Bink Video version b

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Bink is a video codec that uses Vector Quantization along with DCT and Motion Compensation). This version of codec was used in Heroes of Might and Magic III. The video is packaged in custom Bink files.

Each plane is coded separately. The Y plane is always coded first in each frame.

It differs from its successor used in versions 'f'-'i' (at least) in some details.

Decoding

Bundles

Bundle size lengths are always 13 bits while newer codec calculates size lengths from plane width. Also bundle data is stored in plain with known number of bits per entry, no Huffman coding is employed.

bundle type bits signed comments
block type 4 no
colours 8 no
pattern 8 no pattern value for each line of pattern block fill (type 6)
? 5 yes probably X motion vector component
? 5 yes probably Y motion vector component
intra block DC 11 no
inter block DC 11 yes
intra quant? 4 no presumably quantizer for intra block
inter quant? 4 no presumably quantizer for inter block
? 7 no used in residue block (type 3), might be number of residue coefficients coded


Block types

0 - skip block?

not sure whether it exists at all

1 - pattern run block

 4 bits - scan type

The rest is coded like bit, length. colour(s). length is coded as 0-6 bits depending on number of elements left not filled yet. Depending on bit value that part of block (mind the scan pattern though) is either filled with single colour or with many colours read from bundle.

2 - intra DCT?

looks like this one uses floating-point DCT

3 - residue block?

4 - inter DCT?

5 - fill block

6 - pattern fill

It's standard 2-colour fill.

7 - motion block?

8 - raw fill block