A hybrid scheme of image compression employing wavelets and 2D-PCA
2D-PCA; Feature matrix; Image compression; Projection vector; Wavelet structural similarity index
In this paper, we have presented a method of compressing 2D grey-scale images employing wavelets and two-dimensional principal component analysis (2D-PCA). Principal component analysis (PCA) is an already established technique for image compression which primarily aims at exploiting inter pixel redundancies present in the image, while wavelet is a tool widely used in multi-resolution image processing. In the proposed method the image is subjected to a multi-resolution decomposition using wavelet. Subsequently, 2D-PCA is applied on the set of detail images at each level of resolution. The compressed form of the image is constituted by representative pairs of principal components and projection vectors from each level of resolution along with the approximate image at the coarsest resolution. The proposed method requires relatively few number of principal components (of varied dimension) to produce improved compression ratio with acceptable peak signal to noise ratio (PSNR). The method has been implemented and tested on a set of real 2D grey-scale images and the results have been assessed on both qualitative and quantitative basis by measuring parameters like compression ratio (CR), PSNR, structural similarity index measurement (SSIM) and the overall performance is found to be satisfactory. Copyright 2017 Inderscience Enterprises Ltd.
International Journal of Computational Vision and Robotics, Vol-7, No. 5, pp. 522-537.
https://doi.org/10.1504/IJCVR.2017.086275 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85029212783&doi=10.1504%2fIJCVR.2017.086275&partnerID=40&md5=198d4ebaedc93d0f7ec4e49daa82caa3
Mishra M.K., Department of Computer Science, Christ University, Bengaluru, 560029, India; Ghosh R., Nomura Research Institute Financial Technologies, Kolkata, 700106, India; Mukhopadhyay S., Department of Computer Science and Engineering, Indian School of Mines, Dhanbad, 826004, India