1 files changed, 371 insertions, 0 deletions
diff --git a/core/converter.cpp b/core/converter.cpp
new file mode 100644
index 00000000..6a06b464
--- /dev/null
+++ b/core/converter.cpp
@@ -0,0 +1,371 @@
+
+#include "config.h"
+
+#include "converter.h"
+
+#include <algorithm>
+#include <cmath>
+#include <cstdint>
+#include <iterator>
+#include <limits.h>
+
+#include "albit.h"
+#include "albyte.h"
+#include "alnumeric.h"
+#include "fpu_ctrl.h"
+
+struct CTag;
+struct CopyTag;
+
+
+namespace {
+
+constexpr uint MaxPitch{10};
+
+static_assert((BufferLineSize-1)/MaxPitch > 0, "MaxPitch is too large for BufferLineSize!");
+static_assert((INT_MAX>>MixerFracBits)/MaxPitch > BufferLineSize,
+    "MaxPitch and/or BufferLineSize are too large for MixerFracBits!");
+
+/* Base template left undefined. Should be marked =delete, but Clang 3.8.1
+ * chokes on that given the inline specializations.
+ */
+template<DevFmtType T>
+inline float LoadSample(DevFmtType_t<T> val) noexcept;
+
+template<> inline float LoadSample<DevFmtByte>(DevFmtType_t<DevFmtByte> val) noexcept
+{ return val * (1.0f/128.0f); }
+template<> inline float LoadSample<DevFmtShort>(DevFmtType_t<DevFmtShort> val) noexcept
+{ return val * (1.0f/32768.0f); }
+template<> inline float LoadSample<DevFmtInt>(DevFmtType_t<DevFmtInt> val) noexcept
+{ return static_cast<float>(val) * (1.0f/2147483648.0f); }
+template<> inline float LoadSample<DevFmtFloat>(DevFmtType_t<DevFmtFloat> val) noexcept
+{ return val; }
+
+template<> inline float LoadSample<DevFmtUByte>(DevFmtType_t<DevFmtUByte> val) noexcept
+{ return LoadSample<DevFmtByte>(static_cast<int8_t>(val - 128)); }
+template<> inline float LoadSample<DevFmtUShort>(DevFmtType_t<DevFmtUShort> val) noexcept
+{ return LoadSample<DevFmtShort>(static_cast<int16_t>(val - 32768)); }
+template<> inline float LoadSample<DevFmtUInt>(DevFmtType_t<DevFmtUInt> val) noexcept
+{ return LoadSample<DevFmtInt>(static_cast<int32_t>(val - 2147483648u)); }
+
+
+template<DevFmtType T>
+inline void LoadSampleArray(float *RESTRICT dst, const void *src, const size_t srcstep,
+    const size_t samples) noexcept
+{
+    const DevFmtType_t<T> *ssrc = static_cast<const DevFmtType_t<T>*>(src);
+    for(size_t i{0u};i < samples;i++)
+        dst[i] = LoadSample<T>(ssrc[i*srcstep]);
+}
+
+void LoadSamples(float *dst, const void *src, const size_t srcstep, const DevFmtType srctype,
+    const size_t samples) noexcept
+{
+#define HANDLE_FMT(T)                                                         \
+    case T: LoadSampleArray<T>(dst, src, srcstep, samples); break
+    switch(srctype)
+    {
+        HANDLE_FMT(DevFmtByte);
+        HANDLE_FMT(DevFmtUByte);
+        HANDLE_FMT(DevFmtShort);
+        HANDLE_FMT(DevFmtUShort);
+        HANDLE_FMT(DevFmtInt);
+        HANDLE_FMT(DevFmtUInt);
+        HANDLE_FMT(DevFmtFloat);
+    }
+#undef HANDLE_FMT
+}
+
+
+template<DevFmtType T>
+inline DevFmtType_t<T> StoreSample(float) noexcept;
+
+template<> inline float StoreSample<DevFmtFloat>(float val) noexcept
+{ return val; }
+template<> inline int32_t StoreSample<DevFmtInt>(float val) noexcept
+{ return fastf2i(clampf(val*2147483648.0f, -2147483648.0f, 2147483520.0f)); }
+template<> inline int16_t StoreSample<DevFmtShort>(float val) noexcept
+{ return static_cast<int16_t>(fastf2i(clampf(val*32768.0f, -32768.0f, 32767.0f))); }
+template<> inline int8_t StoreSample<DevFmtByte>(float val) noexcept
+{ return static_cast<int8_t>(fastf2i(clampf(val*128.0f, -128.0f, 127.0f))); }
+
+/* Define unsigned output variations. */
+template<> inline uint32_t StoreSample<DevFmtUInt>(float val) noexcept
+{ return static_cast<uint32_t>(StoreSample<DevFmtInt>(val)) + 2147483648u; }
+template<> inline uint16_t StoreSample<DevFmtUShort>(float val) noexcept
+{ return static_cast<uint16_t>(StoreSample<DevFmtShort>(val) + 32768); }
+template<> inline uint8_t StoreSample<DevFmtUByte>(float val) noexcept
+{ return static_cast<uint8_t>(StoreSample<DevFmtByte>(val) + 128); }
+
+template<DevFmtType T>
+inline void StoreSampleArray(void *dst, const float *RESTRICT src, const size_t dststep,
+    const size_t samples) noexcept
+{
+    DevFmtType_t<T> *sdst = static_cast<DevFmtType_t<T>*>(dst);
+    for(size_t i{0u};i < samples;i++)
+        sdst[i*dststep] = StoreSample<T>(src[i]);
+}
+
+
+void StoreSamples(void *dst, const float *src, const size_t dststep, const DevFmtType dsttype,
+    const size_t samples) noexcept
+{
+#define HANDLE_FMT(T)                                                         \
+    case T: StoreSampleArray<T>(dst, src, dststep, samples); break
+    switch(dsttype)
+    {
+        HANDLE_FMT(DevFmtByte);
+        HANDLE_FMT(DevFmtUByte);
+        HANDLE_FMT(DevFmtShort);
+        HANDLE_FMT(DevFmtUShort);
+        HANDLE_FMT(DevFmtInt);
+        HANDLE_FMT(DevFmtUInt);
+        HANDLE_FMT(DevFmtFloat);
+    }
+#undef HANDLE_FMT
+}
+
+
+template<DevFmtType T>
+void Mono2Stereo(float *RESTRICT dst, const void *src, const size_t frames) noexcept
+{
+    const DevFmtType_t<T> *ssrc = static_cast<const DevFmtType_t<T>*>(src);
+    for(size_t i{0u};i < frames;i++)
+        dst[i*2 + 1] = dst[i*2 + 0] = LoadSample<T>(ssrc[i]) * 0.707106781187f;
+}
+
+template<DevFmtType T>
+void Multi2Mono(uint chanmask, const size_t step, const float scale, float *RESTRICT dst,
+    const void *src, const size_t frames) noexcept
+{
+    const DevFmtType_t<T> *ssrc = static_cast<const DevFmtType_t<T>*>(src);
+    std::fill_n(dst, frames, 0.0f);
+    for(size_t c{0};chanmask;++c)
+    {
+        if LIKELY((chanmask&1))
+        {
+            for(size_t i{0u};i < frames;i++)
+                dst[i] += LoadSample<T>(ssrc[i*step + c]);
+        }
+        chanmask >>= 1;
+    }
+    for(size_t i{0u};i < frames;i++)
+        dst[i] *= scale;
+}
+
+} // namespace
+
+SampleConverterPtr CreateSampleConverter(DevFmtType srcType, DevFmtType dstType, size_t numchans,
+    uint srcRate, uint dstRate, Resampler resampler)
+{
+    if(numchans < 1 || srcRate < 1 || dstRate < 1)
+        return nullptr;
+
+    SampleConverterPtr converter{new(FamCount(numchans)) SampleConverter{numchans}};
+    converter->mSrcType = srcType;
+    converter->mDstType = dstType;
+    converter->mSrcTypeSize = BytesFromDevFmt(srcType);
+    converter->mDstTypeSize = BytesFromDevFmt(dstType);
+
+    converter->mSrcPrepCount = 0;
+    converter->mFracOffset = 0;
+
+    /* Have to set the mixer FPU mode since that's what the resampler code expects. */
+    FPUCtl mixer_mode{};
+    auto step = static_cast<uint>(
+        mind(srcRate*double{MixerFracOne}/dstRate + 0.5, MaxPitch*MixerFracOne));
+    converter->mIncrement = maxu(step, 1);
+    if(converter->mIncrement == MixerFracOne)
+        converter->mResample = Resample_<CopyTag,CTag>;
+    else
+        converter->mResample = PrepareResampler(resampler, converter->mIncrement,
+            &converter->mState);
+
+    return converter;
+}
+
+uint SampleConverter::availableOut(uint srcframes) const
+{
+    int prepcount{mSrcPrepCount};
+    if(prepcount < 0)
+    {
+        /* Negative prepcount means we need to skip that many input samples. */
+        if(static_cast<uint>(-prepcount) >= srcframes)
+            return 0;
+        srcframes -= static_cast<uint>(-prepcount);
+        prepcount = 0;
+    }
+
+    if(srcframes < 1)
+    {
+        /* No output samples if there's no input samples. */
+        return 0;
+    }
+
+    if(prepcount < MaxResamplerPadding
+        && static_cast<uint>(MaxResamplerPadding - prepcount) >= srcframes)
+    {
+        /* Not enough input samples to generate an output sample. */
+        return 0;
+    }
+
+    auto DataSize64 = static_cast<uint64_t>(prepcount);
+    DataSize64 += srcframes;
+    DataSize64 -= MaxResamplerPadding;
+    DataSize64 <<= MixerFracBits;
+    DataSize64 -= mFracOffset;
+
+    /* If we have a full prep, we can generate at least one sample. */
+    return static_cast<uint>(clampu64((DataSize64 + mIncrement-1)/mIncrement, 1,
+        std::numeric_limits<int>::max()));
+}
+
+uint SampleConverter::convert(const void **src, uint *srcframes, void *dst, uint dstframes)
+{
+    const uint SrcFrameSize{static_cast<uint>(mChan.size()) * mSrcTypeSize};
+    const uint DstFrameSize{static_cast<uint>(mChan.size()) * mDstTypeSize};
+    const uint increment{mIncrement};
+    auto SamplesIn = static_cast<const al::byte*>(*src);
+    uint NumSrcSamples{*srcframes};
+
+    FPUCtl mixer_mode{};
+    uint pos{0};
+    while(pos < dstframes && NumSrcSamples > 0)
+    {
+        int prepcount{mSrcPrepCount};
+        if(prepcount < 0)
+        {
+            /* Negative prepcount means we need to skip that many input samples. */
+            if(static_cast<uint>(-prepcount) >= NumSrcSamples)
+            {
+                mSrcPrepCount = static_cast<int>(NumSrcSamples) + prepcount;
+                NumSrcSamples = 0;
+                break;
+            }
+            SamplesIn += SrcFrameSize*static_cast<uint>(-prepcount);
+            NumSrcSamples -= static_cast<uint>(-prepcount);
+            mSrcPrepCount = 0;
+            continue;
+        }
+        const uint toread{minu(NumSrcSamples, BufferLineSize - MaxResamplerPadding)};
+
+        if(prepcount < MaxResamplerPadding
+            && static_cast<uint>(MaxResamplerPadding - prepcount) >= toread)
+        {
+            /* Not enough input samples to generate an output sample. Store
+             * what we're given for later.
+             */
+            for(size_t chan{0u};chan < mChan.size();chan++)
+                LoadSamples(&mChan[chan].PrevSamples[prepcount], SamplesIn + mSrcTypeSize*chan,
+                    mChan.size(), mSrcType, toread);
+
+            mSrcPrepCount = prepcount + static_cast<int>(toread);
+            NumSrcSamples = 0;
+            break;
+        }
+
+        float *RESTRICT SrcData{mSrcSamples};
+        float *RESTRICT DstData{mDstSamples};
+        uint DataPosFrac{mFracOffset};
+        auto DataSize64 = static_cast<uint64_t>(prepcount);
+        DataSize64 += toread;
+        DataSize64 -= MaxResamplerPadding;
+        DataSize64 <<= MixerFracBits;
+        DataSize64 -= DataPosFrac;
+
+        /* If we have a full prep, we can generate at least one sample. */
+        auto DstSize = static_cast<uint>(
+            clampu64((DataSize64 + increment-1)/increment, 1, BufferLineSize));
+        DstSize = minu(DstSize, dstframes-pos);
+
+        for(size_t chan{0u};chan < mChan.size();chan++)
+        {
+            const al::byte *SrcSamples{SamplesIn + mSrcTypeSize*chan};
+            al::byte *DstSamples = static_cast<al::byte*>(dst) + mDstTypeSize*chan;
+
+            /* Load the previous samples into the source data first, then the
+             * new samples from the input buffer.
+             */
+            std::copy_n(mChan[chan].PrevSamples, prepcount, SrcData);
+            LoadSamples(SrcData + prepcount, SrcSamples, mChan.size(), mSrcType, toread);
+
+            /* Store as many prep samples for next time as possible, given the
+             * number of output samples being generated.
+             */
+            uint SrcDataEnd{(DstSize*increment + DataPosFrac)>>MixerFracBits};
+            if(SrcDataEnd >= static_cast<uint>(prepcount)+toread)
+                std::fill(std::begin(mChan[chan].PrevSamples),
+                    std::end(mChan[chan].PrevSamples), 0.0f);
+            else
+            {
+                const size_t len{minz(al::size(mChan[chan].PrevSamples),
+                    static_cast<uint>(prepcount)+toread-SrcDataEnd)};
+                std::copy_n(SrcData+SrcDataEnd, len, mChan[chan].PrevSamples);
+                std::fill(std::begin(mChan[chan].PrevSamples)+len,
+                    std::end(mChan[chan].PrevSamples), 0.0f);
+            }
+
+            /* Now resample, and store the result in the output buffer. */
+            const float *ResampledData{mResample(&mState, SrcData+(MaxResamplerPadding>>1),
+                DataPosFrac, increment, {DstData, DstSize})};
+
+            StoreSamples(DstSamples, ResampledData, mChan.size(), mDstType, DstSize);
+        }
+
+        /* Update the number of prep samples still available, as well as the
+         * fractional offset.
+         */
+        DataPosFrac += increment*DstSize;
+        mSrcPrepCount = mini(prepcount + static_cast<int>(toread - (DataPosFrac>>MixerFracBits)),
+            MaxResamplerPadding);
+        mFracOffset = DataPosFrac & MixerFracMask;
+
+        /* Update the src and dst pointers in case there's still more to do. */
+        SamplesIn += SrcFrameSize*(DataPosFrac>>MixerFracBits);
+        NumSrcSamples -= minu(NumSrcSamples, (DataPosFrac>>MixerFracBits));
+
+        dst = static_cast<al::byte*>(dst) + DstFrameSize*DstSize;
+        pos += DstSize;
+    }
+
+    *src = SamplesIn;
+    *srcframes = NumSrcSamples;
+
+    return pos;
+}
+
+
+void ChannelConverter::convert(const void *src, float *dst, uint frames) const
+{
+    if(mDstChans == DevFmtMono)
+    {
+        const float scale{std::sqrt(1.0f / static_cast<float>(al::popcount(mChanMask)))};
+        switch(mSrcType)
+        {
+#define HANDLE_FMT(T) case T: Multi2Mono<T>(mChanMask, mSrcStep, scale, dst, src, frames); break
+        HANDLE_FMT(DevFmtByte);
+        HANDLE_FMT(DevFmtUByte);
+        HANDLE_FMT(DevFmtShort);
+        HANDLE_FMT(DevFmtUShort);
+        HANDLE_FMT(DevFmtInt);
+        HANDLE_FMT(DevFmtUInt);
+        HANDLE_FMT(DevFmtFloat);
+#undef HANDLE_FMT
+        }
+    }
+    else if(mChanMask == 0x1 && mDstChans == DevFmtStereo)
+    {
+        switch(mSrcType)
+        {
+#define HANDLE_FMT(T) case T: Mono2Stereo<T>(dst, src, frames); break
+        HANDLE_FMT(DevFmtByte);
+        HANDLE_FMT(DevFmtUByte);
+        HANDLE_FMT(DevFmtShort);
+        HANDLE_FMT(DevFmtUShort);
+        HANDLE_FMT(DevFmtInt);
+        HANDLE_FMT(DevFmtUInt);
+        HANDLE_FMT(DevFmtFloat);
+#undef HANDLE_FMT
+        }
+    }
+}