department of Nuclear Science, National Tsing-Hua University, Hsinchu, Taiwan aut NATIONALLICENCE 700 1- Lin Cheng-Hsun Department of Radiological Technology, Central Taiwan University of Science and Technology, Taichung, Taiwan aut NATIONALLICENCE 700 1- Chuang Chun-Chao Department of Medical Imaging Technology, Shu-Zen College of Medicine and Management, 82144, Luju Shiang, Kaohsiung, Taiwan aut NATIONALLICENCE 773 0- Journal of Digital Imaging Springer-Verlag 20/2(2007-06-01), 149-159 0897-1889 20:2<149 2007 20 10278 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer