ISO/IEC 10918-1 : 1993(E)
3.1.82
lossless:
A descriptive term for encoding and decoding processes and procedures in which the output of the
decoding procedure(s) is identical to the input to the encoding procedure(s).
3.1.83
lossless coding:
The mode of operation which refers to any one of the coding processes defined in this
Specification in which all of the procedures are lossless (see Annex H).
3.1.84
lossy:
A descriptive term for encoding and decoding processes which are not lossless.
3.1.85
marker:
A two-byte code in which the first byte is hexadecimal FF (X'FF') and the second byte is a value
between 1 and hexadecimal FE (X'FE').
3.1.86
marker segment:
A marker and associated set of parameters.
3.1.87
MCU-row:
The smallest sequence of MCU which contains at least one line of samples or one block-row from
every component in the scan.
3.1.88
minimum coded unit; MCU:
The smallest group of data units that is coded.
3.1.89
modes (of operation):
The four main categories of image coding processes defined in this Specification.
3.1.90
more probable symbol; MPS:
For a binary decision, the decision value which has the larger probability.
3.1.91
non-differential frame:
The first frame for any components in a hierarchical encoder or decoder. The
components are encoded or decoded without subtraction from reference components. The term refers also to any frame in
modes other than the hierarchical mode.
3.1.92
non-interleaved:
The descriptive term applied to the data unit processing sequence when the scan has only one
component.
3.1.93
parameters:
Fixed length integers 4, 8 or 16 bits in length, used in the compressed data formats.
3.1.94
point transform:
Scaling of a sample or DCT coefficient.
3.1.95
precision:
Number of bits allocated to a particular sample or DCT coefficient.
3.1.96
predictor:
A linear combination of previously reconstructed values (in lossless mode coding).
3.1.97
probability estimation state machine:
An interlinked table of probability values and indices which is used to
estimate the probability of the LPS (in arithmetic coding).
3.1.98
probability interval:
The probability of a particular sequence of binary decisions within the ordered set of all
possible sequences (in arithmetic coding).
3.1.99
(probability) sub-interval:
A portion of a probability interval allocated to either of the two possible binary
decision values (in arithmetic coding).
3.1.100
procedure:
A set of steps which accomplishes one of the tasks which comprise an encoding or decoding
process.
3.1.101
process:
See coding process.
3.1.102
progressive (coding):
One of the DCT-based processes defined in this Specification in which each scan
typically improves the quality of the reconstructed image.
3.1.103
progressive DCT-based:
The mode of operation which refers to any one of the processes defined in Annex G.
3.1.104
quantization table:
The set of 64 quantization values used to quantize the DCT coefficients.
3.1.105
quantization value:
An integer value used in the quantization procedure.
3.1.106
quantize:
The act of performing the quantization procedure for a DCT coefficient.
3.1.107
reference (reconstructed) component:
Reconstructed component data which is used in a subsequent frame of a
hierarchical encoder or decoder process (in hierarchical mode coding).
CCITT Rec. T.81 (1992 E)
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