Hornof W J, Ballance D W, Nyland T G, Koblik P D, Crabb-Hartman A
Department of Surgical and Radiological Sciences, School of Veterinary Medicine, Univ. of California, Davis 95616, USA.
Vet Radiol Ultrasound. 1999 Mar-Apr;40(2):179-82. doi: 10.1111/j.1740-8261.1999.tb01906.x.
The lossless capture of the entire range of optical densities encountered in a radiograph can require up to 4000 individual shades of gray. Most inexpensive computer displays, and most grayscale image formats contain only 256 gray shades. To use these systems, a look up table must be generated to display the scanned image, which maps the approximately 4000 gray shades in the digitized radiograph to the 256 gray shades on the monitor. However, if this conversion is inappropriately performed, much of the information contained in the original image could be lost. This study was undertaken to develop an histogram equalization algorithm that would automatically convert the 4000 gray shade digitized radiograph into a 256 gray shade image file, without perceptable loss of diagnostic information or image quality.
在一张X光片中无损捕捉遇到的整个光密度范围可能需要多达4000种不同的灰度。大多数廉价的电脑显示器以及大多数灰度图像格式仅包含256种灰度。为了使用这些系统，必须生成一个查找表来显示扫描图像，该查找表将数字化X光片中大约4000种灰度映射到显示器上的256种灰度。然而，如果这种转换执行不当，原始图像中包含的许多信息可能会丢失。本研究旨在开发一种直方图均衡化算法，该算法能自动将4000灰度的数字化X光片转换为256灰度的图像文件，而不会造成可察觉的诊断信息丢失或图像质量下降。
