MP3 To M4A

.mp3

MP3 is a digital music format which allows CD tracks to be reduced to around a tenth of their normal size without a significant loss of quality. MP3 gets rid of a lot of the information recorded in a song that our ears are not able to hear and then uses complex algorithms to reduce the file size. This then enables you to get hundreds of songs on to a CD and it also has opened up a new market over the internet - the download market as download times have been significantly reduced.

MP3 is a digital format for storage of audio files designed by MPEG programmers. It is one of the most required codecs for digital coding. The format is widely used in various file-sharing sites for evaluation downloading.

With this format, it is possible to compress CD tracks up to 1/10 of their original size while maintaining high playback quality. Overtones, which cannot be perceived by a human ear, are removed. Complex algorithms allow for smaller size of tracks. As a result, one compact disk can contain several hundred songs. MP3 is compatible with all most popular operating systems and supported by the most of modern DVD-players and music systems.

The MP3 format is a lossy format. That means that an MP3 file does not contain 100% of the original audio information. Instead, MP3 files use perceptual coding. In other words, that means it removes the information that your ear doesn't notice thereby making the file smaller. The reason lossy formats are used over RAW is that RAW audio files are too large to travel over the internet at any great speed. By using lossy formats it enables even dial up users to download mp3 files at a reasonable speed. RAW file formats generally require 176,000 bytes per second compared to a lossy format which requires 17,600. The difference is massive and so are the download times.

Prior to MP3 introduction, MPEG-1 had been widely used. That format contained not only audio data, but images as well. MP3 breaks an audio file into parts of the same length. When the processing is over, each part is packed into its own frame. It involves the technology of spectral limit that requires a continuous input signal to provide the use of two adjacent frames.

When spectral deleting is over, the file is to be compressed with mathematic methods. If necessary, compression rate can be changed, even inside the same frame. Files of 128 kbit/s have 11-fold compression. Further reduction of the file size will lead to significant deterioration in sound quality.

Moving Picture Experts Group

audio/mpeg

audio/mp3

audio/mpeg3

audio/mpg

audio/x-mpeg

audio/x-mpeg-3

audio/x-mpegaudio

audio/x-mpg

audio/x-mp3

.m4a

M4A files are a type of audio file developed and popularised by Apple. Since 2007, music purchased through the iTunes store has been in m4a format, therefore accounting for over 15 billions files worldwide. MP4 and M4A files are often confused, and the two are quite similar, being both based on the MPEG-4 codec. However, M4A is a file comprising solely of audio, whereas MP4 may also contain video.

Apple Inc. has designed M4A format on the basis of QuickTime Fike. Now the format is being promoted in iTunes. 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.

M4A files are superior to MP3 in terms of the scale of compression and audio quality. The M4A file uses Apple's codec and resides within the MPEG-4 container. The main benefit of M4A is that files are compressed but are lossless. This means they can be decoded back to the original quality they were at the point of compression. Another benefit of M4A files are that do not carry any Digital Rights Management (DRM) protection associated with other files meaning they are less restricted.

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 Loversprefer the latter format. With M4A, it is possible to buy music in iTunes, as well as download it into smartphones or other devices.

Apple

audio/mp4a-latm

audio/mpeg