2.6.4 Converting Match Length into Length Header and Length Footer Values

The match length is converted into a length header and a length footer. The length header can have one of eight possible values, with a range of [0, 7], indicating a match of length 2, 3, 4, 5, 6, 7, 8, or a length greater than 8. If the match length is 8 or less, there is no length footer. Otherwise, the value of the length footer is equal to the match length minus 9. The following is a pseudocode example of obtaining the length header and footer.

 if match_length <= 8
    length_header ← match_length-2
    length_footer ← null
 else
    length_header ← 7
    length_footer ← match_length-9
 endif

Match length	Length header	Length footer value
2	0	None
3	1	None
4	2	None
5	3	None
6	4	None
7	5	None
8	6	None
9	7	0
10	7	1
…	7	…
n	7	n-9