Sparse subspace clustering (SSC), as an effective subspace clustering technique, has been widely applied in the remote sensing community, demonstrating a superior performance over the traditional methods such as k-means. In this paper, we propose a unified framework for hyperspectral image (HSI) clustering, which incorporates spatial information and label information in an SSC model, aiming at generating a more precise similarity matrix. The spatial information is included through a joint sparsity constraint on the coefficient matrix of each local region. Pixels within a local region are encouraged to select a common set of samples in the subspace-sparse representation, which greatly promotes the connectivity of the similarity matrix. We in...