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Convert MP4 to AU

MP4 to AU Conversion Software converts MP4 files to AU quickly and easily. The converter supports common codecs for AU file including ITU-T G.721 4-bit ADPCM, CCITT a-Law (8-bit), PCM 64-bit Float, PCM 32-bit Float, ITU-T G.723 3-bit ADPCM, PCM 32-bit, PCM 16-bit, PCM 8-bit, and so on.

MP4 to AU Conversion Software is very easy to use and supports batch conversion. It is full compatible with both 32-bit and 64-bit editions Windows 10/8/7/Vista/XP/2000.

MP4 to AU Conversion Software is compatible with Windows 10/8/7/Vista/XP/2008/2003/2000

What is MP4?
MPEG-4 Part 14, formally ISO/IEC 14496-14:2003, is a multimedia container format standard specified as a part of MPEG-4. It is most commonly used to store digital audio and digital video streams, especially those defined by MPEG, but can also be used to store other data such as subtitles and still images. Like most modern container formats, MPEG-4 Part 14 allows streaming over the Internet. The official filename extension for MPEG-4 Part 14 files is .mp4, thus the container format is often referred to simply as MP4.

MPEG-4 is a patented collection of methods defining compression of audio and visual (AV) digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG) (ISO/IEC JTC1/SC29/WG11) under the formal standard ISO/IEC 14496 - Coding of audio-visual objects. Uses of MPEG-4 include compression of AV data for web (streaming media) and CD distribution, voice (telephone, videophone) and broadcast television applications.

MPEG-4 absorbs many of the features of MPEG-1 and MPEG-2 and other related standards, adding new features such as (extended) VRML support for 3D rendering, object-oriented composite files (including audio, video and VRML objects), support for externally-specified Digital Rights Management and various types of interactivity. AAC (Advanced Audio Coding) was standardized as an adjunct to MPEG-2 (as Part 7) before MPEG-4 was issued.

MPEG-4 is still a developing standard and is divided into a number of parts. Companies promoting MPEG-4 compatibility do not always clearly state which "part" level compatibility they are referring to. The key parts to be aware of are MPEG-4 part 2 (including Advanced Simple Profile, used by codecs such as DivX, Xvid, Nero Digital and 3ivx and by Quicktime 6) and MPEG-4 part 10 (MPEG-4 AVC/H.264 or Advanced Video Coding, used by the x264 encoder, by Nero Digital AVC, by Quicktime 7, and by high-definition video media like Blu-ray Disc).

What is AU?
The Au file format is a simple audio file format introduced by Sun Microsystems. The format was common on NeXT systems and on early web pages. Originally it was headerless, being simply 8-bit u-law encoded data at an 8000 Hz sample rate. Hardware from other vendors often used sample rates as high as 8192 Hz, often integer factors of video clock signals. Newer files have a header that consists of six 32-bit words, an optional information chunk and then the data (in big endian format). Although the format now supports many audio encoding formats, it remains associated with the u-law logarithmic encoding. This encoding was native to the SPARCstation 1 hardware, where SunOS exposed the encoding to apps through the /dev/audio interface. This encoding and interface became a de facto standard for Unix sound.