Gaze Estimation via a Differential Eyes’Appearances Network with a Reference Grid

A person’s eye gaze can effectively express that person’s intentions.Thus,gaze estimation is an important approach in intelligent manufacturing to analyze a person’s intentions.Many gaze estimation methods regress the direction of the gaze by analyzing images of the eyes,also known as eye patches.However,it is very difficult to construct a person-independent model that can estimate an accurate gaze direction for every person due to individual differences.In this paper,we hypothesize that the difference in the appearance of each of a person’s eyes is related to the difference in the corresponding gaze directions.Based on this hypothesis,a differential eyes’appearances network(DEANet)is trained on public datasets to predict the gaze differences of pairwise eye patches belonging to the same individual.Our proposed DEANet is based on a Siamese neural network(SNNet)framework which has two identical branches.A multi-stream architecture is fed into each branch of the SNNet.Both branches of the DEANet that share the same weights extract the features of the patches;then the features are concatenated to obtain the difference of the gaze directions.Once the differential gaze model is trained,a new person’s gaze direction can be estimated when a few calibrated eye patches for that person are provided.Because personspecific calibrated eye patches are involved in the testing stage,the estimation accuracy is improved.Furthermore,the problem of requiring a large amount of data when training a person-specific model is effectively avoided.A reference grid strategy is also proposed in order to select a few references as some of the DEANet’s inputs directly based on the estimation values,further thereby improving the estimation accuracy.Experiments on public datasets show that our proposed approach outperforms the state-of-theart methods.