Description of the main audio formats. Audio file formats

Surely, many users prefer to use their home computer not only as a workhorse, but also as a multimedia center where they can watch movies or family photos, as well as listen to their favorite music. Although compact digital players or mobile phones are certainly more suitable for listening to musical compositions, but unlike them, a computer can not only play music.

No matter how big the built-in memory of your music player is, it will most likely be difficult to store your entire music library on it. Plus, you can create, edit, organize, and search for music with your PC. Also, don’t forget that there are around three dozen common digital audio formats today, and most players are far from omnivorous and can only play a few of them.

So why do you need to create so many music formats to store one type of content? The fact is that, in the vast majority of cases, the sound is stored in “compressed” form, since one minute of uncompressed composition occupies about 10 MB on the hard disk. On the one hand, this seems not to be much, but on the other, if you are a music lover and your collection consists of several hundred or even thousands of songs, then it is clear that the sound must be compressed to reduce the space it occupies in electronic media.

Various special algorithms are used to compress music files, which subsequently determine the structure and presentation of the audio data, or so-called digital audio file formats. All audio formats can be divided into three groups: uncompressed audio formats, lossless compression, and lossy compression.

No compression
One of the most widespread formats related to this type is the well-known WAV. The sound of files with this extension is stored without compression or changes. It is true that much more space is required to store uncompressed files and therefore WAV is more widely used only in professional audio and video applications, where the sound should not have a loss of quality before processing. Keeping ordinary musical compositions in this form is unwarranted waste.

To play WAV files, you do not need any special software, as all media players understand this format, including the standard Windows Media audio player built into the Windows system.

Another format used to store uncompressed audio that is worth mentioning is Apple’s development called AIFF (Audio Interchange File Format). As you may have guessed, it is most commonly used on Macintosh computers running Mac OS X.

Lossless compression (lossless)
Lossless compression algorithms for audio files work on the principle of conventional file cabinets. They do not provide the highest level of compression (40 to 60%), while they have virtually no effect on sound quality. It is also worth noting that in this case, the encrypted data can be fully restored to its original form. Therefore, the use of lossless compression is most often used in cases where it is important to preserve the identity of the compressed data with respect to the original.

The most popular audio formats in this group are FLAC (Free Lossless Audio Codec), APE (Monkey’s Audio), WMA (Windows Media Lossless), and ALAC (Apple Lossless Audio Codec). Each has its own pros and cons. For example, the APE codec offers slightly better compression gains, while FLAC is more common. In general, all true music lovers store their music collections in lossless formats, since they do not remove any data from the audio stream and files created with these codecs can be listened to even on high-quality stereos.

Frequently asked questions about audio formats

The rapid development of computer technology and the Internet has led to the need to create digital formats that could be stored and reproduced on computers without the use of any physical medium. As a result, various types of digital audio formats have been developed.

Types of digital audio formats
All digital audio formats can be divided into 3 groups according to the principle (codec) used to compress audio data, namely:

Lossy formats
These are audio formats that use a lossy compression method for audio data. That is, when encoding a digital audio recording with any of the lossy codecs, certain changes are made to the audio data. This can significantly reduce the size of the resulting file, but at the same time leads to a deterioration in sound quality. The most popular lossy formats include MP3, WMA, Ogg Vorbis, AAC, and others.

Advantages and disadvantages of lossy audio formats
The main advantage of lossy formats is the small file size, while maintaining acceptable quality for listening. Furthermore, these audio formats are compatible with the vast majority of electronic devices and music players, including home audio systems, radio recorders, and MP3 players.

The main drawback is the loss of sound quality compared to the original. If you convert an audio recording from an original licensed audio CD to a lossy format, when you play the resulting file, the sound will be worse than that of the source.

Lossy formats sound bad?
No way. First, when lossy encoding, there is a choice of compression ratio and sound quality. For example, if we are talking about the MP3 format, then to record a voice (audiobooks, audio tracks for a textbook in a foreign language), the CBR 128 kbps quality will be enough, but for music, the ideal option is CBR 320 kbps. It is worth noting that CBR is short for ConstantBit Rate, which stands for Constant Bitrate.

Second, the compression process uses the principle of removing from the recording those frequencies and sounds that a person cannot hear by nature. There is an opinion, confirmed by many experiments, that music compositions in high quality MP3 format (CBR 320 kbps) cannot be distinguished by ear from the original recording or from a licensed audio CD purchased from a store.

Lossless audio format
This is a type of digital audio format in which the audio data is encoded without loss of quality. The sound will not differ from the source in any way, be it a licensed music CD (CDA format) or a digitized vinyl head, saved in uncompressed WAV format (for Windows) or its analog AIFF (for iOS). The most popular lossless formats are FLAC, Monkey’s Audio, ALAC, WavPack, MWA Lossless.

This makes lossless audio formats ideal for listening to music on good audio equipment. For example, in high-end home speakers or Hi-Fi systems and high-end headphones.

Advantages and disadvantages of lossless formats
The main advantage of lossless audio formats is that during encoding and decoding, the program does not remove any data from the audio stream. Because of this, when playing such files, the listener receives the original sound without disturbance.
But lossless audio formats also have a major drawback. The fact is that many devices for playing sound files do not yet support these formats. You can solve the problem by purchasing the right type of equipment, for example a portable Hi-Fi player or a media player, as well as a home audio system that supports lossless audio formats.

Main digital audio formats

–MP3: was created by Moving Pictures Experts Group (MPEG), which created and continues to create standards for storing and transmitting audio and video in digital format. In its entirety, the format is called: MPEG-1 / MPEG-2 Layer 3 (MP3). It is the most popular music storage format in the world today.

MP3 simultaneously compresses data and processes audio to obtain the smallest possible file size. The bit rate can vary from 8 Kb / s to 320 Kb / s, the sampling rate from 16 kHz to 48 kHz. The goal of processing the original recording with the MP3 compression algorithm is to compress the information as little as possible. So if in its original form a song occupies around 70 MB of memory, then in MP3 format with acceptable quality it will only take around 7-8 MB, as you can see, the gain is significant, although it is achieved by degrading the sound quality .

–AAC: The format has become popular because Apple has adopted it as a standard for storing, selling and distributing music in its ecosystem and iTunes. AAC is very similar to MP3 in terms of audio processing during encoding, although it gives a slightly better result.
Furthermore, AAC not only compresses the data, but also performs sound processing, removing a certain type of data, thus achieving significant savings in memory for storing music. The bit rate can range from 8 kbps to 320 kbps, the sample rate ranges from 8 kHz to 96 kHz. With more sophisticated and sophisticated encoding and compression algorithms, AAC music can sound better than MP3 and take up less memory. Another advantage of the AAC format is that it supports up to 48 channels, while MP3 only supports 2.

–WMA: format developed by Microsoft to compete with MP3. During encoding, data is compressed, music is processed, and parts of it are removed, saving memory. However, there is a variation of the format called WMA Lossless that preserves the quality of the original sound. The vast majority of modern phones, players and computers support this format and there should be no problems with its playback. However, some computers may have a hard time playing them, so if you want maximum compatibility, MP3 may be worth choosing.

–FLAC: Developed by the Xiph.Org organization, this format is free for any type of use, so it is quite widespread these days.
FLAC uses data compression, however it preserves the original sound quality of the recording. music is not processed. The recording quality can be 32-bit / 96 kHz (this is significantly higher than the recording quality of CDs, which is 16-bit / 44.1 kHz). The data compression algorithm can save up to 30% memory compared to the original recording, while maintaining perfect sound quality. It is for this reason that the FLAC format has become very common.

–ALAC: this format is analogous to FLAC, but made by Apple, whose full name is Apple Lossless Audio Codec. Its properties are the same as those of FLAC, but its advantage was that all Apple devices could work with it without the need to install third-party applications. Since iOS 11, the FLAC format has also become fully compatible with Apple devices, so the urgent need for ALAC has decreased significantly for the sake of freedom and the greater compatibility with other devices that FLAC offers.

–WAV: A format developed by Microsoft, this format stores the sound in its original form, so the files take up a lot of memory, although they preserve the perfect quality of the music.
WAV does not compress or process sound, we can say that it is an ideal format for storing master copies and for subsequent sound processing. Although there are certain encoding settings that allow you to compress data, they are generally not used. WAV files are similar in storage method to PCM and AIFF formats.

–AIFF: a format also developed by Apple, the full name is Audio Interchange File Format. The main goal is to store music on Apple computers in its original form.
AIFF doesn’t compress data or perform any sound processing, so like WAV it takes up a lot of memory. The best sound storage format if you want to keep processing it in an editor or convert it to other formats on Mac computers.

–PCM: This format is used for digital recording of analog signals, which is sound. It is a standard for recording audio to CDs, but can also be used to store music digitally in computer memory. PCM does not compress audio, ideal for storing master copies of music or for professional audio work.