Multi-kernel retrieval of land surface bidirectional reflectance distribution functions based on l1-norm optimization

The existing kernel-based methods for retrieving land surface bidirectional reflectance distribution functions (BRDFs) usually use a pre-determined combination of kernels and it is fixed for an entire image, which is unable to accommodate the different characteristics from various land cover types. In this study, a multi-kernel method based on l
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-norm optimization is proposed. This method is able to automatically select appropriate kernels for each pixel from a kernel dictionary that contains several commonly used kernels. Experimental results show that BRDF retrieval accuracy is improved by adopting this new method.