Terminology, 2 terminology – Sonnox Fraunhofer Pro-Codec User Manual
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2 TERMINOLOGY
2 Terminology
Bit rate
This is the number of bits transmitted or processed per unit of time, expressed here
in kilobits per second (kbps).
CBR
Constant Bit Rate –- bit rate remains the same for the duration of the audio signal.
VBR
Variable Bit Rate –- bit rate changes over time, based on the complexity of the signal.
In this case, the VBR value expressed is an average over the length of the file.
Encoder
In this context, an encoder converts an uncompressed LPCM audio stream into a
smaller, compressed format through the use of lossy compression. For HD-AAC, the
encoding process is lossless to the target bit depth.
Decoder
In this context, a decoder converts a compressed audio stream back into an
uncompressed LPCM audio stream.
Metadata
This is categorical information about a file, such as the song Title, Artist and Album.
Tag A tag is one specific piece of metadata, such as the song Title.