Bitstream
Encyclopedia
A bitstream or bit stream is a time series
of bit
s.
A bytestream is a series of byte
s, typically of 8 bits each, and can be regarded as a special case of a bitstream.
Bitstreams are used extensively in telecommunications and computing
: for example, the SDH communications technology transports synchronous bitstreams, and the TCP
communications protocol
transports a byte stream
without synchronous timing.
or flash memory
chip, although most FPGAs also support a byte-parallel loading method as well. The detailed format of the bitstream for a particular FPGA chip is usually considered proprietary to the FPGA vendor.
In mathematics, several specific infinite sequences of bits have been studied for their mathematical properties; these include the Baum–Sweet sequence
, Ehrenfeucht–Mycielski sequence
, Fibonacci word
, Kolakoski sequence
, regular paperfolding sequence
, Rudin–Shapiro sequence
, and Thue–Morse sequence
.
When a bitstream is captured and stored in a computer storage
medium, a computer file
is created.
Time series
In statistics, signal processing, econometrics and mathematical finance, a time series is a sequence of data points, measured typically at successive times spaced at uniform time intervals. Examples of time series are the daily closing value of the Dow Jones index or the annual flow volume of the...
of bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
s.
A bytestream is a series of byte
Byte
The byte is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer...
s, typically of 8 bits each, and can be regarded as a special case of a bitstream.
Bitstreams are used extensively in telecommunications and computing
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...
: for example, the SDH communications technology transports synchronous bitstreams, and the TCP
Transmission Control Protocol
The Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...
communications protocol
Communications protocol
A communications protocol is a system of digital message formats and rules for exchanging those messages in or between computing systems and in telecommunications...
transports a byte stream
Byte stream
In computer science, a byte stream is a bit stream, in which data bits are grouped into units, called bytes.In computer networking the term octet stream is sometimes used to refer to the same thing; it emphasizes the use of bytes having the length of 8 bits, known as octets.Formally, a byte stream...
without synchronous timing.
Examples
The term bitstream is frequently used to describe the configuration data to be loaded into a field programmable gate array (FPGA). This usage may have originated based on the common method of configuring the FPGA from a serial bit stream, typically from a serial PROMProgrammable read-only memory
A programmable read-only memory or field programmable read-only memory or one-time programmable non-volatile memory is a form of digital memory where the setting of each bit is locked by a fuse or antifuse. Such PROMs are used to store programs permanently...
or flash memory
Flash memory
Flash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It was developed from EEPROM and must be erased in fairly large blocks before these can be rewritten with new data...
chip, although most FPGAs also support a byte-parallel loading method as well. The detailed format of the bitstream for a particular FPGA chip is usually considered proprietary to the FPGA vendor.
In mathematics, several specific infinite sequences of bits have been studied for their mathematical properties; these include the Baum–Sweet sequence
Baum–Sweet sequence
In mathematics the Baum–Sweet sequence is an infinite automatic sequence of 0s and 1s defined by the rule:for n ≥ 0.For example, b4 = 1 because the binary representation of 4 is 100, which only contains one block of consecutive 0s of length 2; whereas b5 = 0 because the binary representation of...
, Ehrenfeucht–Mycielski sequence
Ehrenfeucht–Mycielski sequence
The Ehrenfeucht–Mycielski sequence is a recursively defined sequence of binary digits with pseudorandom properties, defined by .-Definition:The sequence starts with the three bits 010; each successive digit is formed by finding the longest suffix of the sequence that also appears earlier within the...
, Fibonacci word
Fibonacci word
thumb|350px|Characterization by a [[cutting sequence]] with a line of slope 1/\varphi or \varphi-1, with \varphi the [[golden ratio]].A Fibonacci word is a specific sequence of binary digits...
, Kolakoski sequence
Kolakoski sequence
In mathematics, the Kolakoski sequence is an infinite list that begins withThe rules for generating this sequence are as follows: 1) The only numbers allowed are 1 and 2 2) Each number tells us how many numbers to append to the sequence...
, regular paperfolding sequence
Regular paperfolding sequence
In mathematics the regular paperfolding sequence, also known as the dragon curve sequence, is an infinite automatic sequence of 0s and 1s defined as the limit of the following process:...
, Rudin–Shapiro sequence
Rudin–Shapiro sequence
In mathematics the Rudin–Shapiro sequence, also known as the Golay–Rudin–Shapiro sequence is an infinite automatic sequence named after Marcel Golay, Walter Rudin and Harold S. Shapiro, who independently investigated its properties.-Definition:...
, and Thue–Morse sequence
Thue–Morse sequence
In mathematics, the Thue–Morse sequence, or Prouhet–Thue–Morse sequence, is a binary sequence that begins:Any other ordered pair of symbols may be used instead of 0 and 1; the logical structure of the Thue–Morse sequence does not depend on the symbols that are used to represent it.- Direct...
.
When a bitstream is captured and stored in a computer storage
Computer storage
Computer data storage, often called storage or memory, refers to computer components and recording media that retain digital data. Data storage is one of the core functions and fundamental components of computers....
medium, a computer file
Computer file
A computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program and is usually based on some kind of durable storage. A file is durable in the sense that it remains available for programs to use after the current program has finished...
is created.
See also
- MPEG Elementary streamElementary streamAn elementary stream as defined by MPEG communication protocol is usually the output of an audio or video encoder. ES contains only one kind of data, e.g. audio, video or closed caption. An elementary stream is often referred to as "elementary", "data", "audio", or "video" bitstreams or streams...
- Bitstream formatBitstream formatA bitstream format is the format of the data found in some stream of bits used in a digital communication or data storage application. The term typically refers to the format of the output of an encoder or the format of the input to a decoder when using data compression.Standardized...
- Bit stream accessBit stream accessBit-stream access refers to the situation where a wireline incumbent installs a high-speed access link to the customers premises and then makes this access link available to third parties, to enable them to provide high speed services to customers...