===== Quantization precision difference encoding trees =====
values encoded as three-bit signed values, so the negative values get codes after the positive values. The trees are built as [[canonical huffman trees]]

==== Tree 0 ====
  * -1: 2 bit
  * 0: 1 bit
  * +1: 2 bit

==== Tree 1 ====
  * -2: 3 bit
  * -1: 3 bit
  * 0: 1 bit
  * +1: 3 bit
  * +2: 3 bit

==== Tree 2 ====
  * -4: 5 bit
  * -3: 4 bit
  * -2: 4 bit
  * -1: 3 bit
  * 0: 1 bit
  * +1: 3 bit
  * +2: 4 bit
  * +3: 5 bit

==== Tree 3 ====
  * -4: 5 bit
  * -3: 5 bit
  * -2: 4 bit
  * -1: 3 bit
  * 0: 1 bit
  * +1: 3 bit
  * +2: 4 bit
  * +3: 4 bit