diff --git a/.gitignore b/.gitignore index ccf3631..59c5001 100644 --- a/.gitignore +++ b/.gitignore @@ -20,5 +20,5 @@ erl_crash.dump *.ez # Ignore package tarball (built via "mix hex.build"). -midi_tools-*.tar +midi_player-*.tar diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..f288702 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md index 87a55f5..d009461 100644 --- a/README.md +++ b/README.md @@ -1,21 +1,74 @@ -# MIDITools +# MIDIPlayer -**TODO: Add description** +A MIDI player for Elixir. -## Installation +## Prerequisites -If [available in Hex](https://hex.pm/docs/publish), the package can be installed -by adding `midi_tools` to your list of dependencies in `mix.exs`: +Install FluidSynth to play MIDI commands: -```elixir -def deps do - [ - {:midi_tools, "~> 0.1.0"} - ] -end +On Linux: + +```sh +sudo apt install libfluidsynth-dev ``` -Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc) -and published on [HexDocs](https://hexdocs.pm). Once published, the docs can -be found at [https://hexdocs.pm/midi_tools](https://hexdocs.pm/midi_tools). +On OSX: +```sh +brew install fluidsynth +``` + +Clone this repo or put the [Hex dependency](https://hex.pm/packages/midi_player) in your mix.exs: + +```elixir +{:midi_player, "~> 0.2.0"} +``` + +## Examples + +MIDIPlayer takes "events" which for example represent to play a note for a time span. +It then converts these events to MIDI commands and schedules them. + +First, let's create some events. +This plays a piano sound for the C note for 1 second: + +```elixir +iex> piano = MIDIPlayer.Event.note(0, 60, 0, 1000, 127) +``` + +We can change the instrument to a violin after one second like so: + +```elixir +iex> change = MIDIPlayer.Event.change_program(0, 1000, 41) +``` + +(Note that it could be simpler to use another MIDI channel for another instrument.) + +Finally, play two notes on the violin at the same time: + +```elixir +iex> violin1 = MIDIPlayer.Event.note(0, 67, 1000, 3000, 127) +iex> violin2 = MIDIPlayer.Event.note(0, 64, 1000, 3000, 127) +``` + +Now we are ready to play these events. +First start the player like so: + +```elixir +iex> {:ok, player} = MIDIPlayer.start_link() +``` + +Then load the events, and play them! + +```elixir +iex> MIDIPlayer.generate_schedule(player, [piano, change, violin1, violin2], 3000) +iex> MIDIPlayer.play(player) +``` + +## Thanks + +This project uses [MIDISynth](https://github.com/fhunleth/midi_synth) +for generating MIDI commands and operating the FluidSynth synthesizer. +It also uses [Timex](https://github.com/bitwalker/timex) +for timing related functionality. +Inspiration from [Beats](https://github.com/mtrudel/beats). \ No newline at end of file diff --git a/lib/midi_tools/player.ex b/lib/midi_player.ex similarity index 69% rename from lib/midi_tools/player.ex rename to lib/midi_player.ex index 8e77ddc..516d875 100644 --- a/lib/midi_tools/player.ex +++ b/lib/midi_player.ex @@ -1,18 +1,29 @@ -defmodule MIDITools.Player do +defmodule MIDIPlayer do use GenServer @moduledoc """ A GenServer for playing a schedule of MIDI commands at predefined times. """ + # TBD: I think cancelling the timer could introduce a race condition. + # Could maybe match timer's reference to saved one? + + @type schedule :: [{non_neg_integer(), binary()}] + # Client API + @midi_synth_args [:soundfont] + @doc """ Start the MIDI player. + + The soundfont path can be set with the :soundfont argument. """ - @spec start_link() :: GenServer.on_start() - def start_link do - GenServer.start_link(__MODULE__, nil, name: __MODULE__) + @spec start_link(GenServer.options()) :: GenServer.on_start() + def start_link(opts \\ []) do + init_args = Keyword.take(opts, @midi_synth_args) + server_args = Keyword.drop(opts, @midi_synth_args) + GenServer.start_link(__MODULE__, init_args, server_args) end @doc """ @@ -24,58 +35,72 @@ defmodule MIDITools.Player do The duration makes sure the player plays a (potential) pause after the last midi command. - See `MIDITools.Event` to create events. + See `MIDIPlayer.Event` to create events. """ - @spec generate_schedule([MIDITools.Event.t()], non_neg_integer()) :: :ok - def generate_schedule(events, duration) when duration > 0 do - GenServer.call(__MODULE__, {:generate_schedule, events, duration}) + @spec generate_schedule(GenServer.server(), [MIDIPlayer.Event.t()], non_neg_integer()) :: :ok + def generate_schedule(player, events, duration) when duration > 0 do + GenServer.call(player, {:generate_schedule, events, duration}) end @doc """ Play the current MIDI schedule from the start. """ - @spec play() :: :ok - def play do - GenServer.call(__MODULE__, :play) + @spec play(GenServer.server()) :: :ok + def play(player) do + GenServer.call(player, :play) end @doc """ Set the player on repeat or not. """ - @spec set_repeat(boolean()) :: :ok - def set_repeat(repeat) when is_boolean(repeat) do - GenServer.call(__MODULE__, {:set_repeat, repeat}) + @spec set_repeat(GenServer.server(), boolean()) :: :ok + def set_repeat(player, repeat) when is_boolean(repeat) do + GenServer.call(player, {:set_repeat, repeat}) end @doc """ Stop the player and cancel the pause. """ - @spec stop_playing() :: :ok - def stop_playing do - GenServer.call(__MODULE__, :stop_playing) + @spec stop_playing(GenServer.server()) :: :ok + def stop_playing(player) do + GenServer.call(player, :stop_playing) end @doc """ - Pause the player. See `MIDITools.Player.resume/0` for resuming playback. + Pause the player. + + See `MIDIPlayer.resume/1` for resuming playback. """ - @spec pause() :: :ok | {:error, :already_paused | :not_started} - def pause do - GenServer.call(__MODULE__, :pause) + @spec pause(GenServer.server()) :: :ok | {:error, :already_paused | :not_started} + def pause(player) do + GenServer.call(player, :pause) end @doc """ Resume playback on the player after it has been paused. """ - @spec resume() :: :ok, {:error, :not_paused} - def resume do - GenServer.call(__MODULE__, :resume) + @spec resume(GenServer.server()) :: :ok | {:error, :not_paused} + def resume(player) do + GenServer.call(player, :resume) + end + + @doc """ + Get the current schedule of the player. + + The schedule is a list of tuples of a time in milliseconds and the + corresponding bitstream of MIDI commands to be played at that time. + The list is guaranteed to be ascending in time. + """ + @spec get_schedule(GenServer.server()) :: schedule() + def get_schedule(player) do + GenServer.call(player, :get_schedule) end # Server callbacks @impl GenServer - def init(_arg) do - {:ok, synth} = MIDISynth.start_link([]) + def init(args) do + {:ok, synth} = MIDISynth.start_link(args) {:ok, %{ @@ -100,15 +125,14 @@ defmodule MIDITools.Player do start_time = Timex.now() timer = start_timer(schedule, start_time) - {:reply, :ok, - %{reset(state) | timer: timer, start_time: start_time}} + {:reply, :ok, %{reset(state) | timer: timer, start_time: start_time}} end def handle_call({:set_repeat, repeat}, _from, state) do {:reply, :ok, %{state | repeat: repeat}} end - def handle_call(:stop_playing, _from, state) do + def handle_call(:stop_playing, _from, state) do {:reply, :ok, reset(state)} end @@ -143,6 +167,10 @@ defmodule MIDITools.Player do {:reply, :ok, %{state | timer: timer, start_time: start_time, pause_time: nil}} end + def handle_call(:get_schedule, _from, %{schedule: schedule} = state) do + {:reply, schedule, state} + end + @impl GenServer def handle_info( :play, @@ -210,7 +238,7 @@ defmodule MIDITools.Player do defp convert_events(events) do events - |> Enum.flat_map(&MIDITools.Event.convert/1) + |> Enum.flat_map(&MIDIPlayer.Event.convert/1) |> Enum.reduce(%{}, fn {time, midi}, acc -> Map.update(acc, time, midi, &<<&1::binary, midi::binary>>) end) diff --git a/lib/midi_tools/event.ex b/lib/midi_player/event.ex similarity index 62% rename from lib/midi_tools/event.ex rename to lib/midi_player/event.ex index 8d7d89c..18350d8 100644 --- a/lib/midi_tools/event.ex +++ b/lib/midi_player/event.ex @@ -1,6 +1,7 @@ -defmodule MIDITools.Event do +defmodule MIDIPlayer.Event do @moduledoc """ Several musical events which can be converted to MIDI commands. + All timings are in milliseconds. """ @@ -10,17 +11,6 @@ defmodule MIDITools.Event do """ defstruct channel: 0, tone: 0, start_time: 0, end_time: 0, velocity: 0 - - @spec new(MIDISynth.Command.channel(), non_neg_integer(), non_neg_integer(), non_neg_integer(), MIDISynth.Command.velocity()) :: %Note{} - def new(channel, tone, start_time, end_time, velocity) when start_time >= 0 and end_time > start_time do - %__MODULE__{ - channel: channel, - tone: tone, - start_time: start_time, - end_time: end_time, - velocity: velocity - } - end end defmodule ChangeProgram do @@ -29,11 +19,6 @@ defmodule MIDITools.Event do """ defstruct channel: 0, time: 0, program: 0 - - @spec new(MIDISynth.Command.channel(), non_neg_integer(), non_neg_integer()) :: %ChangeProgram{} - def new(channel, time, program) do - %__MODULE__{channel: channel, time: time, program: program} - end end @typedoc """ @@ -41,6 +26,30 @@ defmodule MIDITools.Event do """ @type t :: %Note{} | %ChangeProgram{} + @spec note( + MIDISynth.Command.channel(), + non_neg_integer(), + non_neg_integer(), + non_neg_integer(), + MIDISynth.Command.velocity() + ) :: %Note{} + def note(channel, tone, start_time, end_time, velocity) + when start_time >= 0 and end_time > start_time do + %Note{ + channel: channel, + tone: tone, + start_time: start_time, + end_time: end_time, + velocity: velocity + } + end + + @spec change_program(MIDISynth.Command.channel(), non_neg_integer(), non_neg_integer()) :: + %ChangeProgram{} + def change_program(channel, time, program) do + %ChangeProgram{channel: channel, time: time, program: program} + end + @doc """ Converts the event to a list of MIDI commands. """ diff --git a/lib/midi_tools.ex b/lib/midi_tools.ex deleted file mode 100644 index 19cf4a0..0000000 --- a/lib/midi_tools.ex +++ /dev/null @@ -1,18 +0,0 @@ -defmodule MIDITools do - @moduledoc """ - Documentation for `MIDITools`. - """ - - @doc """ - Hello world. - - ## Examples - - iex> MIDITools.hello() - :world - - """ - def hello do - :world - end -end diff --git a/mix.exs b/mix.exs index 57f98bf..427270f 100644 --- a/mix.exs +++ b/mix.exs @@ -1,21 +1,26 @@ -defmodule MIDITools.MixProject do +defmodule MIDIPlayer.MixProject do use Mix.Project def project do [ - app: :midi_tools, - version: "0.1.0", + app: :midi_player, + version: "0.2.0", elixir: "~> 1.10", start_permanent: Mix.env() == :prod, deps: deps(), # Docs - name: "MIDITools", - source_url: "https://github.com/pizzapim/midi_tools", - homepage_url: "https://github.com/pizzapim/midi_tools", + name: "MIDIPlayer", + source_url: "https://github.com/pizzapim/midi_player", + homepage_url: "https://github.com/pizzapim/midi_player", docs: [ - main: "MIDITools" - ] + extras: ["README.md"], + main: "readme" + ], + + # Hex stuff + description: description(), + package: package() ] end @@ -25,11 +30,26 @@ defmodule MIDITools.MixProject do ] end + defp description do + """ + A MIDI player for Elixir. + MIDIPlayer takes musical "events" like playing a note, converts them to MIDI commands, schedules them and then lets you play them. + """ + end + + defp package do + [ + name: "midi_player", + licenses: ["GPL-3.0-or-later"], + links: %{"GitHub" => "https://github.com/pizzapim/midi_player"} + ] + end + defp deps do [ {:midi_synth, "~> 0.4.0"}, {:timex, "~> 3.6"}, - {:ex_doc, "~> 0.22", only: :dev, runtime: false}, + {:ex_doc, "~> 0.22", only: :dev, runtime: false} ] end end diff --git a/test/event_test.exs b/test/event_test.exs new file mode 100644 index 0000000..5249c0f --- /dev/null +++ b/test/event_test.exs @@ -0,0 +1,27 @@ +defmodule MIDIPlayer.EventTest do + use ExUnit.Case + doctest MIDIPlayer.Event + + alias MIDIPlayer.Event + + test "note event" do + assert %Event.Note{channel: 0, tone: 60, start_time: 1, end_time: 1000, velocity: 127} = + Event.note(0, 60, 1, 1000, 127) + end + + test "change program event" do + assert %Event.ChangeProgram{channel: 0, time: 1, program: 40} = Event.change_program(0, 1, 40) + end + + test "note event conversion" do + note = Event.note(0, 60, 1, 1000, 127) + [note_on, note_off] = Event.convert(note) + assert {1, <<0x90, 60, 127>>} = note_on + assert {1000, <<0x80, 60, 64>>} = note_off + end + + test "change program event conversion" do + change_program = Event.change_program(0, 1, 40) + assert [{1, <<0xC0, 40>>}] = Event.convert(change_program) + end +end diff --git a/test/midi_tools_test.exs b/test/midi_tools_test.exs deleted file mode 100644 index 3687866..0000000 --- a/test/midi_tools_test.exs +++ /dev/null @@ -1,8 +0,0 @@ -defmodule MIDIToolsTest do - use ExUnit.Case - doctest MIDITools - - test "greets the world" do - assert MIDITools.hello() == :world - end -end diff --git a/test/player_test.exs b/test/player_test.exs new file mode 100644 index 0000000..9fb71bf --- /dev/null +++ b/test/player_test.exs @@ -0,0 +1,59 @@ +defmodule MIDIPlayerTest do + use ExUnit.Case + doctest MIDIPlayer + + alias MIDIPlayer, as: Player + alias MIDIPlayer.Event + + setup do + {:ok, player} = Player.start_link([]) + [player: player] + end + + setup_all do + events = Enum.map(1..4, &Event.note(9, 51, &1 * 500, (&1 + 1) * 500, 127)) + duration = 2000 + [events: events, duration: duration] + end + + test "play", %{player: player, events: events, duration: duration} do + assert :ok = Player.generate_schedule(player, events, duration) + assert :ok = Player.play(player) + Process.sleep(2500) + end + + test "pause & resume", %{player: player, events: events, duration: duration} do + Player.generate_schedule(player, events, duration) + Player.play(player) + Process.sleep(1100) + assert :ok = Player.pause(player) + Process.sleep(500) + assert :ok = Player.resume(player) + Process.sleep(1400) + end + + test "pause & resume edge cases", %{player: player, events: events, duration: duration} do + Player.generate_schedule(player, events, duration) + assert {:error, :not_started} = Player.pause(player) + assert {:error, :not_paused} = Player.resume(player) + Player.play(player) + Player.pause(player) + assert {:error, :already_paused} = Player.pause(player) + end + + test "event conversion", %{player: player} do + event1 = Event.change_program(0, 1, 40) + event2 = Event.note(0, 60, 1, 1000, 127) + events = [event1, event2] + duration = 100 + assert :ok = Player.generate_schedule(player, events, duration) + + change_program = MIDISynth.Command.change_program(0, 40) + note_on = MIDISynth.Command.note_on(0, 60, 127) + note_off = MIDISynth.Command.note_off(0, 60) + + [command1, command2] = Player.get_schedule(player) + assert {1, <<^change_program::binary-size(2), ^note_on::binary-size(3)>>} = command1 + assert {1000, ^note_off} = command2 + end +end