inflate-huffman ( bitstream tables -- bytes )

Vocabulary

compression.inflate.private

Inputs

bitstream	an object
tables	an object

Outputs

bytes

an object

Definition

USING: arrays bitstreams compression.huffman kernel math
sequences ;

IN: compression.inflate.private

:: inflate-huffman ( bitstream tables -- bytes )
    bitstream tables [ <huffman-decoder> ] with map :> tables [
        tables first read1-huff2 dup 256 > [
            dup 285 = [
                dup 264 > [
                    dup 261 - 4 /i dup 5 >
                    [ bad-zlib-data ] when bitstream read 2array
                ] when
            ] unless tables second read1-huff2 dup 3 > [
                dup 2 - 2 /i dup 13 > [ bad-zlib-data ] when
                bitstream read 2array
            ] when 2array
        ] when dup 256 = not
    ] [ ] produce nip [
        dup array? [
            first2 [
                dup array? [ first2 ] [ 0 ] if
                [ 257 - length-table nth ] [ + ] bi*
            ] [
                dup array? [ first2 ] [ 0 ] if
                [ dist-table nth ] [ + ] bi*
            ] bi* 2array
        ] when
    ] map ;