A survey on mouth modeling and analysis for Sign Language recognition

© 2015 IEEE.Around 70 million Deaf worldwide use Sign Languages (SLs) as their native languages. At the same time, they have limited reading/writing skills in the spoken language. This puts them at a severe disadvantage in many contexts, including education, work, usage of computers and the Internet. Automatic Sign Language Recognition (ASLR) can support the Deaf in many ways, e.g. by enabling the development of systems for Human-Computer Interaction in SL and translation between sign and spoken language. Research in ASLR usually revolves around automatic understanding of manual signs. Recently, ASLR research community has started to appreciate the importance of non-manuals, since they are related to the lexical meaning of a sign, the syntax and the prosody. Nonmanuals include body and head pose, movement of the eyebrows and the eyes, as well as blinks and squints. Arguably, the mouth is one of the most involved parts of the face in non-manuals. Mouth actions related to ASLR can be either mouthings, i.e. visual syllables with the mouth while signing, or non-verbal mouth gestures. Both are very important in ASLR. In this paper, we present the first survey on mouth non-manuals in ASLR. We start by showing why mouth motion is important in SL and the relevant techniques that exist within ASLR. Since limited research has been conducted regarding automatic analysis of mouth motion in the context of ALSR, we proceed by surveying relevant techniques from the areas of automatic mouth expression and visual speech recognition which can be applied to the task. Finally, we conclude by presenting the challenges and potentials of automatic analysis of mouth motion in the context of ASLR

Final Report to NSF of the Standards for Facial Animation Workshop

The human face is an important and complex communication channel. It is a very familiar and sensitive object of human perception. The facial animation field has increased greatly in the past few years as fast computer graphics workstations have made the modeling and real-time animation of hundreds of thousands of polygons affordable and almost commonplace. Many applications have been developed such as teleconferencing, surgery, information assistance systems, games, and entertainment. To solve these different problems, different approaches for both animation control and modeling have been developed

Realistic Lip Syncing for Virtual Character Using Common Viseme Set

Speech is one of the most important interaction methods between the humans. Therefore, most of avatar researches focus on this area with significant attention. Creating animated speech requires a facial model capable of representing the myriad shapes the human face expressions during speech. Moreover, a method to produce the correct shape at the correct time is also in order. One of the main challenges is to create precise lip movements of the avatar and synchronize it with a recorded audio. This paper proposes a new lip synchronization algorithm for realistic applications, which can be employed to generate synchronized facial movements among the audio generated from natural speech or through a text-to-speech engine. This method requires an animator to construct animations using a canonical set of visemes for all pair wise combination of a reduced phoneme set. These animations are then stitched together smoothly to construct the final animation

Three-dimensional linear modeling of tongue: articulatory data and models

Volume images of tongue were acquired by MRI from one subject uttering a corpus representative of French allophone articulations. Supplementary images of hard palate, jaw, and hyoid bone were acquired by CT. The three-dimensional tongue surface outline was represented, for each of the 46 articulations of the corpus, by a mesh obtained by fitting a generic mesh to the set of tongue contours traced from the MR images. Jaw and hyoid bone positions were also determined. The set of the 3D coordinates of all vertices of the tongue mesh constituted the variables on which linear component analysis was applied. Six linearly independent components were found to explain 87 % of the variance of the tongue data. The associated parameters that control the linear articulator tongue model are related to jaw and hyoid positions, and to the actions of tongue muscles such as the genioglossus, the hyoglossus or the styloglossus. In addition, it was shown that the full 3D tongue surface is predictable from its 2D midsagittal contour with a mere 13.6 % increase in the overall full 3D reconstruction RMS error, which confirms quantitatively previous results. Finally, the tongue volume was found to depart by at most ±5% from its mean over the corpus, which supports the hypothesis of tongue tissue incompressibility for speech

Neural Modeling and Imaging of the Cortical Interactions Underlying Syllable Production

This paper describes a neural model of speech acquisition and production that accounts for a wide range of acoustic, kinematic, and neuroimaging data concerning the control of speech movements. The model is a neural network whose components correspond to regions of the cerebral cortex and cerebellum, including premotor, motor, auditory, and somatosensory cortical areas. Computer simulations of the model verify its ability to account for compensation to lip and jaw perturbations during speech. Specific anatomical locations of the model's components are estimated, and these estimates are used to simulate fMRI experiments of simple syllable production with and without jaw perturbations.National Institute on Deafness and Other Communication Disorders (R01 DC02852, RO1 DC01925

Example Based Caricature Synthesis

The likeness of a caricature to the original face image is an essential and often overlooked part of caricature production. In this paper we present an example based caricature synthesis technique, consisting of shape exaggeration, relationship exaggeration, and optimization for likeness. Rather than relying on a large training set of caricature face pairs, our shape exaggeration step is based on only one or a small number of examples of facial features. The relationship exaggeration step introduces two definitions which facilitate global facial feature synthesis. The first is the T-Shape rule, which describes the relative relationship between the facial elements in an intuitive manner. The second is the so called proportions, which characterizes the facial features in a proportion form. Finally we introduce a similarity metric as the likeness metric based on the Modified Hausdorff Distance (MHD) which allows us to optimize the configuration of facial elements, maximizing likeness while satisfying a number of constraints. The effectiveness of our algorithm is demonstrated with experimental results