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The Cross Component Linear Model (CCLM) is an intra prediction tool for chroma that was adopted in Versatile Video Coding (VVC) standard. It generates an intra-predictor by utilizing the linear correlation existing between the current chroma block and its co-located reconstructed luma region. However, the predictor generated by CCLM can potentially have discontinuity with its adjacent regions since it does not consider the adjacent samples during its predictor generation. So, we propose a new method called CCLM Combined with Decoder-side Intra Mode Derivation (CCDIMD) to overcome this problem. The key idea of CCDIMD is a weighted combination of the predictor generated by CCLM and the predictor generated by an intra-prediction mode inferred using the intra mode derivation process of DIMD. Our proposed method shows BDBR gains respectively of -0.02%, -1.05%, and -0.96% in Y, Cb, and Cr for 4:2:0 color format videos; -0.03%, - 0.34%, and -0.29% in Y, Cb, and Cr for 4:2:2 color format videos; and -0.10%, -0.40%, and -0.53% in Y, Cb, and Cr for 4:4:4 color format videos.
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