Threshold based lossy compression of medical ultrasound images using contourlet transform

In this paper we present a new contourlet based lossy image compression method for medical ultrasound images. In this algorithm we use contourlet transform for image decomposition. Then, we apply a new thresholding process on the coefficients before quantization. We select the threshold due to coefficients occurrence in the contourlet domain. This algorithm has the ability of simultaneous speckle reduction using another thresholding. Due to this time saving ability, the algorithm can be used in online image transmission systems. We implement our method on a real ultrasound images and ultrasound phantom image. Results proved that our proposed method has acceptable performance and good performance over common compression methods such as wavelet based SPIHT in the case of PSNR.