Variable date-rate recording on a PC using MPEG-Audio Layer III

Layer III of the MPEG-Audio coding standard supports variable data-rate recording. This can be used to further reduce the storage requirements of high-qualtiy digital audio signals. A compression factor of more than 12:1 can be reached for high quality audio signals at a bandwidth of 20 kHz. A new version of the encoder has been implemented which supports the variable-rate feature. A PC-based system using one internal board to encode and decode two channels of audio data using Layer III cariale rate coding is presented.