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ISO/IEC 10918-1 : 1993(E)
The Unstuff_0 procedure is shown in Figure D.21. If the new value of B is X'FF', BP is incremented to point to the next
byte and this next B is tested to see if it is zero. If so, B contains a stuffed byte which must be skipped. The zero B is
ignored, and the X'FF' B value which preceded it is inserted in the C-register.
If the value of B after a X'FF' byte is not zero, then a marker has been detected. The marker is interpreted as required and
the entropy-coded segment pointer is adjusted ("Adjust BP" in Figure D.21) so that 0-bytes will be fed to the decoder
until decoding is complete. One way of accomplishing this is to point BP to the byte preceding the marker which follows
the entropy-coded segment.
TISO1210-93/d059
Unstuff_0
BP = BP + 1
Yes
No
C = C OR X'FF00'
Done
Interpret_marker
Adjust BP
B = 0
?
Figure D.21 Unstuff_0 procedure for decoder
Figure D.21 [D59], = 12 cm = 469.%
CCITT Rec. T.81 (1992 E)
75
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