摘要
雖然目前多半的心電圖儀都能將心電圖儲存在記憶體中與列印在紙張上，但是至今還有許多心電圖仍以紙本形式存在舊病歷資料中，這些長久以來所累積記錄在圖紙上的各種心電圖波形，大多已經由專科醫師做過心臟疾病的標記與判讀，所以這些資料在醫學研究與教學訓練上相當具有價值。但是這些舊的紙本心電圖中有許多是繪製在熱感紙上並有嚴重的褪色，因此很難直接使用電腦以數位影像處理來自動數位化。此研究建立了一套處理流程，在電腦將心電圖轉換成數位格式之前，先以人工將變形與不清楚的波形進行調整與描繪。為了確定人工描繪波形的可接受度，計算了各心電圖之間的相關係數與均方根誤差百分比來分析人工描繪所產生的誤差。結果顯示關係數都可達0.97以上，而PRD則可以低到15%左右，此外比較經過人工描繪之正常心電圖的R波自動偵測定位也可確認其影響程度。整體而言，以人工描繪的波形與原始波形之間仍然有相當高的一致性。
並列摘要
Most modern electrocardiographs can store electrocardiograms in memory and printing them out in paper. However, many electrocardiograms are still in paper format kept in old patient records. These electrocardiograms are valuable information for medical research and training because they already have been diagnosed and marked by specialists. Many of these old electrocardiogram were drawn on thermal paper and seriously fading. They are very difficult to be digitized automatically using image processing technique. In this study, a procedure was taken to trace the electrocardiogram by hand before the computerized waveform digitization. The distortion of digitization was analyzed by calculating the percent root-mean-square difference and correlation coefficient of repeated quantization. The results show that the correlation coefficient is generally over 0.97 and the PRD value is around 15%. Automatic detection of position and amplitude of R-wave in electrocardiogram signals was also used to verify the consistence. This study shows that the tracing drawing of signal waveform is highly consistent with the original signal.