Function imagefmt::png::read_chunks

pub fn read_chunks<R, T>(
    reader: &mut R, 
    req_fmt: ColFmt, 
    chunk_names: &[[u8; 4]]
) -> Result<(Image<T>, Vec<ExtChunk>)> where
    R: Read + Seek,
    T: Sample,
    Buffer: ToVec<T>, 

Like png::read but also returns the requested extension chunks.

If the requested chunks are not present they are ignored.