Crate lofty

This is a fork of Audiotags, adding support for more file types and (optionally) duration.

Parse, convert, and write metadata to audio files of different file types.

This crate aims to provide a unified trait for parsers and writers of different audio file formats. Without this crate, you would otherwise need to learn the different APIs in id3, mp4ameta, etc. in order to parse metadata in different file formats.

Supported Formats

File Format	Extensions	Read	Write	Duration	Metadata Format(s)
Ape	ape	X	X		APEv2
AIFF	aiff, aif	X	X		ID3v2
FLAC	flac	X	X		Vorbis Comments
MP3	mp3	X	X	X	ID3v2
MP4	mp4, m4a, m4b, m4p, m4v, isom	X	X		Vorbis Comments
Opus	opus	X			Vorbis Comments
Ogg	ogg, oga	X	X		Vorbis Comments
WAV	wav, wave	X	X		RIFF INFO, ID3v2

Examples

Guessing from extension

use lofty::{Tag, TagType};

let mut tag = Tag::new().read_from_path("tests/assets/a.mp3").unwrap();
tag.set_title("Foo");

assert_eq!(tag.title(), Some("Foo"));

Guessing from file signature

use lofty::Tag;

let mut tag_sig = Tag::new().read_from_path_signature("tests/assets/a.wav").unwrap();
tag_sig.set_artist("Foo artist");

assert_eq!(tag_sig.artist_str(), Some("Foo artist"));

Specifying a TagType

use lofty::{Tag, TagType};

let mut tag = Tag::new().with_tag_type(TagType::Mp4).read_from_path("tests/assets/a.m4a").unwrap();
tag.set_album_title("Foo album title");

assert_eq!(tag.album_title(), Some("Foo album title"));

Converting between TagTypes

use lofty::{Tag, TagType};

let mut tag = Tag::new().read_from_path("tests/assets/a.mp3").unwrap();
tag.set_title("Foo");

// You can convert the tag type and save the metadata to another file.
tag.to_dyn_tag(TagType::Mp4).write_to_path("tests/assets/a.m4a");
assert_eq!(tag.title(), Some("Foo"));

Features

Applies to all

• full - Combines both all_tags and duration (default)
• all_tags - Enables all formats
• duration - Provides the duration field in each tag

Individual formats

These features are available if you have a specific usecase, or just don’t want certain formats.

All format features a prefixed with format-

• format-ape
• format-flac
• format-id3
• format-mp4
• format-opus
• format-vorbis
• format-riff

Performance

Using lofty incurs a little overhead due to vtables if you want to guess the metadata format (from file extension). Apart from this, the performance is almost the same as directly calling the function provided from those ‘specialized’ crates.

No copies will be made if you only need to read and write metadata of one format. If you want to convert between tags, copying is unavoidable, no matter if you use lofty or use getters and setters provided by specialized libraries. Lofty is not making additional unnecessary copies.

Structs

Album	A struct for representing an album for convenience.
AnyTag	Used to convert between tags
Picture	Represents a picture, with its data and mime type.
Tag	A builder for Box<dyn AudioTag>. If you do not want a trait object, you can use individual types.

Enums

Error	Errors that could occur within Lofty.
Id3Format	ID3 tag’s underlying format
MimeType	Mime types for covers.
TagType	The tag type, based on the file extension.
VorbisFormat	File formats using vorbis comments

Traits

AudioTag	Combination of AudioTagEdit, AudioTagWrite, and ToAnyTag
AudioTagEdit	Implementors of this trait are able to read and write audio metadata.
AudioTagWrite	Functions for writing to a file
ToAny	Tag conversion to Any
ToAnyTag	Conversions between tag types

Type Definitions

PictureType	Alias for PictureType
Result	Type for the result of tag operations.