Automated CVR modification for improving perception of stop consonants
Increasing the intensity of the consonant segments relative to the nearby vowel segments, known as consonant-vowel ratio (CVR) modification, is reported to be effective in improving perception of stop consonants for listeners in noisy backgrounds and for hearing-impaired listeners. A technique for automated CVR modification using detection of acoustic landmarks corresponding to the stop release bursts, with high temporal accuracy, is investigated. Its effectiveness in improving perception of stop consonants in the presence of speech-spectrum shaped noise is evaluated by conducting listening tests on five normal-hearing subjects with VCV utterances involving six stop consonants and three vowels. The processing improved the recognition scores for stop consonants by nearly 7, 18, and 25% at SNR levels of 0, -6, and -12 dB, respectively.