Convert M4A to AAC

Apple Inc. has designed M4A open source format on the basis of QuickTime Fike. Now the format is being promoted in iTunes store. It is a multimedia container intended for placement of sound components, as well as other data, such as images. MPEG-4 files may be stored with extensions M4A and MP4. In the latter case, they contain video as well.

Alongside these sound formats, MPEG-4 allows for lossy compaction, through FFC Codec. However, it is possible to provide a lossless compaction thanks to Apple Lossless format. The files may be played on Windows PCs via iTunes, Windows Media Player 12, KSP Sound Player, Winamp and some other programs. With iTunes, the data can be converted into Windows-supported audio formats.

In comparison with its predecessor MP3, M4A format provides with better sound quality and smaller file size. Thanks to lossless compaction, the data may be easily converted in both direction with no deterioration in quality. The sound data encoded with ACC compression, which reduces the file size considerably.

Due to protection technology DRM, MP4 files cannot be easily distributed, while it is much simpler to replicate files in M4A; that is why “Apple Lovers” prefer the latter format. With M4A, it is possible to buy music in iTunes, as well as download it into smartphones or other devices.

A proprietary format with lossy compression, which have been created as an alternative for MP3 with a higher quality of coding. Overtones out of human perception are being removed. AAC is two times less than MP3, which means 1/10 of CD digital data.

The format has being widely used since 1997 as the seventh release of MPEG-2 family. As it is supplied by hardware players, the format is highly demanded by music fans. It has been widely spread in Apple production and is being used by default in iTunes.

The format conception is similar to MP3, but it is more advanced. Being able to execute larger compression, it is represented as a separate segment of MPEG-4 standard which is used for creation of compact audio files. AAC is highly efficient with variable and continuous bitrate, with sampling frequency of 8-96 KHz.

The current version complies with the standard of ISO/IEC 14496-3. Compression is performed on the basis of auditory masking effect that provides with data reduction with no deterioration for sound quality.