Applications of image compression have been gaining importance over the years in medical fields. The medical imaging modalities produced a large amount of information on all levels of hospital care. This information, in the form of images, needs to be stored for future references. While compressing the medical images, it is necessary to maintain high diagnostic quality with a high compression rate. Several image compression approaches have been developed towards the direction of the storage space problem in such a way that the doctors accurately and reliably diagnose the patient’s diseases from the reconstructed image after decompression. A high compression ratio is required to reduce the storage space due to the large size of medical images. Fractal image compression is a lossy technique to compress the image in a coded form instead of pixels and is differentiated by its long encoding time with a high compression ratio, resolution-independent, fast decoding, and self-similarity. The main purpose of this paper is to present a comparative performance study of the three coding schemes of fractal compression for grayscale medical images based on fixed partition. The first two coding schemes are based on the pixel-pattern measure and the third scheme is a proposed method based on the fractal dimension for complexity measure of range and domain blocks. The comparative study included encoding time, peak signal to noise ratio, and compression ratio, as a result, has been accomplished.

多年来，图像压缩的应用在医学领域变得越来越重要。医学成像方式在医院的各个层次上产生了大量的信息。需要以图像形式存储此信息，以备将来参考。在压缩医学图像时，必须以高压缩率保持高诊断质量。已经朝着存储空间问题的方向发展了几种图像压缩方法，以使得医生在减压之后根据重建的图像准确而可靠地诊断患者的疾病。由于医学图像的大尺寸，需要高压缩比以减小存储空间。分形图像压缩是一种以编码形式而不是像素形式压缩图像的有损技术，它的特点是编码时间长，压缩率高，分辨率独立，解码速度快且具有自相似性。本文的主要目的是针对基于固定分区的灰度医学图像的分形压缩的三种编码方案进行比较性能研究。前两种编码方案基于像素模式量度，而第三种方案是基于分形维数的范围和域块复杂度量度的建议方法。结果，比较研究包括编码时间，峰值信噪比和压缩比。快速解码和自相似。本文的主要目的是针对基于固定分区的灰度医学图像的分形压缩的三种编码方案进行比较性能研究。前两种编码方案基于像素模式量度，而第三种方案是基于分形维数的范围和域块复杂度量度的建议方法。结果，比较研究包括编码时间，峰值信噪比和压缩比。快速解码和自相似。本文的主要目的是针对基于固定分区的灰度医学图像的分形压缩的三种编码方案进行比较性能研究。前两种编码方案基于像素模式量度，而第三种方案是基于分形维数的范围和域块复杂度量度的建议方法。结果，比较研究包括编码时间，峰值信噪比和压缩比。前两种编码方案基于像素模式量度，而第三种方案是基于分形维数的范围和域块复杂度量度的建议方法。结果，比较研究包括编码时间，峰值信噪比和压缩比。前两种编码方案基于像素模式量度，而第三种方案是基于分形维数的范围和域块复杂度量度的建议方法。结果，比较研究包括编码时间，峰值信噪比和压缩比。