Recognitionwith raw canonical phonetic movement and handshape subunits on videos of continuous Sign Language

The visual processing of Sign Language (SL) videos offers multiple interdisciplinary challenges for image processing and recognition. Based on tracking and visual feature extraction, we investigate SL visual phonetic modeling by exploiting statistical subunit (SU) models of movement-position and handshape. We further propose a new framework to construct a data-driven lexicon that retains phonetics´ movement information and to perform automatic recognition of continuous SL videos. We construct phonetically meaningful transition SU, named as raw canonical phonetic subunits (SU-CanRaw). Then, we integrate via a Hidden Markov Model multistream scheme the SU-CanRaw extended for both hands, with handshape SU, based on our previous work on Affine-invariant Shape-Appearance Models. By applying the all-inclusive framework on continuous SL videos, we automatically generate a data-driven lexicon that can be further exploited, for automatic analysis of SL corpora, and continuous SL recognition. The recognition experiments, conducted on a newly acquired continuous SL corpus, lead to promising results.