Effects of Packet Losses in Waveform Coded Speech and Improvements Due to an Odd-Even Sample-Interpolation Procedure

摘要: We have studied the effects of random packet losses in digital speech systems based on 12-bit PCM and 4-bit adaptive DPCM coding. The are a function length B probability loss P L . also tbe benefits an odd-even sample-interpolation procedure that mitigates these (at cost increased decoding delay). is arranging 2B -block codewords into two -sample packets, odd-sample even-sample packet. If one packets lost, odd (or even) samples estimated from even odd) by means interpolation. Perceptual considerations indicate lengths most robust to range 16-32 ms, irrespective whether interpolation used or not. With lengths, tolerable values, which strictly input-speech-dependent, can be as high 2 5 percent without 10 with These observations computer simulation three sentence-length inputs, informal listening tests.