| podobné slovo | definícia |
encoding
(mass) | encoding
- kódovanie, kódovacia stránka |
coding dna
(encz) | coding DNA, n: |
coding system
(encz) | coding system, n: |
decoding
(encz) | decoding,dekódování n: Zdeněk Brož |
encoding
(encz) | encoding,kódování n: |
encodings
(encz) | encodings,kódování n: pl. Michal Božoň |
microcoding
(encz) | microcoding,mikrokódování n: Zdeněk Brož |
recoding
(encz) | recoding, |
coding dna
(wn) | coding DNA
n 1: sequence of a gene's DNA that transcribes into protein
structures; "exons are interspersed with introns" [syn:
exon, coding DNA] [ant: intron, noncoding DNA] |
coding system
(wn) | coding system
n 1: a system of signals used to represent letters or numbers in
transmitting messages |
decoding
(wn) | decoding
n 1: the activity of making clear or converting from code into
plain text; "a secret key or password is required for
decryption" [syn: decoding, decryption, decipherment] |
encoding
(wn) | encoding
n 1: the activity of converting data or information into code
[syn: encoding, encryption] |
noncoding dna
(wn) | noncoding DNA
n 1: sequence of a eukaryotic gene's DNA that is not translated
into a protein [syn: intron, noncoding DNA] [ant:
coding DNA, exon] |
recoding
(wn) | recoding
n 1: converting from one code to another |
adaptive transform acoustic coding
(foldoc) | Adaptive TRansform Acoustic Coding
ATRAC
(ATRAC) An audio compression algorithm,
introduced by Sony for its Mini Disk, which relies on the
masking of low-amplitude frequency components by temporaly
adjacent high-amplitude components. ATRAC consists of a
three-band subband encoder (0...5.5, 5.5...11, 11...22 kHz)
and a MDCT based transformation encoder.
[Does Sony Minidisk use ADPCM?]
(2001-12-13)
|
advanced audio coding
(foldoc) | Advanced Audio Coding
AAC
(AAC) A successor to MP3, allowing lower bit rates
and more stable quality.
See MPEG-2 AAC Low Profile and MPEG-4 AAC Main Profile.
(2001-12-02)
|
advanced video coding
(foldoc) | H.264
Advanced Video Coding
AVC
(Or Advanced Video Coding, AVC) A low {bit
rate} visual communication standard used in {video
conferencing}. H.264 was developed by MPEG and ITU-T
VCEG to replace H.263.
{Video and image compression resources and research
(http://www.vcodex.fsnet.co.uk/h264.html)}.
(2007-03-16)
|
basic encoding rules
(foldoc) | Basic Encoding Rules
ISO 8825
ITU X.209
X.209
(BER) ASN.1 encoding rules for
producing self-identifying and self-delimiting {transfer
syntax} for data structures described in ASN.1 notations.
BER is an self-identifying and self-delimiting encoding
scheme, which means that each data value can be identified,
extracted and decoded individually.
Huw Rogers once described BER as "a triumph of bloated theory
over clean implementation". He also criticises it as designed
around bitstreams with arbitrary boundaries between data which
can only be determined at a high level.
Documents: ITU-T X.690, ISO 8825-1.
See also CER, DER, PER.
(1998-05-28)
|
boeing airplane company algebraic interpreter coding
(foldoc) | Boeing Airplane Company Algebraic Interpreter Coding
BACAIC
(BACAIC) A pre-Fortran system on the IBM 701
and IBM 650.
(1995-02-08)
|
canonical encoding rules
(foldoc) | Canonical Encoding Rules
CER
(CER) A restricted variant of BER for
producing unequivocal transfer syntax for data structures
described by ASN.1.
Whereas BER gives choices as to how data values may be
encoded, CER and DER select just one encoding from those
allowed by the basic encoding rules, eliminating all of the
options. They are useful when the encodings must be
preserved, e.g. in security exchanges.
CER and DER differ in the set of restrictions that they
place on the encoder. The basic difference between CER and
DER is that DER uses definitive length form and CER uses
indefinite length form.
Documents: ITU-T X.690, ISO 8825-1.
See also PER.
(1998-05-19)
|
character encoding
(foldoc) | character encoding
character encoding scheme
(Or "character encoding scheme") A mapping between
binary data values and character code positions (or "code
points").
Early systems stored characters in a variety of ways,
e.g. four six-bit characters in a 24-bit word, but around
1960, eight-bit bytes started to become the most common data
storage layout, with each character stored in one byte,
typically in the ASCII character set.
In the case of ASCII, the character encoding is an
identity mapping: code position 65 maps to the byte value
65. This is possible because ASCII uses only code positions
representable as single bytes, i.e., values between 0 and
255. (US-ASCII only uses values 0 to 127, in fact.)
From the late 1990s, there was increased use of larger
character sets such as Unicode and many CJK {coded
character sets}. These can represent characters from many
languages and more symbols.
Unicode uses many more than the 256 code positions that can
be represented by one byte. It thus requires more complex
mappings: sometimes the characters are mapped onto pairs of
bytes (see DBCS). In many cases, this breaks programs that
assume a one-to-one mapping of bytes to characters, and so,
for example, treat any occurrance of the byte value 13 as a
carriage return. To avoid this problem, character encodings
such as UTF-8 were devised.
(2015-11-29)
|
character encoding scheme
(foldoc) | character encoding
character encoding scheme
(Or "character encoding scheme") A mapping between
binary data values and character code positions (or "code
points").
Early systems stored characters in a variety of ways,
e.g. four six-bit characters in a 24-bit word, but around
1960, eight-bit bytes started to become the most common data
storage layout, with each character stored in one byte,
typically in the ASCII character set.
In the case of ASCII, the character encoding is an
identity mapping: code position 65 maps to the byte value
65. This is possible because ASCII uses only code positions
representable as single bytes, i.e., values between 0 and
255. (US-ASCII only uses values 0 to 127, in fact.)
From the late 1990s, there was increased use of larger
character sets such as Unicode and many CJK {coded
character sets}. These can represent characters from many
languages and more symbols.
Unicode uses many more than the 256 code positions that can
be represented by one byte. It thus requires more complex
mappings: sometimes the characters are mapped onto pairs of
bytes (see DBCS). In many cases, this breaks programs that
assume a one-to-one mapping of bytes to characters, and so,
for example, treat any occurrance of the byte value 13 as a
carriage return. To avoid this problem, character encodings
such as UTF-8 were devised.
(2015-11-29)
|
clone-and-hack coding
(foldoc) | case and paste
clone-and-hack coding
(From "cut and paste") The addition of a new
feature to an existing system by selecting the code from an
existing feature and pasting it in with minor changes. This
usually results in gross violation of the fundamental
programming tenet, Don't Repeat Yourself.
Common in telephony circles because most operations in a
telephone switch are selected using "case" statements. Leads
to software bloat.
In some circles of Emacs users this is called "programming
by Meta-W", because Meta-W is the Emacs command for copying a
block of text to a kill buffer in preparation to pasting it
in elsewhere. The term is condescending, implying that the
programmer is acting mindlessly rather than thinking carefully
about what is required to integrate the code for two similar
cases.
At DEC, this is sometimes called "clone-and-hack" coding.
[Jargon File]
(1996-03-01)
|
distinguished encoding rules
(foldoc) | Distinguished Encoding Rules
DER
(DER) An X.690 encoding format (or
transfer syntax) for data structures described by ASN.1
that specifies exactly one way to encode a value thus ensuring
a unique, canonical, serialised representation. DER is a
restricted variant of BER. For example, DER has exactly one
way to encode a Boolean value. DER is used in
cryptography, e.g. for digital certificates such as
X.509.
(2016-05-05)
|
hash coding
(foldoc) | hash coding
hash bucket
hashing
hash table
(Or "hashing") A scheme for providing
rapid access to data items which are distinguished by some
key. Each data item to be stored is associated with a key,
e.g. the name of a person. A hash function is applied to
the item's key and the resulting hash value is used as an
index to select one of a number of "hash buckets" in a hash
table. The table contains pointers to the original items.
If, when adding a new item, the hash table already has an
entry at the indicated location then that entry's key must be
compared with the given key to see if it is the same. If two
items' keys hash to the same value (a "hash collision") then
some alternative location is used (e.g. the next free location
cyclically following the indicated one). For best
performance, the table size and hash function must be
tailored to the number of entries and range of keys to be
used. The hash function usually depends on the table size so
if the table needs to be enlarged it must usually be
completely rebuilt.
When you look up a name in the phone book (for example), you
typically hash it by extracting its first letter; the hash
buckets are the alphabetically ordered letter sections.
See also: btree, checksum, CRC, pseudorandom number,
random, random number, soundex.
(1997-08-03)
|
horizontal encoding
(foldoc) | horizontal encoding
An instruction set where each field (a bit or
group of bits) in an instruction word controls some
functional unit or gate directly, as opposed to {vertical
encoding} where instruction fields are decoded (by
hard-wired logic or microcode) to produce the control
signals. Horizontal encoding allows all possible combinations
of control signals (and therefore operations) to be expressed
as instructions whereas vertical encoding uses a shorter
instruction word but can only encode those combinations of
operations built into the decoding logic.
An instruction set may use a mixture of horizontal and
vertical encoding within each instruction. Because an
architecture using horizontal encoding typically requires more
instruction word bits it is sometimes known as a {very long
instruction word} (VLIW) architecture.
(1995-04-23)
|
huffman coding
(foldoc) | Huffman coding
Huffman
Huffman code
Huffman encoding
A data compression technique which varies the
length of the encoded symbol in proportion to its information
content, that is the more often a symbol or token is used, the
shorter the binary string used to represent it in the
compressed stream. Huffman codes can be properly decoded
because they obey the prefix property, which means that no
code can be a prefix of another code, and so the complete set
of codes can be represented as a binary tree, known as a
Huffman tree. Huffman coding was first described in a seminal
paper by D.A. Huffman in 1952.
(1994-12-23)
|
huffman encoding
(foldoc) | Huffman coding
Huffman
Huffman code
Huffman encoding
A data compression technique which varies the
length of the encoded symbol in proportion to its information
content, that is the more often a symbol or token is used, the
shorter the binary string used to represent it in the
compressed stream. Huffman codes can be properly decoded
because they obey the prefix property, which means that no
code can be a prefix of another code, and so the complete set
of codes can be represented as a binary tree, known as a
Huffman tree. Huffman coding was first described in a seminal
paper by D.A. Huffman in 1952.
(1994-12-23)
|
manchester encoding
(foldoc) | Manchester encoding
A method of transmitting bits which
enables the receiver to easily synchronise with the sender.
A simple way of signalling bits might be to transmit a high
voltage for some period for a 1-bit and a low voltage for a 0
bit:
Bits Sent: 1 1 0 0
Signal: High ___________
Low |___________
Time: -> . . . . .
However, when several identical bits are sent in succession,
this provides no information to the receiver about when each
bit starts and stops.
Manchester encoding splits each bit period into two, and
ensures that there is always a transition between the signal
levels in the middle of each bit. This allows the receiver to
synchronise with the sender.
In normal Manchester encoding, a 1-bit is transmitted with a
high voltage in the first period, and a low voltage in the
second, and vice verse for the 0 bit:
Bits Sent: 1 1 0 0
Signal: High __ __ __ __
Low |__| |_____| |__|
Time: -> . ' . ' . ' . ' .
In Differential Manchester encoding, a 1-bit is indicated by
making the first half of the signal equal to the last half of
the previous bit's signal and a 0-bit is indicated by making
the first half of the signal opposite to the last half of the
previous bit's signal. That is, a zero bit is indicated by a
transition at the beginning of the bit.
Like normal Manchester encoding, there is always a transition
in the middle of the transmission of the bit.
Differential Manchester Encoding
Bits Sent: 1 1 0 0
Signal: High ____ __ __ __
Low |_____| |__| |__|
Time: -> . ' . ' . ' . ' .
With each bit period half as long, twice as much bandwidth
is required when using either of the Manchester encoding
schemes.
(1995-11-23)
|
mpeg-4 advanced audio coding scalable sampling rate
(foldoc) | MPEG-4 Advanced Audio Coding Scalable Sampling Rate
MPEG-4 AAC SSR
(MPEG-4 AAC SSR) An AAC
flavour supporting different qualities for different targets.
One stream can contain up to 3 streams for 11.025 kHz (Stream
1), 22.05 (Stream 1 and 2) and 44.1 kHz (all 3 Streams)
sampling frequency. Quality is between Low Profile and Main
profile. See also JPEG-2000.
(2001-12-09)
|
multimedia and hypermedia information coding expert group
(foldoc) | Multimedia and Hypermedia information coding Expert Group
MHEG
(MHEG) is an ISO standard encoding
for multimedia and hypermedia information, designed to
facilitate use and interchange of such information in varied
domains such as games, electronic publishing and medical
applications.
MHEG Home (http://mheg.org/).
(2002-12-30)
|
packed encoding rules
(foldoc) | Packed Encoding Rules
(PER) ASN.1 encoding rules for
producing a compact transfer syntax for data structures
described in ASN.1, defined in 1994.
PER provides a much more compact encoding then BER. It
tries to represents the data units using the minimum number of
bits. The compactness requires that the decoder knows the
complete abstract syntax of the data structure to be
decoded, however.
Documents: ITU-T X.691, ISO 8825-2.
(1998-05-19)
|
perceptional adaptive subband coding
(foldoc) | Perceptional Adaptive Subband Coding
PASC
(PASC) A version of MPEG-1 Layer 1 used
for the Philips Digital Compact Cassette DCC.
(2001-12-13)
|
progressive coding
(foldoc) | progressive coding
interlace
interlaced image
non-interlaced
(Or "interlacing") An
aspect of a graphics storage format or transmission
algorithm that treats bitmap image data non-sequentially
in such a way that later data adds progressively greater
resolution to an already full-size image. This contrasts
with sequential coding.
Progressive coding is useful when an image is being sent
across a slow communications channel, such as the Internet,
as the low-resolution image may be sufficient to allow the
user to decide not to wait for the rest of the file to be
received.
In an interlaced GIF89 image, the pixels in a row are
stored sequentially but the rows are stored in interlaced
order, e.g. 0, 8, 4, 12, 2, 6, 8, 10, 14, 1, 3, 5, 7, 9, 11,
13, 15. Each vertical scan adds rows in the middle of the
gaps left by the previous one.
PNG interlaces both horizontally and vertically using the
"Adam7" method, a seven pass process named after Adam
M. Costello.
Interlacing is also supported by other formats. JPEG
supports a functionally similar concept known as {Progressive
JPEG}. [How does the algorithm differ?]
JBIG uses progressive coding.
See also progressive/sequential coding.
["Progressive Bi-level Image Compression, Revision 4.1",
ISO/IEC JTC1/SC2/WG9, CD 11544, 1991-09-16].
(2000-09-12)
|
progressive/sequential coding
(foldoc) | progressive/sequential coding
The kind of image compression
algorithm used in JBIG where an image coded using
progressive coding can be decoded sequentially, and vice
versa.
(1995-03-01)
|
run-length encoding
(foldoc) | run-length encoding
RLE
A kind of compression algorithm which replaces sequences
("runs") of consecutive repeated characters (or other units of
data) with a single character and the length of the run. This
can either be applied to all input characters, including runs
of length one, or a special character can be used to introduce
a run-length encoded group. The longer and more frequent the
runs are, the greater the compression that will be achieved.
This technique is particularly useful for encoding black and
white images where the data units would be single bit
pixels.
(1994-10-27)
|
sequential coding
(foldoc) | sequential coding
The usual bitmap image
data storage format or transmission algorithm where the
resoluton is constant and later data adds only more area.
This contrasts with progressive coding.
(2000-09-12)
|
speedcoding
(foldoc) | Speedcoding
A pseudocode interpreter for mathematics on
IBM 701 and IBM 650 written by John Backus in 1953.
[Sammet 1969, p. 130].
(2000-03-27)
|
speedcoding 3
(foldoc) | Speedcoding 3
[Listed in CACM 2(5):16, May 1959].
(2000-03-27)
|
storage allocation and coding program
(foldoc) | Storage Allocation and Coding Program
(STAC) A symbolic macro-assembler for the
English Electric DEUCE.
["DEUCE STAC Programming Manual", DEUCE News No. 38, Report
K/AA y 1 DEUCE Library Service, Data Processing and COntrol
Systems DIvision, English Electric Company, Kidsgrove, June].
(1998-06-08)
|
subband encoding
(foldoc) | subband encoding
An audio compression technique where the sound is split into
frequency bands and then parts of the signal which the ear
cannot detect are removed, e.g. a quiet sound masked by a loud
one. The remaining signal is encoded using variable bit-rates
with more bits per sample being used in the mid frequency
range.
Subband encoding is used in MPEG-1.
(1994-11-02)
|
text encoding initiative
(foldoc) | Text Encoding Initiative
(TEI) A project working to establish
a standard for interchanging electronic text for scholarly
research. The TEI has adopted SGML and implemented the TEI
standard as an SGML Document Type Definition.
The TEI was incorporated as a not-for-profit consortium in
December 2000, with host sites in Bergen, Oxford, Virginia,
and Providence RI, USA.
(http://tei-c.org/).
See also Corpus Processing.
[Any connection with Computational Linguistics or {Natural
Language Processing}?]
(2001-03-23)
|
transparent audio coding
(foldoc) | transparent audio coding
A lossy audio compression algorithm
is transparent if the original and decoded signal are
indistinguishable to the human ear. The bit rate depends on
the codec and the audio material. Some codecs (e.g. AAC,
MP3) are optimized for transparent coding at a low data
rate, others (e.g. VQF, MP3Pro, AAC+SBR, WMA) for
distinguisable but pleasant reproduction at lower bit rates.
Typical data rates in kbps for different codecs are:
MP1 288-320
MP2 224-256
MP3 160-224
MPEG-2 AAC 128-160
MPEG-4 AAC 112-144
MPEGplus 160-200
(2001-12-23)
|
vertical encoding
(foldoc) | vertical encoding
An instruction set where a field (a bit or group
of bits) of the instruction word is decoded (either by
hard-wired logic or microcode) to generate signals to
control the functional units, as opposed to {horizontal
encoding} where the instruction word bits are used as the
control signals directly.
With vertical encoding, which combinations of signals and
operations are possible is dictated by the decoding logic; the
instruction field can only select one of these preprogrammed
combinations. This has the advantage that many control
signals can be generated based on only a few instruction word
bits and only valid combinations of control signals can be
generated, e.g. only one source driving a bus at once. An
instruction set may use a mixture of horizontal and vertical
encoding within each instruction.
(1995-04-23)
|
vocoding
(foldoc) | vocoder
vocoding
Hardware or software which implements a
compression algorithm particular to voice.
For example Qualcomm uses a vocoding algorithm to compresses
voice data in digital communication systems such as wireless
CDMA and Eudora voice attach.
(1998-04-29)
|
clone-and-hack coding
(jargon) | clone-and-hack coding
n.
[DEC] Syn. case and paste.
|