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The quantizers to load are numbers between 0 and 7, where 7 indicates highest precision and 1 means lowest precision and zero means no data at all (see quantizer table).

There are 4 different encoding modes to choose from for each channel. The modes 1 and 2 mean different things on the master and the slave channel. Many encoding modes work with the combination of a base table (selected from fixed built-in tables) and some deviation. The final table is obtained by adding the built-in base table and the deltas. The deltas for this are in the range of 0..7, but no wrap-around is performed on overflow, so a base quantizer of 5 and a delta of 3 results in an invalid quantizer of 8. The delta table might be shorter than the base table. In this case, the delta table is expanded before delta application. (Note that mode 1 on the slave channel is not the standard delta/base model and works differently!)

All quantizers are directly encoded as binary numbers

One of four quantizer base tables is selected and a delta list is stored. The first n deltas are stored in full precision (3 bits), all later deltas are stored with only b bits. The b-bit number from the file is added to a base delta c to obtain the later entries in the delta table. The expanded delta table is thenn added to the selected base table, no wraparound.

A delta table like in the other delta modes is used, but it is not expanded before the master channel is added to it. This addition is with wraparound, so a 7 in the delta table is essentially a -1. The resulting quantizer list is then expanded. The bandlets covered by expansion are not related to the master channel. The delta table itself is stored huffman encoded by one of four different Huffman trees.

This mode is like mode 1 on the slave channel a mode where the difference to the master channel is encoded. Only as many codes as are encoded in the difference table are taken from the master channel. After summing the master codes and the deltas, the final result is expanded.

In this case, the differences between the channels are themselves expressed as differences between adjacent elements. The actual difference between the master and the slave quantizer is the sum of all delta-encoded differences seen up and including the quantizer difference for the current quantizer.

A base table and a delta table are combined just like in mode 1 for the master channel, but only the first entry of the delta table is directly encoded. All later entries of the delta table are huffman encoded differences to the previous entry of the delta table. The difference is stored modulo 8 (so a wrapping addition is used), resulting in a delta table containing the numbers 0 to 7. This delta table is then added after expansion to the base table.

This mode is straight-forward and means that the delta table covers the whole amount of bandlets used in this frame.

Deltas are only stored for the first n bandlets (number is given in the bitstream), the delta table is expanded with zeroes (meaning no change to the base table)

Works like mode 1, but instead of zeroes, all non-present deltas are assumed to be one.

For all bandlets not given by the delta table, read a one bit that directly is the delta (zero or one).

This mode expands with a number of ones followed by a number of zeroes. Details will be given soon.

• 2 bit coding mode

• for each coded bandlet
  • 3 bits quantizer

• 2 bit: selection of quantizer base table
• expansion information (see below)
• 5 bit: number of bandlets with full precision delta (n)
• 2 bit: bits of non-full-precision deltas (b)
• 3 bit: base value for non-full-precision deltas (c)
• for each full-precision bandlet
  • 3 bits of delta
• for each reduced-precision bandlet
  • b bits of delta.

• expansion information
• if number of bandlets with delta > 0
  • 2 bit: selection of quantizer delta encoding huffman tree
• for each bandlet with delta:
  • huffman code for delta (gets added to master channel quantizer, wrapping around)
• if expansion mode is 2:
  • for each bandlet covered by expansion: 1 bit direct quantizer data

• expansion information (see below)
• 1 bit: unknown
• 1 bit: selection of quantizer delta encoding huffman tree (Only Trees 0 and 1 are selectable)
• 3 bit: quantizer for lowest bandlets
• 4 bit: quantizer table select
• …

• 2 bit: selection of quantizer base table
• expansion information (see below)
• If number of bandlets with delta > 0
  • 2 bit: selection of quantizer delta encoding huffman tree
  • 3 bit: quantizer for bandlet 0
• for each bandlet with delta
  • huffman code representing delta between previous and this quantizer index
• if slave channel and expansion mode is 2:
  • for each past-delta bandlet: 1 bit delta info (1 or 0)

• 2 bit: expansion mode
  • mode 0: no further data
  • mode 1/2/3: 5 bits: bandlets with deltas
  • mode 3: 2 bits: split point