Tag editor

A tag editor (or tagger) is a piece of software that supports editing metadata of multimedia file formats, rather than the actual file content. These are mainly taggers for common audio tagging formats like ID3, APE, and Vorbis comments (for example Windows Media Player and iTunes), but can also be taggers for JPEG, PDF and TIFF metadata (for example iPhoto).

A common purpose of tag editors is to correct or update metadata and enable sorting and grouping of multimedia files, for example music collections. This often happens in a batch processing mode so that one doesn't have to manually edit every file on its own.

Media players such as iTunes, Foobar2000 or Winamp, as well as dedicated tag editing programs allow users to manually edit tag and song file information, including composer and release year. Dedicated tag editors may feature batch processing and creating tags from file names and vice versa.

One type of tag editor compares the existing metadata in an audio file's tags with the information from online music databases, such as Gracenote, Discogs, freedb, Zortam Music Internet Database (ZMLIMD) or MusicBrainz. Once a match is found, complimentary metadata information may be downloaded. This process is semi-automatic because more than one match may be found.

An acoustic fingerprint is a unique code generated from an audio waveform. Depending upon the particular algorithm, acoustic fingerprints can be used to automatically categorize or identify an audio sample. Practical uses of acoustic fingerprinting include broadcast monitoring, identification of music and ads being played, peer-to-peer network monitoring, sound effect library management, and video identification.

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Wikipedia