MP3Gain
Encyclopedia
MP3Gain is an audio normalization
software tool. The tool is available on multiple platforms
and is free software
. It analyzes the MP3
and reversibly changes its volume. The volume can be adjusted for single files or as album where all files would have the same perceived loudness
. It is an implementation of ReplayGain.
(volume adjustment), either per track or per album, using the ReplayGain algorithm. It then modifies the overall volume scale factor in each MP3 frame, and writes undo information as a tag (in APEv2, or ID3v2
format) making this a reversible process. The scale factor modification can be reversed using the information in the added tag and the tag may be removed. MP3Gain does not introduce any digital generation loss because it does not decode and re-encode
the file.
Audio normalization
Audio normalization is the application of a constant amount of gain to an audio recording in order to bring the average or peak amplitude to a target level ....
software tool. The tool is available on multiple platforms
Cross-platform
In computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms...
and is free software
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...
. It analyzes the MP3
MP3
MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression...
and reversibly changes its volume. The volume can be adjusted for single files or as album where all files would have the same perceived loudness
Loudness
Loudness is the quality of a sound that is primarily a psychological correlate of physical strength . More formally, it is defined as "that attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud."Loudness, a subjective measure, is often...
. It is an implementation of ReplayGain.
Modification
MP3Gain first computes the desired gainGain
In electronics, gain is a measure of the ability of a circuit to increase the power or amplitude of a signal from the input to the output. It is usually defined as the mean ratio of the signal output of a system to the signal input of the same system. It may also be defined on a logarithmic scale,...
(volume adjustment), either per track or per album, using the ReplayGain algorithm. It then modifies the overall volume scale factor in each MP3 frame, and writes undo information as a tag (in APEv2, or ID3v2
ID3
ID3 is a metadata container most often used in conjunction with the MP3 audio file format. It allows information such as the title, artist, album, track number, and other information about the file to be stored in the file itself....
format) making this a reversible process. The scale factor modification can be reversed using the information in the added tag and the tag may be removed. MP3Gain does not introduce any digital generation loss because it does not decode and re-encode
Transcode
Transcoding is the direct digital-to-digital data conversion of one encoding to another, such as for movie data files or audio files. This is usually done in cases where a target device does not support the format or has limited storage capacity that mandates a reduced file size, or to convert...
the file.