Music is often a powerful motivator, whether you’re crushing another rep at the gym or relaxing after a long day. But digital music files can be huge in size, especially if you have a collection of songs or audiobooks to store.
Fortunately, mp3 is the oldest and most widely used standard for reducing media file size.
Definition
A patented digital audio compression format that uses a lossy data-compression algorithm to reduce file size. It’s a popular choice for music files, especially since it can be used on portable devices that don’t have much storage space.
It’s also popular for sharing and storing media on the internet because of its small file size. However, that can raise privacy concerns because anyone can download a file without the permission of the original owner.
Unleashing the Power of Lossless MP3: A Guide to Hi-Fi Audio
MP3 was developed in the late 1980s by Karlheinz Brandenburg at the Fraunhofer Institute for Digital Signal Processing in Germany. Its main components are the frame header and the data block. The frame header has a sync word and 3 bits that show that it is an MP3 file. The first 2 bits indicate that the frame is a Huffman coded frame and the last bit indicates that it is layer 3.
MP3 is an ISO-approved standard as part of the MPEG-1 and MPEG-2 video specifications. When used with an encoding algorithm that supports multiple bit rates, it can be compressed by up to 90% while maintaining CD-quality audio. This is how it became the most popular method for storing and playing music in digital form today.
Formats
In its most basic form, mp3 is a file format that encodes audio data. Using the MPEG-1 or MPEG-2 Audio Layer III codec, it can reduce the size of audio files up to ten times smaller than their original WAV or AIF formats while maintaining good quality.
It can be used to store and play music on a computer. It is also widely used for streaming audio over the internet and in digital devices.
Its small file size enables listeners to store five or ten songs on the same device that could only hold one uncompressed audio CD, and it requires less memory than other audio file formats. However, mp3 file compression can cause loss of audio detail and a muddiness to the sound, particularly when it uses a low bit rate such as 128 kbps. This can be corrected by using an equalizer on your mp3 player to boost frequencies that may have been lost in the encoding process.
Encoding
The mp3 file format is based on data compression to shrink the size of the original digital audio recording. This reduces the number of bits needed to store an audio clip without affecting sound quality. The compression technique used is called psychoacoustic modeling.
It allows the codec to discard any audio data that is inaudible and reduce the precision of audio components that are not critical to the listening experience. For example, a loud orchestra easily masks the sounds of any instruments playing softly, so a recording could save space by dropping the inaudible data of those instruments.
This allowed the resulting files to be stored on hard disks and transmitted over the Internet much more quickly than uncompressed LPCM audio. It also helped fuel the growth of music piracy sites like Napster and online music stores such as Apple iTunes and Rhapsody. Limited hard disk storage capacity was the major motivating factor for the development of mp3. MP3 encoders typically use constant bit rate encoding or variable bit rate (VBR) encoding to create files that are as small as possible without sacrificing quality.
Streaming
The mp3 file format is well supported by all major music players, and is widely used for streaming audio over the Internet. However, the compression involved makes it harder to download than a WAV file.
The use of mp3 allows webmasters to send music-on-demand to their readers without requiring them to download a whole CD worth of files, or even one song. This is called pseudo-streaming.
Real streams are usually sent as.pls files (MIME type audio/x-scpls), while pseudo-streams are sent as.M3U playlists. Your browser and your MP3 player must be configured to correctly handle these formats.
For your computer to properly play streamed mp3 files, it must have enough memory and CPU power to buffer the stream as it plays over your connection. If you have a slow Internet connection, it may be necessary to set your player to a higher buffer size than the default value. For example, the WinAmp player uses a setting named “bit reservoir,” which controls how many kilobytes of data are grabbed before a second of audio is played.