【用戶】安身立命
【年級】國二下
【評論內容】Differential pulse-code modulation (DPCM) is a signal encoder that uses the baseline of pulse-code modulation (PCM) but adds some functionalities based on the prediction of the samples of the signal. The input can be an analog signal or a digital signal.If the input is a continuous-time analog signal, it needs to be sampled first so that a discrete-time signal is the input to the DPCM encoder.
【用戶】安身立命
【年級】國二下
【評論內容】誤差訊號編碼(differential pulse code modulation),以下簡稱(DPCM)是預測編碼中最常使用的一種。在DPCM裡,實際之取樣值與預測值相減得一誤差值,此誤差值在經過量化與編碼後送出。和Delta編碼不同的是,DPCM使用較精確的預測氣而且他的輸出也不再是只有兩種值。DPCM的壓縮效能主要決定於預測器與量化器設計優劣。