Parallel box filtering through reuse of existing circular filter

A sample filtering system and method for concurrently filtering sample data for two or more sequential pixels (in a scan-line) are disclosed. The system may include a sample cache, a control register, a read cache controller, and a sample-to-pixel calculation unit. The read cache controller reads a first set of S samples from the sample cache, and outputs a second set of S samples to the sample-to-pixel calculation unit. The second set of samples may have one or more subsets of samples, with each subset of samples selected to cover the filter region for one of the sequential pixels. The sample-to-pixel calculation unit may process each subset separately and concurrently.