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See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +Also add information on how to contact you by electronic and paper mail. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the library, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the + library `Frob' (a library for tweaking knobs) written by James Random Hacker. + + , 1 April 1990 + Ty Coon, President of Vice + +That's all there is to it! + diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/conduit-audio-samplerate.cabal b/conduit-audio-samplerate.cabal new file mode 100644 --- /dev/null +++ b/conduit-audio-samplerate.cabal @@ -0,0 +1,41 @@ +name: conduit-audio-samplerate +version: 0.1 +author: Michael Tolly +maintainer: miketolly@gmail.com +license: LGPL +license-file: LICENSE +category: Sound +build-type: Simple +cabal-version: >= 1.10 +homepage: http://github.com/mtolly/conduit-audio +bug-reports: http://github.com/mtolly/conduit-audio/issues +synopsis: conduit-audio interface to the libsamplerate resampling library +description: + A binding to the @libsamplerate@ library for use with @conduit-audio@, + to resample audio streams. + . + Requires the @libsamplerate@ library. + On Ubuntu, @apt-get install libsamplerate0-dev@; + on Mac with Homebrew, @brew install libsamplerate@. + +library + exposed-modules: + Data.Conduit.Audio.SampleRate + other-modules: + Data.Conduit.Audio.SampleRate.Binding + build-depends: + base >= 4.6 && < 4.8 + , conduit + , conduit-audio >= 0.1 && < 0.2 + , resourcet + , transformers >= 0.3 && < 0.5 + , vector + hs-source-dirs: src + default-language: Haskell2010 + ghc-options: -Wall -O2 + extra-libraries: + samplerate + +source-repository head + type: git + location: http://github.com/mtolly/conduit-audio diff --git a/src/Data/Conduit/Audio/SampleRate.hs b/src/Data/Conduit/Audio/SampleRate.hs new file mode 100644 --- /dev/null +++ b/src/Data/Conduit/Audio/SampleRate.hs @@ -0,0 +1,79 @@ +{- | +Uses @libsamplerate@ to resample a stream of audio. +-} +module Data.Conduit.Audio.SampleRate +( resample, resampleTo +, SRC.ConverterType(..), SRC.SRCError(..) +) where + +import Data.Conduit.Audio +import qualified Data.Conduit.Audio.SampleRate.Binding as SRC +import Control.Monad.IO.Class (liftIO) +import qualified Data.Vector.Storable as V +import qualified Data.Conduit as C +import Control.Monad.Fix (fix) +import Control.Monad (when) +import Foreign +import Control.Monad.Trans.Resource (MonadResource) + +resample + :: (MonadResource m) + => Double -- ^ the ratio of new sample rate to old sample rate + -> SRC.ConverterType + -> AudioSource m Float + -> AudioSource m Float +resample rat ctype src = resampleTo (rat * rate src) ctype src + +resampleTo + :: (MonadResource m) + => Rate -- ^ the new sample rate + -> SRC.ConverterType + -> AudioSource m Float + -> AudioSource m Float +resampleTo r' ctype (AudioSource s r c l) = let + rat = r' / r + l' = round $ fromIntegral l * rat + s' = s C.=$= C.bracketP + (SRC.new ctype c) + SRC.delete + (\lsr -> fix $ \loop -> C.await >>= \mx -> case mx of + Nothing -> return () + Just v -> do + isEnd <- C.await >>= \my -> case my of + Nothing -> return True + Just v' -> do + C.leftover v' + return False + let inLen = vectorFrames v c + outLen = round $ fromIntegral inLen * rat * 1.1 + outPtr <- liftIO $ mallocArray $ outLen * c + dout <- liftIO $ V.unsafeWith v $ \inPtr -> do + SRC.process lsr $ SRC.DataIn + { SRC.data_in = castPtr inPtr + , SRC.data_out = castPtr outPtr + , SRC.input_frames = fromIntegral inLen + , SRC.output_frames = fromIntegral outLen + , SRC.src_ratio = rat + , SRC.end_of_input = isEnd + } + outFP <- liftIO $ newForeignPtr finalizerFree outPtr + let v' = V.unsafeFromForeignPtr0 outFP $ + fromIntegral (SRC.output_frames_gen dout) * c + when (V.length v' /= 0) $ C.yield v' + let inUsed = fromIntegral $ SRC.input_frames_used dout + when (inUsed /= inLen) $ + -- we want to make sure we don't keep giving SRC too small a chunk forever + if SRC.output_frames_gen dout /= 0 + then C.leftover $ V.drop (inUsed * c) v + -- SRC did produce some output this time, so we're fine + else C.await >>= \mz -> case mz of + Nothing -> return () + -- this should never happen, right? + -- that would mean v was the last chunk, we told SRC it was the + -- last chunk, but then it didn't use it all + Just v'' -> C.leftover $ V.drop (inUsed * c) v V.++ v'' + -- if v was too small to produce anything, + -- glue it onto v' to make a bigger chunk + loop + ) + in AudioSource s' r' c l' diff --git a/src/Data/Conduit/Audio/SampleRate/Binding.chs b/src/Data/Conduit/Audio/SampleRate/Binding.chs new file mode 100644 --- /dev/null +++ b/src/Data/Conduit/Audio/SampleRate/Binding.chs @@ -0,0 +1,152 @@ +{- | +A binding to the of @libsamplerate@. +Errors are turned into Haskell exceptions of type 'SRCError'. +The @SRC_DATA@ struct is split into two Haskell types +for the input ('DataIn') and output ('DataOut') parts. +-} +{-# LANGUAGE DeriveDataTypeable #-} +module Data.Conduit.Audio.SampleRate.Binding +( new, delete, process, reset, setRatio +, State, DataIn(..), DataOut(..), ConverterType(..), SRCError(..) +) where + +import Foreign hiding (new) +import Foreign.C +import Control.Monad (when) +import Control.Applicative +import Data.Typeable (Typeable) +import Control.Exception (Exception, throwIO) + +#include + +inThisModule :: String -> String +inThisModule = ("Data.Conduit.Audio.SampleRate.Binding." ++) + +{#pointer *SRC_STATE as State newtype #} +{#pointer *SRC_DATA as Data newtype #} + +{#context prefix="src_"#} + +-- SRC_STATE* src_new (int converter_type, int channels, int *error) ; +{#fun new as newRaw + { convTypeToC `ConverterType' + , `Int' + , id `Ptr CInt' + } -> `State' #} + +-- SRC_STATE* src_delete (SRC_STATE *state) ; +{#fun delete as deleteRaw + { `State' + } -> `State' #} + +-- int src_process (SRC_STATE *state, SRC_DATA *data) ; +{#fun process as processRaw + { `State' + , `Data' + } -> `Int' #} + +-- int src_reset (SRC_STATE *state) ; +{#fun reset as resetRaw + { `State' + } -> `Int' #} + +-- int src_set_ratio (SRC_STATE *state, double new_ratio) ; +{#fun set_ratio as setRatioRaw + { `State' + , `Double' + } -> `Int' #} + +{#enum define ConverterType + { SRC_SINC_BEST_QUALITY as SincBestQuality + , SRC_SINC_MEDIUM_QUALITY as SincMediumQuality + , SRC_SINC_FASTEST as SincFastest + , SRC_ZERO_ORDER_HOLD as ZeroOrderHold + , SRC_LINEAR as Linear + } deriving (Eq, Ord, Show, Read, Bounded) #} + +convTypeToC :: ConverterType -> CInt +convTypeToC = fromIntegral . fromEnum + +-- const char* src_strerror (int error) ; +{#fun strerror as ^ + { id `CInt' + } -> `CString' id #} + +sampleRateError :: (Integral i) => String -> i -> IO () +sampleRateError _ 0 = return () +sampleRateError fn i = do + ps <- strerror $ fromIntegral i + s <- if ps == nullPtr + then return "strerror returned NULL" + else peekCString ps + throwIO $ SRCError (inThisModule fn) (fromIntegral i) s + +-- | @libsamplerate@ functions may throw this as an exception. +-- Contains the function that caused the error, the numeric error code, +-- and a human-readable message. +data SRCError = SRCError String Int String + deriving (Eq, Ord, Show, Read, Typeable) + +instance Exception SRCError + +new + :: ConverterType + -> Int -- ^ channels + -> IO State +new ctype chans = alloca $ \perr -> do + state@(State pstate) <- newRaw ctype chans perr + when (pstate == nullPtr) $ peek perr >>= sampleRateError "new" + return state + +{- +typedef struct +{ float *data_in, *data_out ; + + long input_frames, output_frames ; + long input_frames_used, output_frames_gen ; + + int end_of_input ; + + double src_ratio ; +} SRC_DATA ; +-} + +data DataIn = DataIn + { data_in :: Ptr CFloat + , data_out :: Ptr CFloat + , input_frames :: Integer + , output_frames :: Integer + , src_ratio :: Double + , end_of_input :: Bool + } deriving (Eq, Ord, Show) + +data DataOut = DataOut + { input_frames_used :: Integer + , output_frames_gen :: Integer + } deriving (Eq, Ord, Show) + +process :: State -> DataIn -> IO DataOut +process state input = allocaBytes {#sizeof SRC_DATA#} $ \pdata -> do + let sdata = Data pdata + {#set SRC_DATA.data_in #} sdata $ data_in input + {#set SRC_DATA.data_out #} sdata $ data_out input + {#set SRC_DATA.input_frames #} sdata $ fromIntegral $ input_frames input + {#set SRC_DATA.output_frames #} sdata $ fromIntegral $ output_frames input + {#set SRC_DATA.src_ratio #} sdata $ realToFrac $ src_ratio input + {#set SRC_DATA.end_of_input #} sdata $ fromBool $ end_of_input input + processRaw state sdata >>= sampleRateError "process" + DataOut + <$> fmap fromIntegral ({#get SRC_DATA.input_frames_used #} sdata) + <*> fmap fromIntegral ({#get SRC_DATA.output_frames_gen #} sdata) + +delete :: State -> IO () +delete state = do + State p <- deleteRaw state + when (p /= nullPtr) $ throwIO $ + SRCError (inThisModule "delete") 0 "delete returned non-null pointer" + +reset :: State -> IO () +reset state = resetRaw state >>= sampleRateError "reset" + +setRatio :: State -> Double -> IO () +setRatio state r = setRatioRaw state r >>= sampleRateError "setRatio"