SPEECH COMPRESSOR WITH GAP FILLING

摘要

An improved speech compressor provides frequency transformation by passing speech signals through an analog shift register and controlling the shift rate of the register with a linearly varying periodicity with noise cancellation of the characteristic noise in the shift registers and the control of the sample period and output blanking to improve the signal output characteristic and minimize noise components therein. The system provides a single compression-expansion manual control which varies the record reproducer transport speed and the rate of change of the linearly varying pulse periodicity to provide a unitary control for selecting the corresponding compression ratio and automatically modifies the sample period to optimize the signal and discard intervals as the selected compression or expansion ratio is changed. Automatic initiation of reset in response to detection of a zero crossing of the audio output signal is provided and auxiliary fixed storage is used to fill blanking gaps in the output signal.