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There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + 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 AGPL, see +. diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,51 @@ +# herald: sheet music in Haskell + +[![CI](https://github.com/joaquin-rossi/herald/actions/workflows/ci.yml/badge.svg)](https://github.com/joaquin-rossi/herald/actions/workflows/ci.yml) + +Haskell library for writing musical scores as code and synthesizing them into audio. + +Original idea: https://www.youtube.com/watch?v=FYTZkE5BZ-0 + +## Features + +- Named pitches, key signatures and accidentals that last until the bar line +- Note values, dots, ties, chords and trills +- Time signatures, with every bar checked +- Dynamics +- Equal temperament and historical tunings +- Several voices, each with its own instrument and stereo position +- Mono or stereo WAV output and playback + +Instruments: `pureTone`, `additive`, `organ`, `harpsichord`. + +## Example + +```haskell +import Herald + +melody :: Score m => m () +melody = do + setKey gMinor + tellNotes quarter [g4, b4, a4, g4] + tellBar + tellNote whole g4 + +main :: IO () +main = + either (putStrLn . displayScoreError) (saveWav "melody.wav") $ + playScoreMono defaultConfig [(defaultVoice, melody)] +``` + +## Demo + +```sh +cabal run herald-demo -- play little-fugue # requires ffplay +``` + +Little Fugue in G minor ([source](https://www.mit.edu/~jcb/little-fugue-two-violins.abc)): + +https://github.com/user-attachments/assets/ad373e14-ba8c-4924-a4e0-e839ccfaa71f + +Happy Birthday: + +https://github.com/user-attachments/assets/da93b721-d94f-4736-bea8-e08e566b3189 diff --git a/herald.cabal b/herald.cabal new file mode 100644 --- /dev/null +++ b/herald.cabal @@ -0,0 +1,72 @@ +cabal-version: 3.0 +name: herald +version: 0.1.0.1 +synopsis: Write sheet music as Haskell code and synthesize it +description: + Herald synthesizes music from scores written as Haskell code, with named + pitches, key signatures, checked bars, ties, dynamics and several voices. + Voices are performed by simple instruments (pure tones, additive, organ + and a Karplus-Strong harpsichord) in equal temperament or historical + tunings, and rendered to mono or stereo WAV or played through ffplay. + Start with the "Herald" module, which re-exports the whole library. +homepage: https://github.com/joaquin-rossi/herald +bug-reports: https://github.com/joaquin-rossi/herald/issues +license: AGPL-3.0-or-later +license-file: LICENSE +author: Joaquín Rossi +maintainer: joaquin@joaquinrossi.net +category: Sound +build-type: Simple +tested-with: GHC ==9.10.3 || ==9.12.4 || ==9.14.1 +extra-doc-files: README.md + +source-repository head + type: git + location: https://github.com/joaquin-rossi/herald.git + +common common + default-language: GHC2024 + ghc-options: + -Wall + -Wcompat + -Widentities + -Wincomplete-record-updates + -Wmissing-export-lists + -Wredundant-constraints + -Wunused-packages + +library + import: common + hs-source-dirs: src + exposed-modules: + Herald + Herald.Performance + Herald.Performance.Instrument + Herald.Score + Herald.Score.Duration + Herald.Score.Dynamic + Herald.Score.Pitch + Herald.Sound + Herald.Sound.IO + Herald.Tuning + + build-depends: + base >=4.20 && <4.23, + bytestring >=0.12 && <0.13, + containers >=0.7 && <0.9, + mtl >=2.3.1 && <2.4, + process >=1.6.19 && <1.7, + vector >=0.13.1 && <0.14, + +test-suite herald-test + import: common + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Main.hs + build-depends: + base, + bytestring, + herald, + tasty >=1.4.2 && <1.6, + tasty-hunit >=0.10 && <0.11, + vector, diff --git a/src/Herald.hs b/src/Herald.hs new file mode 100644 --- /dev/null +++ b/src/Herald.hs @@ -0,0 +1,23 @@ +-- | Write sheet music as Haskell code and synthesize it. +module Herald + ( module Herald.Score, + module Herald.Score.Pitch, + module Herald.Score.Duration, + module Herald.Score.Dynamic, + module Herald.Performance, + module Herald.Performance.Instrument, + module Herald.Tuning, + module Herald.Sound, + module Herald.Sound.IO, + ) +where + +import Herald.Performance +import Herald.Performance.Instrument +import Herald.Score +import Herald.Score.Duration +import Herald.Score.Dynamic +import Herald.Score.Pitch +import Herald.Sound +import Herald.Sound.IO +import Herald.Tuning diff --git a/src/Herald/Performance.hs b/src/Herald/Performance.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Performance.hs @@ -0,0 +1,280 @@ +-- | Renders "Herald.Score" voices to sound. +-- +-- >>> let short = setMeter (Meter 4 4) >> tellNotes quarter [c4, d4, e4] >> tellBar +-- >>> either displayScoreError (const "ok") (playScoreMono defaultConfig [(defaultVoice, short)]) +-- "voice 1, bar 1: the bar has 3.0 beats but the meter has 4.0" +module Herald.Performance + ( Performance, + ScoreConfig (..), + defaultConfig, + VoiceConfig (..), + defaultVoice, + playScoreMono, + playScoreStereo, + ScoreError (..), + ErrorReason (..), + displayScoreError, + ) +where + +import Control.Monad (forM_, when, zipWithM) +import Control.Monad.Except (MonadError (..)) +import Control.Monad.Reader +import Control.Monad.State.Strict +import Control.Monad.Writer.Strict +import Data.Map.Strict (Map) +import Data.Map.Strict qualified as Map +import Data.Vector.Unboxed qualified as V +import Herald.Performance.Instrument +import Herald.Score +import Herald.Score.Duration +import Herald.Score.Dynamic +import Herald.Score.Pitch +import Herald.Sound +import Herald.Tuning + +-- | Shared by every voice. +data ScoreConfig = ScoreConfig + { tempo :: Bpm, + tuning :: Tuning + } + +-- | 120 bpm in equal temperament at 440 Hz. +defaultConfig :: ScoreConfig +defaultConfig = + ScoreConfig + { tempo = 120, + tuning = a440 + } + +-- | How a voice is performed. +data VoiceConfig = VoiceConfig + { instrument :: Instrument, + -- | Ignored by 'playScoreMono'. + pan :: Pan + } + +-- | The additive instrument, centred. +defaultVoice :: VoiceConfig +defaultVoice = + VoiceConfig + { instrument = additive, + pan = 0 + } + +-- | Voices and bars count from 1. +data ScoreError = ScoreError + { errorVoice :: Int, + errorBar :: Int, + errorReason :: ErrorReason + } + deriving (Show, Eq) + +-- | A notation mistake in a voice. +data ErrorReason + = -- | Actual and expected beats. + WrongBarLength Beats Beats + | TieToDifferentPitch + | UnfinishedTie + deriving (Show, Eq) + +-- | As in @voice 2, bar 49: the bar has 4.25 beats but the meter has 4.0@. +displayScoreError :: ScoreError -> String +displayScoreError (ScoreError v b reason) = + "voice " ++ show v ++ ", bar " ++ show b ++ ": " ++ case reason of + WrongBarLength actual expected -> + "the bar has " ++ show actual ++ " beats but the meter has " ++ show expected + TieToDifferentPitch -> "a tie continues into a different pitch" + UnfinishedTie -> "a tie is not followed by a note of the same pitch" + +-- | Voices can only use the 'Score' operations, not its state or errors. +newtype Performance a = Performance (Perform a) + deriving newtype (Functor, Applicative, Monad) + +instance Score Performance where + tellNote b p = Performance (noteP b p) + tellTie b p = Performance (tieP b p) + tellChord b ps = Performance (chordP b ps) + tellTrill b k p q = Performance (trillP b k p q) + tellRest b = Performance (soundP b silence) + tellBar = Performance barP + setKey k = Performance (modify' (\st -> st {stateKey = k})) + setMeter m = Performance (modify' (\st -> st {stateMeter = Just m})) + setDynamic d = Performance (modify' (\st -> st {stateDynamic = d})) + +type Perform = + ReaderT (ScoreConfig, VoiceConfig) (StateT PerformState (WriterT Track (Either ScoreError))) + +data PerformState = PerformState + { stateKey :: Key, + stateMeter :: Maybe Meter, + stateDynamic :: Dynamic, + stateBarAccidentals :: Map (Letter, Octave) Accidental, + stateBar :: Int, + stateBarBeats :: Beats, + stateTie :: Maybe Tie + } + +data Tie = Tie + { tieWritten :: (Letter, Octave), + tieSemitones :: Semitones, + tieDynamic :: Dynamic, + tieBeats :: Beats + } + +-- | Chunks joined once at the end: appending vectors note by note would be +-- quadratic. +newtype Track = Track [Sound] + deriving newtype (Semigroup, Monoid) + +-- | Perform the voices in mono. +playScoreMono :: ScoreConfig -> [(VoiceConfig, Performance ())] -> Either ScoreError Sound +playScoreMono config voices = balanceSound . map snd <$> performVoices config voices + +-- | Perform the voices in stereo. +playScoreStereo :: ScoreConfig -> [(VoiceConfig, Performance ())] -> Either ScoreError Stereo +playScoreStereo config voices = + balanceStereo . map (\(v, s) -> panSound (pan v) s) <$> performVoices config voices + +performVoices :: ScoreConfig -> [(VoiceConfig, Performance ())] -> Either ScoreError [(VoiceConfig, Sound)] +performVoices config = zipWithM perform [1 ..] + where + perform k (v, Performance voice) = + case runWriterT (execStateT (runReaderT (voice >> finishP) (config, v)) start) of + Left e -> Left e {errorVoice = k} + Right (_, Track chunks) -> Right (v, V.concat chunks) + start = + PerformState + { stateKey = cMajor, + stateMeter = Nothing, + stateDynamic = mezzoForte, + stateBarAccidentals = Map.empty, + stateBar = 1, + stateBarBeats = 0, + stateTie = Nothing + } + +finishP :: Perform () +finishP = do + requireNoTie + beats <- gets stateBarBeats + when (beats > 0) checkBar + +failWith :: ErrorReason -> Perform a +failWith reason = do + b <- gets stateBar + throwError (ScoreError 0 b reason) + +barP :: Perform () +barP = do + checkBar + modify' $ \st -> + st + { stateBar = stateBar st + 1, + stateBarBeats = 0, + stateBarAccidentals = Map.empty + } + +checkBar :: Perform () +checkBar = do + meter <- gets stateMeter + beats <- gets stateBarBeats + forM_ meter $ \m -> + when (abs (beats - meterBeats m) > 1e-9) $ + failWith (WrongBarLength beats (meterBeats m)) + +-- | A written accidental lasts until the end of the bar for that letter and +-- octave; an unwritten one comes from earlier in the bar, else the key. +resolve :: Pitch -> Perform Semitones +resolve p = do + k <- gets stateKey + case accidental p of + Just a -> do + modify' $ \st -> st {stateBarAccidentals = Map.insert here a (stateBarAccidentals st)} + pure (pitchSemitones k p) + Nothing -> do + written <- gets (Map.lookup here . stateBarAccidentals) + pure (pitchSemitones k p {accidental = written}) + where + here = (letter p, octave p) + +-- | Like 'resolve' without recording the accidental, for trill auxiliaries. +resolveAux :: Pitch -> Perform Semitones +resolveAux p = do + k <- gets stateKey + written <- gets (Map.lookup (letter p, octave p) . stateBarAccidentals) + pure (pitchSemitones k p {accidental = maybe written Just (accidental p)}) + +advance :: Beats -> Perform () +advance b = modify' (\st -> st {stateBarBeats = stateBarBeats st + b}) + +seconds :: Beats -> Perform Seconds +seconds b = asks (\(config, _) -> b * (60.0 / tempo config)) + +frequency :: Semitones -> Perform Hz +frequency n = asks (\(config, _) -> tune (tuning config) n) + +voiceInstrument :: Perform Instrument +voiceInstrument = asks (instrument . snd) + +emit :: Dynamic -> Sound -> Perform () +emit d s = tell $ Track [gain (dynamicGain d) s] + +soundP :: Beats -> (Seconds -> Sound) -> Perform () +soundP b sound = do + requireNoTie + t <- seconds b + d <- gets stateDynamic + emit d (sound t) + advance b + +requireNoTie :: Perform () +requireNoTie = do + t <- gets stateTie + forM_ t $ \_ -> failWith UnfinishedTie + +continueTie :: Beats -> Pitch -> Tie -> Perform Tie +continueTie b p t = do + when ((letter p, octave p) /= tieWritten t) $ failWith TieToDifferentPitch + advance b + pure t {tieBeats = tieBeats t + b} + +noteP :: Beats -> Pitch -> Perform () +noteP b p = + gets stateTie >>= \case + Nothing -> do + f <- resolve p >>= frequency + i <- voiceInstrument + soundP b (renderNote i f) + Just tie -> do + tie' <- continueTie b p tie + modify' (\st -> st {stateTie = Nothing}) + f <- frequency (tieSemitones tie') + t <- seconds (tieBeats tie') + i <- voiceInstrument + emit (tieDynamic tie') (renderNote i f t) + +tieP :: Beats -> Pitch -> Perform () +tieP b p = + gets stateTie >>= \case + Nothing -> do + n <- resolve p + d <- gets stateDynamic + advance b + modify' (\st -> st {stateTie = Just (Tie (letter p, octave p) n d b)}) + Just tie -> do + tie' <- continueTie b p tie + modify' (\st -> st {stateTie = Just tie'}) + +chordP :: Beats -> [Pitch] -> Perform () +chordP b ps = do + fs <- mapM (\p -> resolve p >>= frequency) ps + i <- voiceInstrument + soundP b (chord i fs) + +trillP :: Beats -> Int -> Pitch -> Pitch -> Perform () +trillP b k p q = do + f <- resolve p >>= frequency + g <- resolveAux q >>= frequency + i <- voiceInstrument + soundP b (trill i k f g) diff --git a/src/Herald/Performance/Instrument.hs b/src/Herald/Performance/Instrument.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Performance/Instrument.hs @@ -0,0 +1,67 @@ +-- | Instruments render a note of a frequency and duration, peaking at most 1. +module Herald.Performance.Instrument + ( Instrument (..), + pureTone, + additive, + organ, + harpsichord, + partials, + chord, + trill, + ) +where + +import Data.Vector.Unboxed qualified as V +import Herald.Sound + +-- | Renders a note of a frequency and duration. +newtype Instrument = Instrument {renderNote :: Hz -> Seconds -> Sound} + +-- | Sine partials as frequency and relative amplitude, with short attack and +-- release ramps. Partials above Nyquist are dropped to avoid aliasing. +partials :: [(Hz, Double)] -> Seconds -> Sound +partials ws t = mixSound [gain (a / total) (envelope (sine f t)) | (f, a) <- ws'] + where + ws' = filter ((< sampleRate / 2) . fst) ws + total = sum (snd <$> ws') + len = sampleCount t + ramp i = min 1.0 (fromIntegral i * 0.001) + envelope = V.imap (\i x -> ramp i * ramp (len - 1 - i) * x) + +-- | A single sine wave. +pureTone :: Instrument +pureTone = Instrument $ \f -> partials [(f, 1)] + +-- | Five slightly inharmonic partials. +additive :: Instrument +additive = Instrument $ \f -> partials (take 5 $ zip (inharmonics 0.001 f) (iterate (* 0.5) 1.0)) + +-- | Pipe organ stops. +organ :: Instrument +organ = Instrument $ \f -> partials [(f * r, a) | (r, a) <- stops] + where + stops = + [ (0.5, 0.5), -- 16' + (1, 1), -- 8' + (2, 0.6), -- 4' + (3, 0.3), -- 2 2/3' + (4, 0.4), -- 2' + (8, 0.2) -- 1' + ] + +-- | Faded out over the last 5 ms so notes cut short don't click. +harpsichord :: Instrument +harpsichord = Instrument $ \f t -> + let len = sampleCount t + fade = fromIntegral (sampleCount 0.005) + in V.imap (\i x -> min 1 (fromIntegral (len - 1 - i) / fade) * x) (pluck 0.996 f t) + +-- | Notes sounding together. +chord :: Instrument -> [Hz] -> Seconds -> Sound +chord i fs t = balanceSound [renderNote i f t | f <- fs] + +-- | @k@ equal notes alternating @f@ and @g@. +trill :: Instrument -> Int -> Hz -> Hz -> Seconds -> Sound +trill i k f g t = V.concat [renderNote i x (t / fromIntegral k') | x <- take k' (cycle [f, g])] + where + k' = max 1 k diff --git a/src/Herald/Score.hs b/src/Herald/Score.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Score.hs @@ -0,0 +1,44 @@ +-- | The language voices are written in. Interpreters are instances of +-- 'Score'; "Herald.Performance" renders to sound. +module Herald.Score + ( Score (..), + tellNotes, + ) +where + +import Herald.Score.Duration +import Herald.Score.Dynamic +import Herald.Score.Pitch + +-- | Pitches follow notation rules: an unwritten accidental comes from earlier +-- in the bar, else from the key (C major by default); a written one lasts +-- until the next 'tellBar'. +class (Monad m) => Score m where + -- | After 'tellTie', continues the tied note instead: same letter and + -- octave, keeping its accidental across bar lines. + tellNote :: Beats -> Pitch -> m () + + -- | Ties into the next note, which must have the same pitch. + tellTie :: Beats -> Pitch -> m () + + tellChord :: Beats -> [Pitch] -> m () + + -- | @tellTrill b k p q@: @k@ notes alternating @p@ and @q@. The accidental + -- of @q@ doesn't carry on through the bar. + tellTrill :: Beats -> Int -> Pitch -> Pitch -> m () + + tellRest :: Beats -> m () + + -- | Ends the bar, which must add up to the meter, and clears accidentals. + tellBar :: m () + + setKey :: Key -> m () + + -- | From then on, every bar must add up to it, including the last one. + setMeter :: Meter -> m () + + setDynamic :: Dynamic -> m () + +-- | Notes of the same length. +tellNotes :: (Score m) => Beats -> [Pitch] -> m () +tellNotes b = mapM_ (tellNote b) diff --git a/src/Herald/Score/Duration.hs b/src/Herald/Score/Duration.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Score/Duration.hs @@ -0,0 +1,42 @@ +-- | Durations in beats, where a quarter note is one beat. +module Herald.Score.Duration + ( Beats, + Bpm, + whole, + half, + quarter, + eighth, + sixteenth, + thirtySecond, + dotted, + Meter (..), + meterBeats, + ) +where + +-- | A duration in beats. +type Beats = Double + +-- | Beats per minute. +type Bpm = Double + +-- | Note values. +whole, half, quarter, eighth, sixteenth, thirtySecond :: Beats +whole = 4 +half = 2 +quarter = 1 +eighth = 1 / 2 +sixteenth = 1 / 4 +thirtySecond = 1 / 8 + +-- | One and a half times as long. +dotted :: Beats -> Beats +dotted = (* 1.5) + +-- | Time signature, as in @Meter 6 8@. +data Meter = Meter Int Int + deriving (Show, Eq) + +-- | Beats in a bar. +meterBeats :: Meter -> Beats +meterBeats (Meter n d) = fromIntegral n * 4 / fromIntegral d diff --git a/src/Herald/Score/Dynamic.hs b/src/Herald/Score/Dynamic.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Score/Dynamic.hs @@ -0,0 +1,24 @@ +-- | Dynamics as gains relative to 'mezzoForte', where voices start. +module Herald.Score.Dynamic + ( Dynamic (..), + pianissimo, + piano, + mezzoPiano, + mezzoForte, + forte, + fortissimo, + ) +where + +-- | A loudness. +newtype Dynamic = Dynamic {dynamicGain :: Double} + deriving (Show, Eq, Ord) + +-- | From /pp/ to /ff/. +pianissimo, piano, mezzoPiano, mezzoForte, forte, fortissimo :: Dynamic +pianissimo = Dynamic 0.35 +piano = Dynamic 0.5 +mezzoPiano = Dynamic 0.7 +mezzoForte = Dynamic 1 +forte = Dynamic 1.4 +fortissimo = Dynamic 2 diff --git a/src/Herald/Score/Pitch.hs b/src/Herald/Score/Pitch.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Score/Pitch.hs @@ -0,0 +1,494 @@ +-- | Written pitches and key signatures. Names are letter, @b@ (flat) or @s@ +-- (sharp), and octave: @c4@ is middle C, @bb4@ is B flat. +module Herald.Score.Pitch + ( Semitones, + Octave, + Letter (..), + Accidental (..), + Pitch (..), + flat, + sharp, + natural, + Key (..), + keyAccidental, + sharps, + flats, + cMajor, + gMinor, + pitchSemitones, + cb0, + c0, + cs0, + db0, + d0, + ds0, + eb0, + e0, + es0, + fb0, + f0, + fs0, + gb0, + g0, + gs0, + ab0, + a0, + as0, + bb0, + b0, + bs0, + cb1, + c1, + cs1, + db1, + d1, + ds1, + eb1, + e1, + es1, + fb1, + f1, + fs1, + gb1, + g1, + gs1, + ab1, + a1, + as1, + bb1, + b1, + bs1, + cb2, + c2, + cs2, + db2, + d2, + ds2, + eb2, + e2, + es2, + fb2, + f2, + fs2, + gb2, + g2, + gs2, + ab2, + a2, + as2, + bb2, + b2, + bs2, + cb3, + c3, + cs3, + db3, + d3, + ds3, + eb3, + e3, + es3, + fb3, + f3, + fs3, + gb3, + g3, + gs3, + ab3, + a3, + as3, + bb3, + b3, + bs3, + cb4, + c4, + cs4, + db4, + d4, + ds4, + eb4, + e4, + es4, + fb4, + f4, + fs4, + gb4, + g4, + gs4, + ab4, + a4, + as4, + bb4, + b4, + bs4, + cb5, + c5, + cs5, + db5, + d5, + ds5, + eb5, + e5, + es5, + fb5, + f5, + fs5, + gb5, + g5, + gs5, + ab5, + a5, + as5, + bb5, + b5, + bs5, + cb6, + c6, + cs6, + db6, + d6, + ds6, + eb6, + e6, + es6, + fb6, + f6, + fs6, + gb6, + g6, + gs6, + ab6, + a6, + as6, + bb6, + b6, + bs6, + cb7, + c7, + cs7, + db7, + d7, + ds7, + eb7, + e7, + es7, + fb7, + f7, + fs7, + gb7, + g7, + gs7, + ab7, + a7, + as7, + bb7, + b7, + bs7, + cb8, + c8, + cs8, + db8, + d8, + ds8, + eb8, + e8, + es8, + fb8, + f8, + fs8, + gb8, + g8, + gs8, + ab8, + a8, + as8, + bb8, + b8, + bs8, + ) +where + +import Data.Map.Strict (Map) +import Data.Map.Strict qualified as Map +import Data.Maybe + +-- | A distance in semitones. +type Semitones = Int + +-- | Octave 4 starts at middle C. +type Octave = Int + +-- | A letter name. +data Letter = C | D | E | F | G | A | B + deriving (Show, Eq, Ord, Enum, Bounded) + +-- | A flat, natural or sharp. +data Accidental = Flat | Natural | Sharp + deriving (Show, Eq, Ord, Enum, Bounded) + +-- | A written pitch. +data Pitch = Pitch + { letter :: Letter, + octave :: Octave, + -- | 'Nothing' when unwritten: the key decides. + accidental :: Maybe Accidental + } + deriving (Show, Eq) + +-- | Write an accidental. +flat, sharp, natural :: Pitch -> Pitch +flat p = p {accidental = Just Flat} +sharp p = p {accidental = Just Sharp} +natural p = p {accidental = Just Natural} + +-- | A key signature. +newtype Key = Key (Map Letter Accidental) + deriving (Show, Eq) + +-- | The accidental a key gives a letter. +keyAccidental :: Key -> Letter -> Accidental +keyAccidental (Key as) l = Map.findWithDefault Natural l as + +-- | Sharps added in the order F C G D A E B. +sharps :: Int -> Key +sharps n = Key $ Map.fromList [(l, Sharp) | l <- take n [F, C, G, D, A, E, B]] + +-- | Flats added in the order B E A D G C F. +flats :: Int -> Key +flats n = Key $ Map.fromList [(l, Flat) | l <- take n [B, E, A, D, G, C, F]] + +-- | Common keys. +cMajor, gMinor :: Key +cMajor = Key Map.empty +gMinor = flats 2 + +-- | Relative to A4. +pitchSemitones :: Key -> Pitch -> Semitones +pitchSemitones key (Pitch l o acc) = base l + offset (fromMaybe (keyAccidental key l) acc) + 12 * (o - 4) - 9 + where + base C = 0 + base D = 2 + base E = 4 + base F = 5 + base G = 7 + base A = 9 + base B = 11 + offset Flat = -1 + offset Natural = 0 + offset Sharp = 1 + +-- | Octave 0. +cb0, c0, cs0, db0, d0, ds0, eb0, e0, es0, fb0, f0, fs0, gb0, g0, gs0, ab0, a0, as0, bb0, b0, bs0 :: Pitch +c0 = Pitch C 0 Nothing +d0 = Pitch D 0 Nothing +e0 = Pitch E 0 Nothing +f0 = Pitch F 0 Nothing +g0 = Pitch G 0 Nothing +a0 = Pitch A 0 Nothing +b0 = Pitch B 0 Nothing +cb0 = flat c0 +db0 = flat d0 +eb0 = flat e0 +fb0 = flat f0 +gb0 = flat g0 +ab0 = flat a0 +bb0 = flat b0 +cs0 = sharp c0 +ds0 = sharp d0 +es0 = sharp e0 +fs0 = sharp f0 +gs0 = sharp g0 +as0 = sharp a0 +bs0 = sharp b0 + +-- | Octave 1. +cb1, c1, cs1, db1, d1, ds1, eb1, e1, es1, fb1, f1, fs1, gb1, g1, gs1, ab1, a1, as1, bb1, b1, bs1 :: Pitch +c1 = Pitch C 1 Nothing +d1 = Pitch D 1 Nothing +e1 = Pitch E 1 Nothing +f1 = Pitch F 1 Nothing +g1 = Pitch G 1 Nothing +a1 = Pitch A 1 Nothing +b1 = Pitch B 1 Nothing +cb1 = flat c1 +db1 = flat d1 +eb1 = flat e1 +fb1 = flat f1 +gb1 = flat g1 +ab1 = flat a1 +bb1 = flat b1 +cs1 = sharp c1 +ds1 = sharp d1 +es1 = sharp e1 +fs1 = sharp f1 +gs1 = sharp g1 +as1 = sharp a1 +bs1 = sharp b1 + +-- | Octave 2. +cb2, c2, cs2, db2, d2, ds2, eb2, e2, es2, fb2, f2, fs2, gb2, g2, gs2, ab2, a2, as2, bb2, b2, bs2 :: Pitch +c2 = Pitch C 2 Nothing +d2 = Pitch D 2 Nothing +e2 = Pitch E 2 Nothing +f2 = Pitch F 2 Nothing +g2 = Pitch G 2 Nothing +a2 = Pitch A 2 Nothing +b2 = Pitch B 2 Nothing +cb2 = flat c2 +db2 = flat d2 +eb2 = flat e2 +fb2 = flat f2 +gb2 = flat g2 +ab2 = flat a2 +bb2 = flat b2 +cs2 = sharp c2 +ds2 = sharp d2 +es2 = sharp e2 +fs2 = sharp f2 +gs2 = sharp g2 +as2 = sharp a2 +bs2 = sharp b2 + +-- | Octave 3. +cb3, c3, cs3, db3, d3, ds3, eb3, e3, es3, fb3, f3, fs3, gb3, g3, gs3, ab3, a3, as3, bb3, b3, bs3 :: Pitch +c3 = Pitch C 3 Nothing +d3 = Pitch D 3 Nothing +e3 = Pitch E 3 Nothing +f3 = Pitch F 3 Nothing +g3 = Pitch G 3 Nothing +a3 = Pitch A 3 Nothing +b3 = Pitch B 3 Nothing +cb3 = flat c3 +db3 = flat d3 +eb3 = flat e3 +fb3 = flat f3 +gb3 = flat g3 +ab3 = flat a3 +bb3 = flat b3 +cs3 = sharp c3 +ds3 = sharp d3 +es3 = sharp e3 +fs3 = sharp f3 +gs3 = sharp g3 +as3 = sharp a3 +bs3 = sharp b3 + +-- | Octave 4. +cb4, c4, cs4, db4, d4, ds4, eb4, e4, es4, fb4, f4, fs4, gb4, g4, gs4, ab4, a4, as4, bb4, b4, bs4 :: Pitch +c4 = Pitch C 4 Nothing +d4 = Pitch D 4 Nothing +e4 = Pitch E 4 Nothing +f4 = Pitch F 4 Nothing +g4 = Pitch G 4 Nothing +a4 = Pitch A 4 Nothing +b4 = Pitch B 4 Nothing +cb4 = flat c4 +db4 = flat d4 +eb4 = flat e4 +fb4 = flat f4 +gb4 = flat g4 +ab4 = flat a4 +bb4 = flat b4 +cs4 = sharp c4 +ds4 = sharp d4 +es4 = sharp e4 +fs4 = sharp f4 +gs4 = sharp g4 +as4 = sharp a4 +bs4 = sharp b4 + +-- | Octave 5. +cb5, c5, cs5, db5, d5, ds5, eb5, e5, es5, fb5, f5, fs5, gb5, g5, gs5, ab5, a5, as5, bb5, b5, bs5 :: Pitch +c5 = Pitch C 5 Nothing +d5 = Pitch D 5 Nothing +e5 = Pitch E 5 Nothing +f5 = Pitch F 5 Nothing +g5 = Pitch G 5 Nothing +a5 = Pitch A 5 Nothing +b5 = Pitch B 5 Nothing +cb5 = flat c5 +db5 = flat d5 +eb5 = flat e5 +fb5 = flat f5 +gb5 = flat g5 +ab5 = flat a5 +bb5 = flat b5 +cs5 = sharp c5 +ds5 = sharp d5 +es5 = sharp e5 +fs5 = sharp f5 +gs5 = sharp g5 +as5 = sharp a5 +bs5 = sharp b5 + +-- | Octave 6. +cb6, c6, cs6, db6, d6, ds6, eb6, e6, es6, fb6, f6, fs6, gb6, g6, gs6, ab6, a6, as6, bb6, b6, bs6 :: Pitch +c6 = Pitch C 6 Nothing +d6 = Pitch D 6 Nothing +e6 = Pitch E 6 Nothing +f6 = Pitch F 6 Nothing +g6 = Pitch G 6 Nothing +a6 = Pitch A 6 Nothing +b6 = Pitch B 6 Nothing +cb6 = flat c6 +db6 = flat d6 +eb6 = flat e6 +fb6 = flat f6 +gb6 = flat g6 +ab6 = flat a6 +bb6 = flat b6 +cs6 = sharp c6 +ds6 = sharp d6 +es6 = sharp e6 +fs6 = sharp f6 +gs6 = sharp g6 +as6 = sharp a6 +bs6 = sharp b6 + +-- | Octave 7. +cb7, c7, cs7, db7, d7, ds7, eb7, e7, es7, fb7, f7, fs7, gb7, g7, gs7, ab7, a7, as7, bb7, b7, bs7 :: Pitch +c7 = Pitch C 7 Nothing +d7 = Pitch D 7 Nothing +e7 = Pitch E 7 Nothing +f7 = Pitch F 7 Nothing +g7 = Pitch G 7 Nothing +a7 = Pitch A 7 Nothing +b7 = Pitch B 7 Nothing +cb7 = flat c7 +db7 = flat d7 +eb7 = flat e7 +fb7 = flat f7 +gb7 = flat g7 +ab7 = flat a7 +bb7 = flat b7 +cs7 = sharp c7 +ds7 = sharp d7 +es7 = sharp e7 +fs7 = sharp f7 +gs7 = sharp g7 +as7 = sharp a7 +bs7 = sharp b7 + +-- | Octave 8. +cb8, c8, cs8, db8, d8, ds8, eb8, e8, es8, fb8, f8, fs8, gb8, g8, gs8, ab8, a8, as8, bb8, b8, bs8 :: Pitch +c8 = Pitch C 8 Nothing +d8 = Pitch D 8 Nothing +e8 = Pitch E 8 Nothing +f8 = Pitch F 8 Nothing +g8 = Pitch G 8 Nothing +a8 = Pitch A 8 Nothing +b8 = Pitch B 8 Nothing +cb8 = flat c8 +db8 = flat d8 +eb8 = flat e8 +fb8 = flat f8 +gb8 = flat g8 +ab8 = flat a8 +bb8 = flat b8 +cs8 = sharp c8 +ds8 = sharp d8 +es8 = sharp e8 +fs8 = sharp f8 +gs8 = sharp g8 +as8 = sharp a8 +bs8 = sharp b8 diff --git a/src/Herald/Sound.hs b/src/Herald/Sound.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Sound.hs @@ -0,0 +1,141 @@ +-- | Mono signals sampled at 'sampleRate', and stereo. +module Herald.Sound + ( Seconds, + Hz, + Sample, + Sound, + sampleRate, + sampleCount, + silence, + sine, + pluck, + harmonics, + inharmonics, + gain, + mixSound, + balanceSound, + Pan, + Stereo (..), + panSound, + balanceStereo, + ) +where + +import Control.Monad (forM_) +import Data.Vector.Unboxed (Vector) +import Data.Vector.Unboxed qualified as V +import Data.Vector.Unboxed.Mutable qualified as MV + +-- | A duration in seconds. +type Seconds = Double + +-- | A frequency in hertz. +type Hz = Double + +-- | An audio sample. +type Sample = Double + +-- | A mono signal. +type Sound = Vector Sample + +-- | Samples per second. +sampleRate :: Double +sampleRate = 48000.0 + +-- | Samples in a duration. +sampleCount :: Seconds -> Int +sampleCount t = round (sampleRate * t) + +-- | Silence. +silence :: Seconds -> Sound +silence t = V.replicate (sampleCount t) 0 + +-- | A sine wave. +sine :: Hz -> Seconds -> Sound +sine f t = V.generate (sampleCount t) (\i -> sin (fromIntegral i * step)) + where + step = (f * 2 * pi) / sampleRate + +-- | Deterministic white noise in @[-1, 1)@ from a linear congruential +-- generator. +noise :: Int -> [Sample] +noise = map unit . drop 1 . iterate step + where + step x = (1103515245 * x + 12345) `mod` 2147483648 + unit x = fromIntegral x / 1073741824 - 1 + +-- | Karplus-Strong plucked string. @decay@ is the gain per period. +pluck :: Double -> Hz -> Seconds -> Sound +pluck decay f t = V.create $ do + out <- MV.new len + forM_ (zip [0 .. len - 1] excitation) (uncurry (MV.write out)) + let go j averaged' allpassed' + | n + j >= len = pure () + | otherwise = do + x <- MV.read out j + y <- MV.read out (j + 1) + let averaged = decay * (x + y) / 2 + allpassed = c * averaged + averaged' - c * allpassed' + MV.write out (n + j) allpassed + go (j + 1) averaged allpassed + go 0 0 0 + pure out + where + len = sampleCount t + -- The loop is n samples of delay line, minus half a sample from the + -- averaging filter, plus a fractional delay d from a first-order all-pass + -- (Jaffe & Smith), so that its total length is exactly one period. + period = sampleRate / f + n = max 2 (floor (period + 0.4)) + d = period + 0.5 - fromIntegral n + c = (1 - d) / (1 + d) + burst = take n (noise (round f)) + mean = sum burst / fromIntegral n + peak = maximum [abs (x - mean) | x <- burst] + excitation = [(x - mean) / peak | x <- burst] + +-- | Integer multiples of a frequency. +harmonics :: Hz -> [Hz] +harmonics f = (* f) <$> [1 ..] + +-- | Harmonics stretched as in stiff strings: @n f sqrt (1 + b n^2)@. +inharmonics :: Double -> Hz -> [Hz] +inharmonics b f = zipWith stretch [1 ..] (harmonics f) + where + stretch n h = h * sqrt (1 + b * n ** 2) + +-- | Scale every sample. +gain :: Double -> Sound -> Sound +gain g = V.map (* g) + +-- | Sums sample by sample, padding shorter sounds with silence. +mixSound :: [Sound] -> Sound +mixSound xs = foldl add (V.replicate len 0) xs + where + len = maximum (0 : map V.length xs) + add acc s = V.imap (\i a -> a + if i < V.length s then V.unsafeIndex s i else 0) acc + +-- | Mixes dividing by the square root of the count, to keep the loudness of +-- a single sound. +balanceSound :: [Sound] -> Sound +balanceSound xs = gain (1 / sqrt (fromIntegral (max 1 (length xs)))) (mixSound xs) + +-- | From -1 (left) to 1 (right). +type Pan = Double + +-- | A left and a right channel. +data Stereo = Stereo + { leftChannel :: Sound, + rightChannel :: Sound + } + deriving (Show, Eq) + +-- | Constant-power pan law: equally loud at any position. +panSound :: Pan -> Sound -> Stereo +panSound p s = Stereo (gain (cos theta) s) (gain (sin theta) s) + where + theta = (max (-1) (min 1 p) + 1) * pi / 4 + +-- | 'balanceSound' for each channel. +balanceStereo :: [Stereo] -> Stereo +balanceStereo xs = Stereo (balanceSound (map leftChannel xs)) (balanceSound (map rightChannel xs)) diff --git a/src/Herald/Sound/IO.hs b/src/Herald/Sound/IO.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Sound/IO.hs @@ -0,0 +1,80 @@ +-- | 16-bit PCM WAV output, and playback through @ffplay@. +module Herald.Sound.IO + ( Audio (..), + encodeWav, + saveWav, + play, + ) +where + +import Control.Exception +import Control.Monad +import Data.ByteString.Builder qualified as BB +import Data.ByteString.Lazy qualified as B +import Data.Int +import Data.Vector.Unboxed qualified as V +import Data.Word +import GHC.IO.Exception (IOErrorType (..), IOException (..)) +import Herald.Sound +import System.Exit +import System.IO (hClose) +import System.Process + +-- | Mono or stereo audio. +class Audio a where + channels :: a -> [Sound] + +instance Audio (V.Vector Double) where + channels s = [s] + +instance Audio Stereo where + channels s = [leftChannel s, rightChannel s] + +-- | Samples outside @[-1, 1]@ are clipped. +encodeWav :: (Audio a) => a -> B.ByteString +encodeWav audio = BB.toLazyByteString (header <> samples) + where + chs = channels audio + n = length chs + frames = maximum (0 : map V.length chs) + sample s i = if i < V.length s then V.unsafeIndex s i else 0 + samples = foldr (\i b -> foldr (\s b' -> BB.int16LE (pcm (sample s i)) <> b') b chs) mempty [0 .. frames - 1] + rate = round sampleRate :: Word32 + blockAlign = fromIntegral (2 * n) :: Word16 + dataSize = fromIntegral (2 * n * frames) :: Word32 + header = + mconcat + [ BB.string7 "RIFF", + BB.word32LE (36 + dataSize), + BB.string7 "WAVE", + BB.string7 "fmt ", + BB.word32LE 16, -- fmt chunk size + BB.word16LE 1, -- PCM + BB.word16LE (fromIntegral n), -- channels + BB.word32LE rate, + BB.word32LE (rate * fromIntegral blockAlign), -- byte rate + BB.word16LE blockAlign, + BB.word16LE 16, -- bits per sample + BB.string7 "data", + BB.word32LE dataSize + ] + pcm x = round (32767 * max (-1) (min 1 x)) :: Int16 + +-- | Write a WAV file. +saveWav :: (Audio a) => FilePath -> a -> IO () +saveWav filePath = B.writeFile filePath . encodeWav + +-- | Requires @ffplay@ on the @PATH@. +play :: (Audio a) => a -> IO () +play audio = do + let args = ["-autoexit", "-showmode", "1", "-"] + withCreateProcess (proc "ffplay" args) {std_in = CreatePipe} $ \stdin' _ _ ph -> do + -- ffplay closes the pipe early if the user quits; that's not an error. + forM_ stdin' $ \h -> ignoreBrokenPipe $ B.hPut h (encodeWav audio) >> hClose h + code <- waitForProcess ph + case code of + ExitSuccess -> pure () + ExitFailure c -> ioError . userError $ "ffplay exited with code " ++ show c + where + ignoreBrokenPipe = handle $ \e -> + unless (ioe_type e == ResourceVanished) (throwIO e) diff --git a/src/Herald/Tuning.hs b/src/Herald/Tuning.hs new file mode 100644 --- /dev/null +++ b/src/Herald/Tuning.hs @@ -0,0 +1,44 @@ +-- | Frequencies of pitches: equal temperament and historical temperaments. +module Herald.Tuning + ( Tuning (..), + a440, + equalTemperament, + temperament, + werckmeisterIII, + quarterCommaMeantone, + ) +where + +import Data.Map.Strict qualified as Map +import Herald.Score.Pitch (Semitones) +import Herald.Sound (Hz) + +-- | Semitones are relative to A4. +newtype Tuning = Tuning {tune :: Semitones -> Hz} + +-- | Equal temperament at 440 Hz. +a440 :: Tuning +a440 = equalTemperament 440 + +-- | Takes the frequency of A4. +equalTemperament :: Hz -> Tuning +equalTemperament ref = Tuning $ \n -> ref * 2 ** (fromIntegral n / 12) + +-- | Deviations from equal temperament in cents for each pitch class from C +-- to B, anchored at the frequency of A4. +temperament :: [Double] -> Hz -> Tuning +temperament cents ref = Tuning $ \n -> + ref * 2 ** ((fromIntegral n + (offset (n + 9) - offset 9) / 100) / 12) + where + deviations = Map.fromList (zip [0 .. 11] cents) + offset n = Map.findWithDefault 0 (n `mod` 12) deviations + +-- | Werckmeister III well temperament. +werckmeisterIII :: Hz -> Tuning +werckmeisterIII = + temperament [0, -9.775, -7.82, -5.865, -9.775, -1.955, -11.73, -3.91, -7.82, -11.73, -3.91, -7.82] + +-- | Quarter-comma meantone. +quarterCommaMeantone :: Hz -> Tuning +quarterCommaMeantone = + temperament [0, -24.0, -6.8, 10.3, -13.7, 3.4, -20.5, -3.4, -27.4, -10.3, 6.8, -17.1] diff --git a/test/Main.hs b/test/Main.hs new file mode 100644 --- /dev/null +++ b/test/Main.hs @@ -0,0 +1,246 @@ +module Main (main) where + +import Data.ByteString.Lazy qualified as B +import Data.ByteString.Lazy.Char8 qualified as BC +import Data.Vector.Unboxed qualified as V +import Herald +import Test.Tasty +import Test.Tasty.HUnit + +main :: IO () +main = + defaultMain $ + testGroup + "herald" + [ pitchTests, + tuningTests, + soundTests, + instrumentTests, + scoreTests, + tieTests, + meterTests, + stereoTests, + wavTests + ] + +pitchTests :: TestTree +pitchTests = + testGroup + "Pitch" + [ testCase "A4 is the reference" $ pitchSemitones cMajor a4 @?= 0, + testCase "middle C is 9 semitones below A4" $ pitchSemitones cMajor c4 @?= -9, + testCase "octaves are 12 semitones apart" $ pitchSemitones cMajor a5 @?= 12, + testCase "names carry accidentals" $ do + pitchSemitones cMajor fs4 @?= pitchSemitones cMajor (sharp f4) + pitchSemitones cMajor bb4 @?= pitchSemitones cMajor a4 + 1, + testCase "unwritten accidentals come from the key" $ + pitchSemitones gMinor b4 @?= pitchSemitones cMajor bb4, + testCase "a natural sign cancels the key" $ + pitchSemitones gMinor (natural b4) @?= pitchSemitones cMajor b4, + testCase "key signatures add accidentals in order" $ do + map (keyAccidental (sharps 2)) [F, C, G] @?= [Sharp, Sharp, Natural] + map (keyAccidental (flats 2)) [B, E, A] @?= [Flat, Flat, Natural] + ] + +tuningTests :: TestTree +tuningTests = + testGroup + "Tuning" + [ testCase "A4 is 440 Hz" $ tune a440 0 @?= 440, + testCase "an octave doubles the frequency" $ tune a440 12 @?= 880, + testCase "equal temperament takes a reference pitch" $ tune (equalTemperament 415) 0 @?= 415, + testCase "temperaments are anchored at A4" $ do + tune (werckmeisterIII 440) 0 @?= 440 + tune (quarterCommaMeantone 440) 0 @?= 440, + testCase "Werckmeister III raises C4 by its offset from A" $ + assertApprox "cents" 11.73 (cents (tune (werckmeisterIII 440) (-9)) (tune a440 (-9))), + testCase "quarter-comma meantone has a pure major third on C" $ + assertApprox "cents" (cents 5 4) (cents (tune meantone (-5)) (tune meantone (-9))), + testCase "the score uses the configured tuning" $ + playScoreMono defaultConfig {tuning = equalTemperament 220} [(defaultVoice, tellNote quarter a5)] + @?= Right (render (tellNote quarter a4)) + ] + where + meantone = quarterCommaMeantone 440 + cents x y = 1200 * logBase 2 (x / y) + assertApprox msg expected actual = + assertBool (msg ++ ": expected " ++ show expected ++ ", got " ++ show actual) (abs (expected - actual) < 0.1) + +soundTests :: TestTree +soundTests = + testGroup + "Sound" + [ testCase "durations round to whole samples" $ do + V.length (silence 1) @?= 48000 + V.length (sine 440 0.5) @?= 24000, + testCase "mixing pads shorter sounds with silence" $ + mixSound [V.fromList [1, 2, 3], V.fromList [10]] @?= V.fromList [11, 2, 3], + testCase "balanced mixing divides by the square root of the count" $ + balanceSound [V.fromList [1], V.fromList [1], V.fromList [1], V.fromList [1]] @?= V.fromList [2], + testCase "a pluck starts at a peak of 1 and decays" $ do + let s = pluck 0.996 220 1 + V.length s @?= 48000 + peak s @?= 1 + assertBool "doesn't decay" (peak (V.drop 40000 s) < 0.5) + ] + +instrumentTests :: TestTree +instrumentTests = + testGroup "Instrument" . concat $ + [ [ testCase ("notes last exactly their duration: " ++ name) $ + V.length (renderNote i 440 0.3) @?= 14400 + | (name, i) <- instruments + ], + [ testCase ("notes peak at most 1: " ++ name ++ " at " ++ show f ++ " Hz") $ + assertBool "too loud" (peak (renderNote i f 0.5) <= 1) + | (name, i) <- instruments, + f <- [110, 440, 1760] + ], + [ testCase "a trill fills its duration" $ + V.length (trill additive 6 440 494 0.75) @?= 36000, + testCase "a chord is as long as its notes" $ + V.length (chord organ [262, 330, 392] 0.5) @?= 24000 + ] + ] + where + instruments = [("pure tone", pureTone), ("additive", additive), ("organ", organ), ("harpsichord", harpsichord)] + +scoreTests :: TestTree +scoreTests = + testGroup + "Score" + [ testCase "a quarter note at 120 bpm lasts half a second" $ + V.length (render (tellNotes quarter [c4, d4])) @?= 48000, + testCase "rests and notes share the timeline" $ + V.length (render (tellRest half >> tellNote eighth c4)) @?= 60000, + testCase "the tempo comes from the configuration" $ + V.length <$> playScoreMono defaultConfig {tempo = 60} [(defaultVoice, tellNote quarter c4)] @?= Right 48000, + testCase "voices start in C major and setKey applies from then on" $ + render (tellNote quarter b4 >> setKey gMinor >> tellNote quarter b4) + @?= render (tellNotes quarter [natural b4, bb4]), + testCase "an accidental lasts until the end of the bar" $ + render (tellNote quarter (sharp f4) >> tellNote quarter f4) + @?= render (tellNotes quarter [fs4, fs4]), + testCase "a bar line cancels earlier accidentals" $ + render (tellNote quarter (sharp f4) >> tellBar >> tellNote quarter f4) + @?= render (tellNotes quarter [fs4, natural f4]), + testCase "a trill's auxiliary accidental doesn't carry on" $ + render (tellTrill quarter 4 e4 (sharp f4) >> tellNote quarter f4) + @?= render (tellTrill quarter 4 e4 fs4 >> tellNote quarter (natural f4)), + testCase "voices are rendered independently" $ + playScoreMono defaultConfig [(defaultVoice, tellNote quarter (sharp f4)), (defaultVoice, tellNote quarter f4)] + @?= playScoreMono defaultConfig [(defaultVoice, tellNote quarter fs4), (defaultVoice, tellNote quarter (natural f4))], + testCase "each voice plays its own instrument" $ + playScoreMono defaultConfig [(defaultVoice {instrument = organ}, tellNote quarter c4), (defaultVoice, tellNote quarter c4)] + @?= Right (balanceSound [renderNote organ (tune a440 (-9)) 0.5, renderNote additive (tune a440 (-9)) 0.5]), + testCase "dynamics scale notes from then on" $ + render (setDynamic forte >> tellNote quarter c4) + @?= gain (dynamicGain forte) (render (tellNote quarter c4)), + testCase "dynamics go from soft to loud" + $ assertBool "out of order" + $ and (zipWith (<) dynamics (drop 1 dynamics)) + ] + where + dynamics = [pianissimo, piano, mezzoPiano, mezzoForte, forte, fortissimo] + +tieTests :: TestTree +tieTests = + testGroup + "Tie" + [ testCase "tied notes sound as one" $ + render (tellTie quarter c4 >> tellNote quarter c4) @?= render (tellNote half c4), + testCase "ties can be chained" $ + render (tellTie eighth c4 >> tellTie eighth c4 >> tellNote quarter c4) + @?= render (tellNote half c4), + testCase "a tied note keeps its accidental across the bar line" $ + render (tellTie quarter (sharp f4) >> tellBar >> tellNote quarter f4) + @?= render (tellNote half fs4), + testCase "a tie into a different pitch is an error" $ + result [tellTie quarter c4 >> tellNote quarter d4] + @?= Left (ScoreError 1 1 TieToDifferentPitch), + testCase "a tie followed by a rest is an error" $ + result [tellTie quarter c4 >> tellBar >> tellRest quarter] + @?= Left (ScoreError 1 2 UnfinishedTie), + testCase "a voice can't end in a tie" $ + result [tellTie quarter c4] @?= Left (ScoreError 1 1 UnfinishedTie) + ] + +meterTests :: TestTree +meterTests = + testGroup + "Meter" + [ testCase "a bar lasts its time signature in beats" $ do + meterBeats (Meter 4 4) @?= 4 + meterBeats (Meter 6 8) @?= 3, + testCase "bars that add up are accepted" $ + result [setMeter (Meter 3 4) >> tellNotes quarter [c4, d4, e4] >> tellBar >> tellNote (dotted half) c4] + @?= Right (), + testCase "a short bar is an error" $ + result [setMeter (Meter 4 4) >> tellNotes quarter [c4, d4, e4] >> tellBar] + @?= Left (ScoreError 1 1 (WrongBarLength 3 4)), + testCase "the last bar is checked too" $ + result [setMeter (Meter 2 4) >> tellNotes quarter [c4, d4] >> tellBar >> tellNote quarter c4] + @?= Left (ScoreError 1 2 (WrongBarLength 1 2)), + testCase "a tie counts in each bar it crosses" $ + result [setMeter (Meter 2 4) >> tellNote quarter c4 >> tellTie quarter d4 >> tellBar >> tellNotes quarter [d4, e4]] + @?= Right (), + testCase "errors name the voice" $ + result [tellNote quarter c4, setMeter (Meter 2 4) >> tellNote quarter c4] + @?= Left (ScoreError 2 1 (WrongBarLength 1 2)) + ] + +stereoTests :: TestTree +stereoTests = + testGroup + "Stereo" + [ testCase "the centre splits a sound at equal power" $ do + let Stereo l r = panSound 0 (V.fromList [1]) + assertClose l (V.fromList [sqrt 0.5]) + assertClose r (V.fromList [sqrt 0.5]), + testCase "hard left and right use a single channel" $ do + assertClose (rightChannel (panSound (-1) (V.fromList [1]))) (V.fromList [0]) + assertClose (leftChannel (panSound 1 (V.fromList [1]))) (V.fromList [0]), + testCase "voices go to their side" $ do + let left = tellNote quarter c4 + right = tellNote quarter e4 + case playScoreStereo defaultConfig [(defaultVoice {pan = -1}, left), (defaultVoice {pan = 1}, right)] of + Left err -> assertFailure (displayScoreError err) + Right (Stereo l r) -> do + assertClose l (gain (1 / sqrt 2) (render left)) + assertClose r (gain (1 / sqrt 2) (render right)) + ] + where + assertClose x y = do + V.length x @?= V.length y + assertBool "channels differ" (V.and (V.zipWith (\a b -> abs (a - b) < 1e-12) x y)) + +wavTests :: TestTree +wavTests = + testGroup + "WAV" + [ testCase "header and 16-bit samples" $ do + let wav = encodeWav (mono [0, 1, -1]) + B.length wav @?= 44 + 6 + BC.take 4 wav @?= BC.pack "RIFF" + BC.take 4 (B.drop 8 wav) @?= BC.pack "WAVE" + B.unpack (B.drop 44 wav) @?= [0, 0, 0xff, 0x7f, 0x01, 0x80], + testCase "out-of-range samples are clipped" $ + B.drop 44 (encodeWav (mono [2, -2])) @?= B.drop 44 (encodeWav (mono [1, -1])), + testCase "stereo interleaves left and right" $ do + let wav = encodeWav (Stereo (V.fromList [1, 0]) (V.fromList [-1])) + B.length wav @?= 44 + 8 + B.unpack (B.take 2 (B.drop 22 wav)) @?= [2, 0] + B.unpack (B.drop 44 wav) @?= [0xff, 0x7f, 0x01, 0x80, 0, 0, 0, 0] + ] + +render :: Performance () -> Sound +render v = either (error . displayScoreError) id (playScoreMono defaultConfig [(defaultVoice, v)]) + +result :: [Performance ()] -> Either ScoreError () +result vs = () <$ playScoreMono defaultConfig [(defaultVoice, v) | v <- vs] + +peak :: Sound -> Double +peak = V.maximum . V.map abs + +mono :: [Double] -> Sound +mono = V.fromList