Dipartimento di Medicina Clinica e Sperimentale - Dermatologia, University of Messina, Messina, Italy.
Skin Res Technol. 2014 Feb;20(1):67-73. doi: 10.1111/srt.12085. Epub 2013 May 31.
Despite the importance of images in the discipline and the diffusion of digital imaging devices, the issue of image compression in dermatology was discussed only in few studies, which yielded results often not comparable, and left some unanswered questions.
To evaluate and compare the performance of the JPEG and JPEG2000 algorithms for compression of dermatological images.
Nineteen macroscopic and fifteen videomicroscopic images of skin lesions were compressed with JPEG and JPEG2000 at 18 different compression rates, from 90% to 99.5%. Compressed images were shown, next to uncompressed versions, to three dermatologists with different experience, who judged quality and suitability for educational/scientific and diagnostic purposes. Moreover, alterations and quality were evaluated by calculation of mean 'distance' of pixel colors between compressed and original images and by peak signal-to-noise ratio, respectively.
JPEG2000 was qualitatively better than JPEG at all compression rates, particularly highest ones, as shown by dermatologists' ratings and objective parameters. Agreement between raters was high, but with some differences in specific cases, showing that different professional experience can influence judgement on images.
In consideration of its high qualitative performance and wide diffusion, JPEG2000 represents an optimal solution for the compression of digital dermatological images.
尽管图像在医学领域非常重要，数字成像设备也得到了广泛的应用，但在皮肤科领域，仅有少数研究讨论了图像压缩问题，这些研究的结果往往不可比，并且存在一些未解答的问题。
评估和比较 JPEG 和 JPEG2000 算法在皮肤科图像压缩方面的性能。
将 19 张皮肤病变的宏观图像和 15 张视频显微镜图像使用 JPEG 和 JPEG2000 算法以 18 种不同的压缩率（90%到 99.5%）进行压缩。将压缩后的图像与未压缩的版本一起展示给三位具有不同经验的皮肤科医生，他们根据质量和对教育/科学及诊断目的的适用性进行判断。此外，通过计算压缩图像与原始图像之间像素颜色的平均“距离”以及峰值信噪比，分别评估图像的变化和质量。
JPEG2000 在所有压缩率下的质量均优于 JPEG，尤其是在最高压缩率下，这一点得到了皮肤科医生的评价和客观参数的证实。评分者之间的一致性较高，但在某些特定情况下存在差异，这表明不同的专业经验可能会影响对图像的判断。
考虑到其高质量的性能和广泛的应用，JPEG2000 是数字皮肤科图像压缩的理想解决方案。
