3.1.8.1.6 Linearization

The quantized tile components are linearized by raster scanning each of the sub-bands. The sub-band coefficient scan and traversal order is illustrated in the following figure.

Raster scan of sub-band coefficients

Figure 9: Raster scan of sub-band coefficients

Linearization of the sub-bands is conducted in the following sequence: HL1, LH1, HH1, HL2, LH2, HH2, HL3, LH3, HH3, and LL3, as shown in the following figure.

Sub-band traversal order

Figure 10: Sub-band traversal order

The coefficients from LL3 also undergo differential encoding. Except for the first coefficient, every raster-scanned LL3 coefficient is subtracted from its previous neighbor. For example, if the raster-scanned LL3 coefficients are

 [64, 32, 42, 54, 50, 60, 40, 70]

Then, after differential encoding, they would get converted to

 [64, -32, 10, 12, -4, 10, -20, 30]