Direct data compression of ECG signal for telemedicine

Several techniques have been developed during the last four decades for the compression of ECG signal. The ECG signal compression is required for two main reasons, effective and economic data storage and on-line transmission of the signal. However, in present information technology (IT) the ECG data compression has become more significant for Telemedicine. Hence, it is essential to review the existing direct data compression (DDC) techniques for the purpose of telemedicine. This paper deals with efficient algorithms which have been developed after carrying out an exhaustive study of methods such as amplitude zone time epoch coding (AZTEC), modified AZTEC, Fan and scan along polygonal approximation (SAPA) techniques. In each of these techniques, modifications have been made to make it suitable for telemedicine purposes. Suitability of the system has been checked over transport control protocol (TCP), internet protocol (IP), local area network (LAN) and wide area network (WAN). The techniques have been tested for all standard leads of ECG signal of CSE database. The results of improved direct data compression techniques are encouraging and promise wider scope for application in telemedicine.