In this paper, we propose a new mathematical method that can improve the accuracy of reconstruction luma to be able to choose the correct method of restoration for screen content images (SCIs). After receiving the decoded luma image and subsampled chroma image from the decoder, SSE (the sum of squares due to error) minimization is proposed to identify the used chroma subsampling scheme before compression. By using our method, subsampling reconstructed can be predicted more precisely through our way.
