ZZ(K) = EXTEND(ZZ(K),SSSS)

Figure F.14.

(see F.2.2.3). The values SSSS and R are derived from RS. The value of SSSS is the four low order bits of the composite

value and R contains the value of RRRR (the four high order bits of the composite value). The interpretation of these

values is described in F.1.2.2. EXTEND is shown in Figure F.12.

category. For the AC coefficient this 8-bit value determines the zero run length and non-zero coefficient category.

of DECODE makes use of the ordering of the Huffman codes in HUFFCODE according to both value and code size.

Many other implementations of DECODE are possible.

to decode a pointer to the HUFFVAL table. MINCODE, MAXCODE and VALPTR each have 16 entries, one for each

possible code size. MINCODE(I) contains the smallest code value for a given length I, MAXCODE(I) contains the largest

code value for a given length I, and VALPTR(I) contains the index to the start of the list of values in HUFFVAL which

are decoded by code words of length I. The values in MINCODE and MAXCODE are signed 16-bit integers; therefore, a

value of 1 sets all of the bits.

Note that the 8-bit "VALUE" is returned to the procedure which invokes DECODE.