===== Level difference encoding Huffman trees =====

There are two sets of trees. The 6-bit-trees and the 4-bit-trees. The four-bit trees encode values betwenn -7 and 7 in 4-bit-twos-complement representation (so 0..7 and 9..15), while the 6 bit trees store values between 0 and 63 and are used modulo 64 in most contexts anyway, so signed/unsigned doesn't matter. These trees are built as [[canonical huffman trees]] from the given length tables.

==== 6-bit trees ====
=== Tree 0 ===
  * 0: 2 Bit
  * 1: 3 Bit
  * 2: 4 Bit
  * 3-6: 8 Bit
  * 7-56: 9 Bit
  * 57-59: 8 Bit
  * 60: 4 Bit
  * 61-63: 3 Bit

=== Tree 1 ===
  * 0: 2 Bit
  * 1-2: 3 Bit
  * 3: 4 Bit
  * 4-6: 8 Bit
  * 7-56: 9 Bit
  * 57-60: 8 Bit
  * 61: 4 Bit
  * 62-63: 3 Bit

=== Tree 2 ===
  * 0: 1 Bit
  * 1: 3 Bit
  * 2-3: 5 Bit
  * 4: 7 Bit
  * 5-58: 9 Bit
  * 59: 8 Bit
  * 60: 7 Bit
  * 61-62: 5 Bit
  * 63: 3 Bit

=== Tree 3 ===
  * 0: 2 Bit
  * 1-2: 3 Bit
  * 3-4: 5 Bit
  * 5: 7 Bit
  * 6-57: 9 Bit
  * 58-59: 7 Bit
  * 60-61: 5 Bit
  * 62-63: 3 Bit

==== 4-bit trees ====
=== Tree 0 ===
  * 0: 2 Bit
  * 1: 3 Bit
  * 2: 4 Bit
  * 3-7: 6 Bit
  * 9-11: 6 Bit
  * 12: 4 Bit
  * 13-15: 3 Bit

=== Tree 1 ===
  * 0: 2 Bit
  * 1-2: 3 Bit
  * 3: 4 Bit
  * 4-7: 6 Bit
  * 9-12: 6 Bit
  * 13: 4 Bit
  * 14-15: 3 Bit

=== Tree 2 ===
  * 0: 1 Bit
  * 1: 3 Bit
  * 2: 4 Bit
  * 3: 5 Bit
  * 4-7: 7 Bit
  * 9-12: 7 Bit
  * 13: 5 Bit
  * 14: 4 Bit
  * 15: 3 Bit

=== Tree 3 ===
  * 0: 2 Bit
  * 1-2: 3 Bit
  * 3: 4 Bit
  * 4: 5 Bit
  * 5: 6 Bit
  * 6-7: 7 Bit
  * 9-10: 7 Bit
  * 11: 6 Bit
  * 12: 5 Bit
  * 13: 4 Bit
  * 14-15: 3 Bit