Sound file format, common digital audio format

When digital sound is stored and processed in a computer, its data must be organized in the form of files, and the file format chosen must be supported by the operating system and application software. Sound file formats used in different computer-level applications are not the same.

Common digital audio formats

	Audio format	Description
1	Wave (. WAV)	Microsoft developed a sound file format, also known as a waveform sound file, is the earliest digital audio format, widely supported by the Windows platform and its applications. WAV format supports a number of compression algorithms, support a variety of audio bits, sampling frequency and channel, using 44.1kHz sampling frequency, 16-bit quantization bit, as with CD, storage space is too large for communication and communication.
2	Module (. MOD)	The format of the file to store the music and music used in a variety of sound samples, with a return on the effect is obvious, the type of unlimited tones and other advantages.
3	MPEG (. MP3)	The MP3 full name is MPEG-1 Audio Layer 3, which was incorporated into the MPEG specification in 1992. The MP3 is capable of compressing digital audio files with high sound quality and low sample rate. In other words, audio files (mostly large files, such as WAV files) can compress files to a lesser extent in the case of a very small loss of sound quality (the human ear simply cannot perceive the loss of this quality).
4	RealAudio (. RA)	Introduced by Real Networks a file format, the biggest feature is the real-time transmission of audio information, especially in the slow speed of the situation, can still be relatively smooth transmission of data, so RealAudio is mainly applicable to online playback on the network. Now the RealAudio file format mainly includes RA (RealAudio), RM (Realmedia,realaudio G2), RMX (RealAudio Secured) and other three kinds, The common purpose of these files is to change the quality of the sound as the bandwidth of the network changes, ensuring that most people hear a smooth sound, so that the audience with more bandwidth has better sound quality.
5	MIDI (. Mid/. RMI)	MIDI is the abbreviation of musical Instrument Digital Interface, also known as musical instrument number interface, is a unified international standard of digital music/electronic synthetic instruments. It defines the way that computer music programs, digital synthesizers and other electronic devices exchange music signals, and provides a protocol for data transmission between electronic musical instruments and computer-connected cables and hardware and devices in different manufacturers, which can simulate the sound of multiple instruments. MIDI files are files in MIDI format, and some instructions are stored in MIDI files. Send these instructions to the sound card, which is synthesized by the sound card according to the instructions.
6	Voice (. VOC)	This kind of file is often encountered in DOS programs and games, it is a digital sound file produced with the Sound Blaster card, similar to the structure of the WAV file, and can be easily converted to each other by some tool software.
7	Sound (. SND)	The sound file is a digital audio file format introduced by Next computer, which supports compression.
8	Audio (. AU)	Multimedia sounds on the Internet primarily use this kind of file. The AU file is a digital sound file under the Unix operating system, and since the Web server on the Internet was primarily Unix-based, this file became the only standard sound file used on the www.
9	AIFF (. AIF)	Apple has developed a sound file format that is supported by Macintosh platforms and applications.
10	CMF (. CMF)	Creative Company's dedicated music format, similar to MIDI, timbre, effects have some features, specifically for the FM sound card, but its compatibility is poor.
11	Cda	Everybody is familiar with the CD this kind of music format, the extension CDA, its sampling frequency is 44.1khz,16 bit quantization bit, like WAV, but the CD storage uses the form of the audio track, also called "Redbook" format, recorded is the waveform stream, is an approximate lossless format.
12	Wma	WMA (Windows Media audio) is Microsoft's masterpiece in the field of Internet audio and video. The WMA format is a way to reduce data traffic but maintain sound quality to achieve a higher compression rate, the compression rate can generally reach 1:18. In addition, WMA can also be used to prevent copying through the DRM (Digital rights Management) scheme, or limit the playing time and the number of plays, or even the limit of the playback machine, can effectively prevent piracy.
13	SACD	It was officially released by Sony Corporation. It has a sample rate of 64 times times the CD format, which is 2.8224MHz. The SACD replay frequency bandwidth of 100kHz, 5 times times the CD format, 24-bit quantization bits, far more than the CD, the sound details are richer and clearer.

Sound file format, common digital audio format