In recent years, skeleton detection based on side-output network has shown significant effectiveness. However, the existing methods are still unable to tackle the problem of image distortion in side-output structure caused by high-multiplier up/down-sampling, and the fixed receptive field limits the feature expression of the networks. To solve these problems, this paper proposes a local short-connection unidirectional fusion network based on side-output connection, which includes a feature extraction network and a side-output connection network. The feature extraction network is a deep convolutional neural network, which is used for multi-layer feature extraction. The side-output connection network consists of a local short-connection unit and a unidirectional fusion network. The local short-connection gradually constructs the continuous large receptive field features by integrating the adjacent features of receptive field, while the unidirectional fusion of multi-scale features from deep to shallow can achieve the characterization of the object from rough to fine. Experimental results on four commonly used skeleton detection datasets demonstrate the effectiveness of the proposed method.
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