{'fraction_non_alphanumeric': 0.028242677824267783, 'fraction_numerical': 0.0031380753138075313, 'mean_word_length': 5.018867924528302, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Source controlled variable bit-rate speech coder based on waveform interpolation

This paper describes a source controlled variable bit-rate (SC-VBR) speech coder based on the concept of prototype waveform interpolation. The coder uses a four mode classification : silence, voiced, unvoiced and transition. These modes are detected after the speech has been decomposed into slowly evolving (SEW) and rapidly evolving (REW) waveforms. A voicing activity detection (VAD), the relative level of SEW and REW and the cross-correlation coefficient between characteristic waveform segments are used to make the classification. The encoding of the SEW components is improved using a gender adaptation. In tests using conversational speech, the SC-VBR allows a compression factor of around 3. The VBR coder was evaluated against a fixed rate 4.6kbit/s PWI coder for clean speech and noisy speech and was found to perform better for male speech and for noisy speech.