From: PHO Date: Sun, 9 Jan 2011 03:09:19 +0000 (+0900) Subject: DecorrSamples X-Git-Url: https://git.cielonegro.org/gitweb.cgi?a=commitdiff_plain;h=78a686c2314abc67b3f388833c255a102fe63024;p=wavpack.git DecorrSamples --- diff --git a/Codec/Audio/WavPack/Internal.hs b/Codec/Audio/WavPack/Internal.hs new file mode 100644 index 0000000..b852a76 --- /dev/null +++ b/Codec/Audio/WavPack/Internal.hs @@ -0,0 +1,196 @@ +{-# LANGUAGE + BangPatterns + , UnicodeSyntax + #-} +-- | WavPack internal functions +module Codec.Audio.WavPack.Internal + ( packWeight + , unpackWeight + + , log2s + , log2 + + , exp2s + , exp2 + ) + where +import Data.Int +import Data.Word +import Data.Bits +import qualified Data.Vector.Unboxed as UV +import Prelude.Unicode + +-- | Convert internal weights (which are normally +/-1024) to an 8-bit +-- signed character version for storage in metadata. The weights are +-- clipped here in the case they are outside that range. +packWeight ∷ Int16 → Word8 +packWeight !w + = let !w' | w > 1024 = 1024 + | w < -1024 = -1024 + | otherwise = w + !w'' | w' > 0 = w' - ((w' + 64) `shiftR` 7) + | otherwise = w' + !w''' = (w'' + 4) `shiftR` 3 + in + fromIntegral w''' + +-- | Convert a packed weight to internal weight (+/-1024). Note that +-- the following equation might not hold because 'packWeight' is +-- lossy. +-- +-- > unpackWeight . packWeight = id +-- +unpackWeight ∷ Word8 → Int16 +unpackWeight !w + = let w' ∷ Int8 + w' = fromIntegral w + w'' ∷ Int16 + w'' = (fromIntegral w') `shiftL` 3 + !w''' | w'' > 0 = w'' + ((w'' + 64) `shiftR` 7) + | otherwise = w'' + in + w''' + +-- | Return the 'log2' for the specified 32-bit signed integer. All +-- input values are valid and the return values are in the range of +-- +/-8192. +log2s ∷ Int32 → Int16 +log2s !n + | n < 0 = fromIntegral $ negate $ log2 $ fromIntegral $ negate n + | otherwise = fromIntegral $ log2 $ fromIntegral n + +-- | The concept of a base 2 logarithm is used in many parts of +-- WavPack. It is a way of sufficiently accurately representing 32-bit +-- signed and unsigned values storing only 16 bits (actually +-- fewer). It is also used in the hybrid mode for quickly comparing +-- the relative magnitude of large values (i.e. division) and +-- providing smooth exponentials using only addition. +-- +-- These are not strict logarithms in that they become linear around +-- zero and can therefore represent both zero and negative +-- values. They have 8 bits of precision and in \"roundtrip\" +-- conversions the total error never exceeds 1 part in 225 except for +-- the cases of +/-115 and +/-195 (which error by 1). +-- +-- This function returns the log2 for the specified 32-bit unsigned +-- value. The maximum value allowed is about 0xff800000 and returns +-- 8447. +log2 ∷ Word32 → Word16 +log2 !n + | n' < (1 `shiftL` 8) + = let dbits ∷ Word16 + dbits = fromIntegral $ getNBits $ fromIntegral n' + !index = (n' `shiftL` fromIntegral (9 - dbits)) .&. 0xFF + !log2n = fromIntegral $ getLog2 $ fromIntegral index + in + (dbits `shiftL` 8) + log2n + | otherwise + = let dbits ∷ Word16 + dbits | n' < (1 `shiftL` 16) + = fromIntegral (getNBits $ fromIntegral $ n' `shiftR` 8) + 8 + | n' < (1 `shiftL` 24) + = fromIntegral (getNBits $ fromIntegral $ n' `shiftR` 16) + 16 + | otherwise + = fromIntegral (getNBits $ fromIntegral $ n' `shiftR` 24) + 24 + !index = (n' `shiftR` fromIntegral (dbits - 9)) .&. 0xFF + !log2n = fromIntegral $ getLog2 $ fromIntegral index + in + (dbits `shiftL` 8) + log2n + where + n' ∷ Word32 + n' = n + (n `shiftR` 9) + +-- | Return the original integer represented by the supplied logarithm +-- (at least within the provided accuracy). The log is signed, but +-- since a full 32-bit value is returned this can be used for unsigned +-- conversions as well (i.e. the input range is -8192 to +8447). +exp2s ∷ Int16 → Int32 +exp2s !l + | l < 0 = fromIntegral $ negate $ exp2 $ fromIntegral $ negate l + | otherwise = fromIntegral $ exp2 $ fromIntegral l + +-- | Return the original integer represented by the supplied logarithm +-- (at least within the provided accuracy). +exp2 ∷ Word16 → Word32 +exp2 !l + = let exp2l ∷ Word32 + exp2l = fromIntegral (getExp2 $ fromIntegral $ l .&. 0xFF) .|. 0x100 + l' ∷ Word32 + l' = fromIntegral $ l `shiftR` 8 + in + if l' ≤ 9 then + exp2l `shiftR` fromIntegral (9 - l') + else + exp2l `shiftL` fromIntegral (l' - 9) + +getNBits ∷ Word8 → Word8 +getNBits = UV.unsafeIndex nbitsTable ∘ fromIntegral + where + nbitsTable ∷ UV.Vector Word8 + nbitsTable + = UV.fromList + [ 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4 -- 0 - 15 + , 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 -- 16 - 31 + , 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6 -- 32 - 47 + , 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6 -- 48 - 63 + , 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 -- 64 - 79 + , 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 -- 80 - 95 + , 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 -- 96 - 111 + , 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 -- 112 - 127 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 128 - 143 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 144 - 159 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 160 - 175 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 176 - 191 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 192 - 207 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 208 - 223 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 224 - 239 + , 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 -- 240 - 255 + ] + +getLog2 ∷ Word8 → Word8 +getLog2 = UV.unsafeIndex log2Table ∘ fromIntegral + where + log2Table ∷ UV.Vector Word8 + log2Table + = UV.fromList + [ 0x00, 0x01, 0x03, 0x04, 0x06, 0x07, 0x09, 0x0a, 0x0B, 0x0D, 0x0E, 0x10, 0x11, 0x12, 0x14, 0x15 + , 0x16, 0x18, 0x19, 0x1a, 0x1C, 0x1D, 0x1E, 0x20, 0x21, 0x22, 0x24, 0x25, 0x26, 0x28, 0x29, 0x2a + , 0x2C, 0x2D, 0x2E, 0x2F, 0x31, 0x32, 0x33, 0x34, 0x36, 0x37, 0x38, 0x39, 0x3B, 0x3C, 0x3D, 0x3E + , 0x3F, 0x41, 0x42, 0x43, 0x44, 0x45, 0x47, 0x48, 0x49, 0x4a, 0x4B, 0x4D, 0x4E, 0x4F, 0x50, 0x51 + , 0x52, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63 + , 0x64, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x74, 0x75 + , 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85 + , 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95 + , 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9B, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4 + , 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xa9, 0xaa, 0xaB, 0xaC, 0xaD, 0xaE, 0xaF, 0xB0, 0xB1, 0xB2, 0xB2 + , 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xB9, 0xBa, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF, 0xC0, 0xC0 + , 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC6, 0xC7, 0xC8, 0xC9, 0xCa, 0xCB, 0xCB, 0xCC, 0xCD, 0xCE + , 0xCF, 0xD0, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD8, 0xD9, 0xDa, 0xDB + , 0xDC, 0xDC, 0xDD, 0xDE, 0xDF, 0xE0, 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE4, 0xE5, 0xE6, 0xE7, 0xE7 + , 0xE8, 0xE9, 0xEa, 0xEa, 0xEB, 0xEC, 0xED, 0xEE, 0xEE, 0xEF, 0xF0, 0xF1, 0xF1, 0xF2, 0xF3, 0xF4 + , 0xF4, 0xF5, 0xF6, 0xF7, 0xF7, 0xF8, 0xF9, 0xF9, 0xFa, 0xFB, 0xFC, 0xFC, 0xFD, 0xFE, 0xFF, 0xFF + ] + +getExp2 ∷ Word8 → Word8 +getExp2 = UV.unsafeIndex exp2Table ∘ fromIntegral + where + exp2Table ∷ UV.Vector Word8 + exp2Table + = UV.fromList + [ 0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0B + , 0x0B, 0x0C, 0x0D, 0x0E, 0x0E, 0x0F, 0x10, 0x10, 0x11, 0x12, 0x13, 0x13, 0x14, 0x15, 0x16, 0x16 + , 0x17, 0x18, 0x19, 0x19, 0x1a, 0x1B, 0x1C, 0x1D, 0x1D, 0x1E, 0x1F, 0x20, 0x20, 0x21, 0x22, 0x23 + , 0x24, 0x24, 0x25, 0x26, 0x27, 0x28, 0x28, 0x29, 0x2a, 0x2B, 0x2C, 0x2C, 0x2D, 0x2E, 0x2F, 0x30 + , 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3a, 0x3B, 0x3C, 0x3D + , 0x3E, 0x3F, 0x40, 0x41, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x48, 0x49, 0x4a, 0x4B + , 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 0x51, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a + , 0x5B, 0x5C, 0x5D, 0x5E, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69 + , 0x6a, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79 + , 0x7a, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87, 0x88, 0x89, 0x8a + , 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, 0x93, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9B + , 0x9C, 0x9D, 0x9F, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa8, 0xa9, 0xaa, 0xaB, 0xaC, 0xaD + , 0xaF, 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB6, 0xB7, 0xB8, 0xB9, 0xBa, 0xBC, 0xBD, 0xBE, 0xBF, 0xC0 + , 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC8, 0xC9, 0xCa, 0xCB, 0xCD, 0xCE, 0xCF, 0xD0, 0xD2, 0xD3, 0xD4 + , 0xD6, 0xD7, 0xD8, 0xD9, 0xDB, 0xDC, 0xDD, 0xDE, 0xE0, 0xE1, 0xE2, 0xE4, 0xE5, 0xE6, 0xE8, 0xE9 + , 0xEa, 0xEC, 0xED, 0xEE, 0xF0, 0xF1, 0xF2, 0xF4, 0xF5, 0xF6, 0xF8, 0xF9, 0xFa, 0xFC, 0xFD, 0xFF + ] diff --git a/Codec/Audio/WavPack/Metadata.hs b/Codec/Audio/WavPack/Metadata.hs index d8c0df1..00e1d02 100644 --- a/Codec/Audio/WavPack/Metadata.hs +++ b/Codec/Audio/WavPack/Metadata.hs @@ -11,11 +11,13 @@ module Codec.Audio.WavPack.Metadata , Dummy(..) , DecorrTerms(..) , DecorrWeights(..) + , DecorrSamples(..) , RIFFHeader(..) , RIFFTrailer(..) , Unknown(..) ) where +import Codec.Audio.WavPack.Internal import Control.Monad import Data.Binary import Data.Binary.Get @@ -94,6 +96,7 @@ instance Binary SubBlock where getSubBlock 0x00 = fmap SubBlock (get ∷ Get Dummy ) getSubBlock 0x02 = fmap SubBlock (get ∷ Get DecorrTerms ) getSubBlock 0x03 = fmap SubBlock (get ∷ Get DecorrWeights) + getSubBlock 0x04 = fmap SubBlock (get ∷ Get DecorrSamples) getSubBlock 0x21 = fmap SubBlock (get ∷ Get RIFFHeader ) getSubBlock 0x22 = fmap SubBlock (get ∷ Get RIFFTrailer ) getSubBlock unknownID @@ -177,35 +180,36 @@ instance Metadata DecorrWeights where metaSize = fromIntegral ∘ UV.length ∘ decwVec instance Binary DecorrWeights where - put = UV.mapM_ (putWord8 ∘ packW) ∘ decwVec - where - packW ∷ Int16 → Word8 - packW w - = let w' | w > 1024 = 1024 - | w < -1024 = -1024 - | otherwise = w - w'' | w' > 0 = w' - ((w' + 64) `shiftR` 7) - | otherwise = w' - w''' = (w'' + 4) `shiftR` 3 - in - fromIntegral w''' + put = UV.mapM_ (putWord8 ∘ packWeight) ∘ decwVec get = do n ← remaining - vec ← UV.replicateM (fromIntegral n) $ fmap unpackW getWord8 + vec ← UV.replicateM (fromIntegral n) + $ fmap unpackWeight getWord8 -- THINKME: the same caution as DecorrTerms, but never - -- try to reverse the vector simply. Think about the + -- try to simply reverse the vector. Think about the -- interleaving. return $ DecorrWeights vec - where - unpackW ∷ Word8 → Int16 - unpackW w - = let w' ∷ Int8 - w' = fromIntegral w - w'' ∷ Int16 - w'' = (fromIntegral w') `shiftL` 3 - w''' | w'' > 0 = w'' + ((w'' + 64) `shiftR` 7) - | otherwise = w'' - in - w''' + +-- | Decorrelation samples +data DecorrSamples + = DecorrSamples { + -- | The decorrelation sample vector stored in the metadata + -- as-is. Actual interpretation of the vector depends on the + -- number of channels and each corresponding decorrelation + -- terms. + decsVec ∷ !(UV.Vector Int32) + } + deriving (Eq, Show, Typeable) + +instance Metadata DecorrSamples where + metaID _ = 0x04 + metaSize = fromIntegral ∘ (⋅ 2) ∘ UV.length ∘ decsVec + +instance Binary DecorrSamples where + put = UV.mapM_ (putWord16le ∘ fromIntegral ∘ log2s) ∘ decsVec + get = do n ← remaining + vec ← UV.replicateM (fromIntegral $ n `div` 2) + $ fmap (exp2s ∘ fromIntegral) getWord16le + return $ DecorrSamples vec -- | RIFF header for .wav files (before audio) data RIFFHeader diff --git a/wavpack.cabal b/wavpack.cabal index cead654..7001778 100644 --- a/wavpack.cabal +++ b/wavpack.cabal @@ -38,6 +38,7 @@ Library Codec.Audio.WavPack Codec.Audio.WavPack.Block Codec.Audio.WavPack.Decorrelation + Codec.Audio.WavPack.Internal Codec.Audio.WavPack.Metadata GHC-Options: