An example device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: apply a downsampling convolutional neural network layer to a first color component of a block of video data, the first color component of the block having a first size, wherein applying the downsampling convolutional neural network layer to the first color component generates a downsampled first color component having a second size smaller than the first size; filter a second color component having the second size to form a filtered second color component; concatenate the downsampled first color component with the filtered second color component to form concatenated color components; and filter the concatenated color components to form a filtered concatenated component including a filtered downsampled first color component.