v1.0.4

• ArithmeticCoder:

  • Exposed buildContextModel method to allow customization of the context model creation.
  • Renamed _buildModels to _buildContextModelCached and updated to use buildContextModel.
  • Updated decode method to use models.eof symbol dynamically instead of hardcoded 256.

• ContextModel and ContextState:

  • Added support for order-3 context model:
    • Added ContextStateOrder3 with three previous symbols.
    • Added ContextModelOrder3 with a 3D Fenwick tree structure and a shrink factor to reduce memory usage.
  • Added order getter to ContextState and ContextModel to indicate the model order.
  • Added static maxContextOrder constant (value 3) to ContextModel.
  • Updated factory constructor in ContextModel to support order 3.
  • Updated all context state classes to implement order getter.
  • Updated all context model classes to implement order getter.
  • ContextModelOrder3:
    • Uses a 3D list of Fenwicks with size reduction on the 3rd dimension.