Systems, methods, and media are provided for loop filtering across raster scan slices. One example includes obtaining data comprising one or more pictures, including obtaining a first block located in a first slice of one of the pictures. The example then includes determining a second block is located in a second slice of the picture, the second block including one or more pixels for use in performing loop filtering of a pixel of the first block, and determining that loop filtering across slice boundaries is disabled. Based on this disabling, the example determines that the one or more pixels of the second block are unavailable for performing loop filtering of the pixel of the first block, and duplicates at least one pixel of the first block or at least one pixel of an additional block of the first slice for performing loop filtering of the pixel of the first block.