Finding allophones: an evaluation on consonants in the TIMIT corpus

Phonemic analysis, the process of identifying the contrastive sounds in a language, involves finding allophones; phonetic variants of those contrastive sounds. An algorithm for finding allophones (developed by Peperkamp et al.) is evaluated on consonants in the TIMIT acoustic phonetic transcripts. A novel phonetic filter based on the active articulator is introduced and has a higher recall than previous filters. The combined retrieval performance, measured by area under the ROC curve, is 83%. The system implemented can process any language transcribed in IPA and is currently being used to assist the phonemic analysis of unwritten languages.