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29-680: Binary Format for Scenes ( BIFS ) is a binary format for two- or three-dimensional audiovisual content. It is based on VRML and part 11 of the MPEG-4 standard. BIFS is MPEG-4 scene description protocol to compose MPEG-4 objects, describe interaction with MPEG-4 objects and to animate MPEG-4 objects. MPEG-4 Binary Format for Scene (BIFS) is used in Digital Multimedia Broadcasting (DMB). The XMT framework accommodates substantial portions of SMIL , W3C Scalable Vector Graphics (SVG) and X3D (the new name of VRML). Such

58-405: A computer program to interpret the data in the file. The header often contains a signature or magic number which can identify the format. For example, a GIF file can contain multiple images, and headers are used to identify and describe each block of image data. The leading bytes of the header would contain text like GIF87a or GIF89a that can identify the binary as a GIF file. If

87-422: A (probably unintelligible) display of textual characters. If the file is opened in some other application, that application will have its own use for each byte: maybe the application will treat each byte as a number and output a stream of numbers between 0 and 255—or maybe interpret the numbers in the bytes as colors and display the corresponding picture. Other type of viewers (called 'word extractors') simply replace

116-404: A binary file does not contain any headers, it may be called a flat binary file . A text file may consist partly or entirely of encoded binary information. When sending binary files over the network they may be encoded so that they use only printable characters. This is often necessary due to the limitations of network protocols used for internet browsing and e-mail communication. One such encoding

145-463: A binary-to-text encoding comes from a need to communicate arbitrary binary data over preexisting communications protocols that were designed to carry only English language human-readable text. Those communication protocols may only be 7-bit safe (and within that avoid certain ASCII control codes), and may require line breaks at certain maximum intervals, and may not maintain whitespace . Thus, only

174-514: A mechanism for encoding plain text . For example: By using a binary-to-text encoding on messages that are already plain text, then decoding on the other end, one can make such systems appear to be completely transparent . This is sometimes referred to as 'ASCII armoring'. For example, the ViewState component of ASP.NET uses base64 encoding to safely transmit text via HTTP POST, in order to avoid delimiter collision . The table below compares

203-457: A pixel, or even an entire word. Binary itself is meaningless, until such time as an executed algorithm defines what should be done with each bit, byte, word or block. Thus, just examining the binary and attempting to match it against known formats can lead to the wrong conclusion as to what it actually represents. This fact can be used in steganography , where an algorithm interprets a binary data file differently to reveal hidden content. Without

232-481: A public 2048-word dictionary. The 95 isprint codes 32 to 126 are known as the ASCII printable characters . Some older and today uncommon formats include BOO, BTOA , and USR encoding. Most of these encodings generate text containing only a subset of all ASCII printable characters: for example, the base64 encoding generates text that only contains upper case and lower case letters, (A–Z, a–z), numerals (0–9), and

261-414: A representation can be directly played back by a SMIL or VRML player, but can also be binarised to become a native MPEG-4 representation that can be played by an MPEG-4 player. Another bridge has been created with BiM (Binary MPEG format for XML). This computer-storage -related article is a stub . You can help Misplaced Pages by expanding it . Binary file A binary file is a computer file that

290-576: A sequence of bytes , which means the binary digits ( bits ) are grouped in eights. Binary files typically contain bytes that are intended to be interpreted as something other than text characters . Compiled computer programs are typical examples; indeed, compiled applications are sometimes referred to, particularly by programmers, as binaries . But binary files can also mean that they contain images, sounds, compressed versions of other files, etc. – in short, any type of file content whatsoever. Some binary files contain headers , blocks of metadata used by

319-442: Is Base64 . Also, files containing public-key and private-key information for use in systems employing asymmetric cryptography (such as website certificates ) may also be stored with the binary information encoded in printable characters. To send binary files through certain systems (such as email ) that do not allow all data values, they are often translated into a plain text representation (using, for example, Base64 ). Encoding

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348-446: Is encoding of data in plain text . More precisely, it is an encoding of binary data in a sequence of printable characters . These encodings are necessary for transmission of data when the communication channel does not allow binary data (such as email or NNTP ) or is not 8-bit clean . PGP documentation ( RFC   4880 ) uses the term " ASCII armor " for binary-to-text encoding when referring to Base64 . The basic need for

377-435: Is encoded into seven-bit ASCII characters (generally using only alphanumeric and punctuation characters—the ASCII printable characters). Upon safe arrival at its destination, it is then decoded back to its eight-bit form. This process is referred to as binary to text encoding. Many programs perform this conversion to allow for data-transport, such as PGP and GNU Privacy Guard . Binary-to-text encoding methods are also used as

406-426: Is not a text file . The term "binary file" is often used as a term meaning "non-text file". Many binary file formats contain parts that can be interpreted as text; for example, some computer document files containing formatted text , such as older Microsoft Word document files, contain the text of the document but also contain formatting information in binary form. Binary files are usually thought of as being

435-452: Is translated by viewing it as a stream of bits, breaking this stream in chunks of six bits and generating the sequence of corresponding characters. The different encodings differ in the mapping between sequences of bits and characters and in how the resulting text is formatted. Some encodings (the original version of BinHex and the recommended encoding for CipherSaber ) use four bits instead of six, mapping all possible sequences of 4 bits onto

464-531: The Macintosh that are binary compatible, which means that a file produced in a Windows environment is interchangeable with a file produced on a Macintosh. This avoids many of the conversion problems caused by importing and exporting data. One possible binary compatibility issue between different computers is the endianness of the computer. Some computers store the bytes in a file in a different order. Binary-to-text encoding A binary-to-text encoding

493-415: The "+", "/", and "=" symbols. Some of these encoding (quoted-printable and percent encoding) are based on a set of allowed characters and a single escape character . The allowed characters are left unchanged, while all other characters are converted into a string starting with the escape character. This kind of conversion allows the resulting text to be almost readable, in that letters and digits are part of

522-457: The 94 printable ASCII characters are "safe" to use to convey data. The ASCII text-encoding standard uses 7 bits to encode characters. With this it is possible to encode 128 (i.e. 2 ) unique values (0–127) to represent the alphabetic, numeric, and punctuation characters commonly used in English , plus a selection of Control characters which do not represent printable characters. For example,

551-449: The C/C++ "end of line" character (the ASCII linefeed character) and the end-of-line sequence Windows expects in files (the ASCII carriage return and linefeed characters in sequence). In Unix-like systems, the C and C++ standard libraries on those systems also allow the programmer to specify whether a file is expected to be text or binary, but the libraries can and do ignore that parameter, as

580-459: The algorithm, it is impossible to tell that hidden content exists. Two files that are binary compatible will have the same sequence of zeros and ones in the data portion of the file. The file header, however, may be different. The term is used most commonly to state that data files produced by one application are exactly the same as data files produced by another application. For example, some software companies produce applications for Windows and

609-430: The allowed characters, and are therefore left as they are in the encoded text. These encodings produce the shortest plain ASCII output for input that is mostly printable ASCII. Some other encodings ( base64 , uuencoding ) are based on mapping all possible sequences of six bits into different printable characters. Since there are more than 2  = 64 printable characters, this is possible. A given sequence of bytes

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638-701: The capital letter A is represented in 7 bits as 100 0001 2 , 0x41 (101 8 ) , the numeral 2 is 011 0010 2 0x32 (62 8 ), the character } is 111 1101 2 0x7D (175 8 ), and the Control character RETURN is 000 1101 2 0x0D (15 8 ). In contrast, most computers store data in memory organized in eight-bit bytes . Files that contain machine-executable code and non-textual data typically contain all 256 possible eight-bit byte values. Many computer programs came to rely on this distinction between seven-bit text and eight-bit binary data, and would not function properly if non-ASCII characters appeared in data that

667-461: The data has the disadvantage of increasing the file size during the transfer (for example, using Base64 will increase the file's size by approximately 30%), as well as requiring translation back into binary after receipt. The increased size may be countered by lower-level link compression, as the resulting text data will have about as much less entropy as it has increased size, so the actual data transferred in this scenario would likely be very close to

696-467: The end-of-line sequence in Unix-like systems is just the C/C++ end-of-line character. A hex editor or viewer may be used to view file data as a sequence of hexadecimal (or decimal, binary or ASCII character) values for corresponding bytes of a binary file. If a binary file is opened in a text editor , each group of eight bits will typically be translated as a single character, and the user will see

725-406: The file is itself treated as an executable and run, then the operating system will attempt to interpret the file as a series of instructions in its machine language . Standards are very important to binary files. For example, a binary file interpreted by the ASCII character set will result in text being displayed. A custom application can interpret the file differently: a byte may be a sound, or

754-447: The most used forms of binary-to-text encodings. The efficiency listed is the ratio between the number of bits in the input and the number of bits in the encoded output. "A Convention for Human-readable 128-bit Keys". A series of small English words is easier for humans to read, remember, and type in than decimal or other binary-to-text encoding systems. Each 64-bit number is mapped to six short words, of one to four characters each, from

783-419: The size of the original binary data. See Binary-to-text encoding for more on this subject. Microsoft Windows and its standard libraries for the C and C++ programming languages allow the programmer to specify a parameter indicating if a file is expected to be plain text or binary when opening a file; this affects the standard library calls to read and write from the file in that the system converts between

812-484: The unprintable characters with spaces revealing only the human-readable text. This type of view is useful for a quick inspection of a binary file in order to find passwords in games, find hidden text in non-text files and recover corrupted documents. It can even be used to inspect suspicious files (software) for unwanted effects. For example, the user would see any URL/email to which the suspected software may attempt to connect in order to upload unapproved data (to steal). If

841-442: Was expected to include only ASCII text. For example, if the value of the eighth bit is not preserved, the program might interpret a byte value above 127 as a flag telling it to perform some function. It is often desirable, however, to be able to send non-textual data through text-based systems, such as when one might attach an image file to an e-mail message. To accomplish this, the data is encoded in some way, such that eight-bit data

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