**ISO/IEC 10918-1 : 1993(E)**

TISO1500-93/d088

NEXTBIT

CNT = 0

?

Yes

No

B = NEXTBYTE

CNT = 8

B = X'FF'

?

Yes

No

B2 = NEXTBYTE

B2 = 0

?

Yes

Yes

No

No

B2 = DNL

?

BIT = SRL B 7

CNT = CNT 1

B = SLL B 1

Process DNL marker

Return BIT

Error

Terminate scan

**Figure F.18 Procedure for fetching the next bit of compressed data**

Figure F.18 [D88] = 17 cm = 665 %

**F.2.3**

**Sequential DCT decoding process with 8-bit precision extended to four sets of Huffman tables**

This process is identical to the Baseline decoding process described in F.2.2, with the exception that the decoder shall be

capable of using up to four DC and four AC Huffman tables within one scan. Four DC and four AC Huffman tables is the

maximum allowed by this Specification.

**F.2.4**

**Sequential DCT decoding process with arithmetic coding**

This subclause describes the sequential DCT decoding process with arithmetic decoding.

The arithmetic decoding procedures for decoding binary decisions, initializing the statistical model, initializing the

decoder, and resynchronizing the decoder are listed in Table D.4 of Annex D.

Some of the procedures in Table D.4 are used in the higher level control structure for scans and restart intervals described

in F.2. At the beginning of scans and restart intervals, the probability estimates used in the arithmetic decoder are reset to

the standard initial value as part of the Initdec procedure which restarts the arithmetic coder.

**CCITT Rec. T.81 (1992 E)**

**111**