Function decode_tile 

pub fn decode_tile(
    data: &[u8],
    opts: LjpegOptions,
    dst: &mut [u16],
    dst_stride: usize,
    tile_row_len: usize,
    clip_w: usize,
    clip_h: usize,
) -> Result<LjpegHeader>

Decode a lossless JPEG tile into a destination buffer.

The decoded sample stream fills a virtual tile whose rows are tile_row_len samples long (JPEG rows need not match tile rows: DNG commonly encodes a W-pixel tile row as a W/2 x 2-component JPEG row, and some encoders put two tile rows in one JPEG row). Only samples with column < clip_w and row < clip_h are written, at dst[row * dst_stride + col] — this clips tiles that overhang the image edge.