A method for video processing is provided. The method includes determining, for a conversion between a current video block of a video that is a chroma block and a coded representation of the video, whether to derive maximum values and/or minimum values of a luma component and a chroma component that are used to derive parameters of a cross-component linear model (CCLM) based on availability of a left-neighboring block and an above-neighboring block of the current video block; and performing the conversion based on the determining.