A Full Frequency Masking Vocoder for Legal Eavesdropping Conversation Recording
This is an incremental improvement for legal eavesdropping applications, addressing bandwidth constraints in long conversation recordings.
The paper tackled the problem of bandwidth-efficient voice recording for legal eavesdropping by developing a vocoder using full frequency masking and spectral filling techniques, resulting in a method that saves bandwidth while maintaining intelligibility.
This paper presents a new approach for a vocoder design based on full frequency masking by octaves in addition to a technique for spectral filling via beta probability distribution. Some psycho-acoustic characteristics of human hearing - inaudibility masking in frequency and phase - are used as a basis for the proposed algorithm. The results confirm that this technique may be useful to save bandwidth in applications requiring intelligibility. It is recommended for the legal eavesdropping of long voice conversations.