Recorded sound is stored in many formats. The need to save space on the storage device is opposed to sound quality. The smaller the sound file for a given recording the poorer the sound quality. This is not true for lossless compression methods, where the quality is preserved also in smaller sound file sizes.
The sound quality is determined by the bit rate, which is the number of samples per second times the number of bits per sample. It also depends on number of audio channels (mono, stereo, multichannel) and compression method.
The most common are lossy compression formats as MP3, OGG Vorbis, AAC and many others. For example, MP3 files commonly have a bit rate of 128 kbit/s, because it typically offers adequate audio quality in a relatively small space. MP3 has a maximum bit rate of 320 kbit/s.
By contrast, uncompressed audio as stored on an Audio CD has a bit rate of 1,411.2 kbit/s, or four times the best MP3 can do, and twelve times that of common MP3 files.
The WAV, AIFF or AU audio file formats can store audio using various bit rates, in accordance with the number of channels and compression. They often store uncompressed PCM audio with a bit rate of 1,411.2 kbit/s.
There are also lossless compression formats, such as FLAC, ALAC, Monkey's Audio and many others, which preserve quality of original uncompressed audio, but can reduce the needed storage space. Advantageously, these lossless formats can also store metadata (eg. images, title, artist, album, label, etc.) like lossy formats can, which cannot be done with pure uncompressed formats like WAV, AIFF, AU.
The sound quality is determined by the bit rate, which is the number of samples per second times the number of bits per sample. It also depends on number of audio channels (mono, stereo, multichannel) and compression method.
The most common are lossy compression formats as MP3, OGG Vorbis, AAC and many others. For example, MP3 files commonly have a bit rate of 128 kbit/s, because it typically offers adequate audio quality in a relatively small space. MP3 has a maximum bit rate of 320 kbit/s.
By contrast, uncompressed audio as stored on an Audio CD has a bit rate of 1,411.2 kbit/s, or four times the best MP3 can do, and twelve times that of common MP3 files.
The WAV, AIFF or AU audio file formats can store audio using various bit rates, in accordance with the number of channels and compression. They often store uncompressed PCM audio with a bit rate of 1,411.2 kbit/s.
There are also lossless compression formats, such as FLAC, ALAC, Monkey's Audio and many others, which preserve quality of original uncompressed audio, but can reduce the needed storage space. Advantageously, these lossless formats can also store metadata (eg. images, title, artist, album, label, etc.) like lossy formats can, which cannot be done with pure uncompressed formats like WAV, AIFF, AU.
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