Compression technique plays an important role indiagnosis, prognosis and analysis of ischemic heart diseases. It is also preferable for its fast data sending capability in the field of telemedicine. Various techniques have been proposed over years for compression. Among those Discrete Cosine Transformation(DCT), Discrete Wavelet Transformation(DWT), Fast Fourier Transformation(FFT) andWalsh Hadamard Transformation(WHT) are mostly used. In this paper a comparative study of FFT, DCT, DWT, and WHT is proposed using ECG and PPG signal, whichshows a certain relation between them as discussed in previous papers[1]. Image processing depends on compression which helps in reduction of file size for large data transmission in a stipulated and reduced time. Wavelet analysis provides one of the common goals of image compression, i. e. the signal or image clearance and simplification, which are part of denoising or filtering. Wavelet analysis uses and thus provides long term intervals. In this modern era medicinal therapies has evolved drastically which requires transmission of medical data over long distances under high security with maintaining efficacy. This paper delivers a comparative study based on compression ratio and Peak-Signal-to-Noise-Ratio(PSNR) values of image qualities for corresponding techniques . This study alsoascertains the least distortion of PPG signal among 1D signals after retrieval and information extraction from it and ECG signal based on the intermittent relations among ECG and PPG signals as discussed in other papers.

1. Nilanjan Dey, Anamitra Bardhan Roy, Achintya Das, Sheli Sinha Chaudhuri," Stationary Wavelet Transformation Based Self-Recovery of Blind-Watermark from Electrocardiogram Signal in the Wireless Telecardiology", International Workshop on Intelligence and Security Informatics for International Security (IIS'12) , 11-12 October 2012, Trivandrum, India, [Springer in Communications in Computer and Information Science Series(CCIS), ISSN: 1865:0929. CCIS is abstracted/indexed in ISI Proceedings, Scopus, EI and DBLP]
2. Sayantan Mukhopadhyay, Shouvik Biswas, Anamitra Bardhan Roy, Nilanjan Dey, "Wavelet Based QRS Complex Detection of ECG Signal," International Journal of Engineering Research and Applications (IJERA), ISSN: 2248-9622, Vol. 2, Issue 3, May-Jun 2012, pp. 2361-2365[DBLP Indexed]
3. Potdar, Vidysagar and Han, Song and Chang, Elizabeth, "A survey of digital image watermarking techniques", Proceeding of 3rd IEEE-International Conference on Industrial Informatics, Frontier Technologies for the Future of Industry and Business, pp. 709-716, Perth, WA, Aug 10, 2005.
4. Analysis of P-QRS-T Components Modified by Blind Watermarking Technique Within the Electrocardiogram Signal for Authentication in Wireless Telecardiology Using DWT, Nilanjan Dey, Sayantan Mukhopadhyay, AchintyaDas, Sheli Sinha Chaudhuri, International Journal of Image, Graphics and Signal Processing, IJIGSP Vol. 4, No. 7, July 2012
5. Frigo, M. and S. G. Johnson, "FFTW: An Adaptive Software Architecture for the FFT,"Proceedings of the International Conference on Acoustics, Speech, and Signal Processing, Vol. 3, 1998, pp. 1381-1384.
6. . Rader, C. M. , "Discrete Fourier Transforms when the Number of Data Samples Is Prime,"Proceedings of the IEEE, Vol. 56, June 1968, pp. 1107-1108.
7. Nilanjan Dey, Tanmay Bhattacharya, S. R. Bhadra Chowdhury, "A Session based Multiple Image Hiding Technique using DWT and DCT", International Journal of Computer Applications (0975 – 8887), Volume 38– No. 5, January 2012.
8. Mei Jiansheng, Li Sukang. Tan Xiaomei," A Digital Watermarking Algorithm Based On DCT and DWT", Proceedings of the 2009 International Symposium on Web Information Systems and Applications (WISA'09) Nanchang, P. R. China, May 22-24, 2009, pp. 104-107.
9. An Overview of Non-contact Photoplethysmography, Peck Y S Cheang and Peter R Smith, ELECTRONIC SYSTEMS AND CONTROL DIVISION RESEARCH, 2003.
10. Discrete Walsh-Hadamard Transform, http://www. mathworks. in/products/signal/examples. html?file=/products/demos/shipping/signal/walshhadamarddemo. html
11. T. Beer, Walsh Transforms, American Journal of Physics, Vol. 49, Issue 5, May 1981
12. Analysis of Photoplethysmographic Signals Modified by Reversible Watermarking Technique using Prediction-Error in Wireless Telecardiology, Nilanjan Dey, Shouvik Biswas, Anamitra Bardhan Roy, Achintya Das*4, Sheli Sinha Chowdhury, 47th Annual National Convention Of Computer Society Of India, 2012, IEEE Indexed.

Fft Dct Dwt Wht Ecg Ppg