# ID3

Read/Write mp3 ID3v2 tags. Can read v1 tags too. Using Rust and Rustler as a backbone.

This module uses [`rust-id3`](https://github.com/jameshurst/rust-id3/) inside, so it follows the restrictions there.
(Currently ID3v1/v2 reading is supported, and all writing will be done as ID3v2.4)

## Example

```elixir
iex> {:ok, tag} = ID3.get_tag("audio.mp3")
iex> tag
%ID3.Tag{
  album_artist: "Queen",
  artist: "Queen",
  date_recorded: ~N[1977-10-07 00:00:00],
  date_released: ~N[1981-11-02 00:00:00],
  disc: 1,
  duration: nil,
  genre: "Rock",
  pictures: [
    %ID3.Picture{
      data: <<255, 216, 255, 224, 0, 16, 74, 70, 73, 70, 0, 1, 1, 0, 0, 72, 0,
        72, 0, 0, 255, 225, 3, 88, 69, 120, 105, 102, 0, 0, 77, 77, 0, 42, 0, 0,
        0, 8, 0, 9, ...>>,
      description: "",
      mime_type: "image/jpeg",
      picture_type: :CoverFront
    }
  ],
  title: "We Will Rock You",
  total_discs: 1,
  total_tracks: 17,
  track: 16,
  year: 1981
}
```

Read the [Documents](https://hexdocs.pm/id3/ID3.html) to know how to use.

## Installation

[Installation from Hex](https://hex.pm/packages/id3):
the package can be installed by adding `id3` to your list of dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:id3, "~> 0.2.0"}
  ]
end
```

### Rust is needed!

Before doing `mix deps.get`, make sure you have the latest Rust (`rustc`) installed on your environment.
Since version `0.2.0`, this project is using Rust 2018 edition, so versions over `1.3.1` are required.
The stable build should be good enough.

If it's your first time playing with Rust, [install `rustup`](https://www.rust-lang.org/tools/install). Follow the instructions and it will install the latest stable Rust too.

## Hey, this is slow :(

Maybe you are booting your application *not* in `:prod` mode.
When `ID3` is compiled in `:prod` mode, the Rust source will be compiled in "release" mode, which makes it optimized for performance. It has significant improvements on speed.

For `iex`, you can do `env MIX_ENV=prod iex -S mix` to compile/boot in `:prod` mode.

If you're already doing that and still is slow, report me, or please feel free to contribute :)
Both Elixir and Rust aspects of this library may be the problem.

## Contribution
Please feel free to open any issues or pull requests!