Brotli format change: improved encoding of Huffman codes

This change removes the redundant HCLEN, HLENINC and HLEN fields from the encoding of the complex Huffman codes and derives these from an invariant of the code length sequence. Based on a patch by Robert Obryk.
2013-12-17 17:17:57 +01:00
parent 30625ba238
commit b89f3be40b
6 changed files with 109 additions and 145 deletions
@@ -87,7 +87,7 @@ void CreateBackwardReferences(size_t num_bytes,
        // If we are not inserting any symbols, inserting one is more
        // expensive than if we were inserting symbols anyways.
        if (insert_length < 1) {
-          cost_diff_lazy += 1.0;
+          cost_diff_lazy += 0.97;
        }
        // Add bias to slightly avoid lazy matching.
        cost_diff_lazy += 2.0 + delayed_backward_references_in_row * 0.2;