Narrow Results

We had proposed a novel and fast Electrocardiogram (ECG) signal compression algorithm for non-uniform sampling in time domain [1]. It meets the real-time requirement for clinical application. Moreover, the compression performance is stable and uniform even for abnormal ECG signals. A criterion called sum square difference (SSD) is defined as an error test equation. The algorithm using SSD to calculate error tolerance is applied to the records in MIT-BIH database (with 11-bit resolution and 360 Hz sampling rate). It belongs to the threshold-limited algorithm but [1] does not mention much about this kind of algorithm. In this paper we provide more comparisons among SSD, Fan, scan-along polygonal approximation (SAPA), maximum enclosed area (MEA), and optimization algorithm (OPT) using the two measures called sample compression ratio (SCR) and percent root mean squared difference (PRD) with proper mean offset that [1] does not adopt. The results show SSD outperforms the mentioned algorithms with the same computational complexity O(n). Moreover, the comparison with the best but time-consuming coder OPT (O (n³)) shows how much the algorithm can be improved.