Revert "Don't apply the HF scaling for "upsampling" ambisonics"

This reverts commit bf3f63fb4c5faa45784d7433d68b7013e29ee2c1.

alc/effects/convolution.cpp

@@ -194,6 +194,8 @@ struct ConvolutionState final : public EffectState {
 
     struct ChannelData {
         alignas(16) FloatBufferLine mBuffer{};
+        float mHfScale{};
+        BandSplitter mFilter{};
         float Current[MAX_OUTPUT_CHANNELS]{};
         float Target[MAX_OUTPUT_CHANNELS]{};
     };
@@ -233,6 +235,7 @@ void ConvolutionState::UpsampleMix(const al::span<FloatBufferLine> samplesOut,
     for(auto &chan : *mChans)
     {
         const al::span<float> src{chan.mBuffer.data(), samplesToDo};
+        chan.mFilter.processHfScale(src, chan.mHfScale);
         MixSamples(src, samplesOut, chan.Current, chan.Target, samplesToDo, 0);
     }
 }
@@ -277,6 +280,10 @@ void ConvolutionState::deviceUpdate(const DeviceBase *device, const Buffer &buff
         (uint64_t{buffer.storage->mSampleLen}*device->Frequency+(buffer.storage->mSampleRate-1)) /
         buffer.storage->mSampleRate);
 
+    const BandSplitter splitter{device->mXOverFreq / static_cast<float>(device->Frequency)};
+    for(auto &e : *mChans)
+        e.mFilter = splitter;
+
     mFilter.resize(numChannels, {});
     mOutput.resize(numChannels, {});
 
@@ -411,7 +418,13 @@ void ConvolutionState::update(const ContextBase *context, const EffectSlot *slot
     {
         DeviceBase *device{context->mDevice};
         if(device->mAmbiOrder > mAmbiOrder)
+        {
             mMix = &ConvolutionState::UpsampleMix;
+            const auto scales = AmbiScale::GetHFOrderScales(mAmbiOrder, true);
+            (*mChans)[0].mHfScale = scales[0];
+            for(size_t i{1};i < mChans->size();++i)
+                (*mChans)[i].mHfScale = scales[1];
+        }
         mOutTarget = target.Main->Buffer;
 
         auto&& scales = GetAmbiScales(mAmbiScaling);

alc/effects/reverb.cpp

@@ -453,6 +453,8 @@ struct ReverbState final : public EffectState {
 
 
     bool mUpmixOutput{false};
+    std::array<float,MaxAmbiOrder+1> mOrderScales{};
+    std::array<std::array<BandSplitter,NUM_LINES>,2> mAmbiSplitter;
 
 
     static void DoMixRow(const al::span<float> OutBuffer, const al::span<const float,4> Gains,
@@ -499,19 +501,30 @@ struct ReverbState final : public EffectState {
     {
         ASSUME(todo > 0);
 
-        /* TODO: If HF scaling isn't needed for upsampling, the A-to-B-Format
+        /* When upsampling, the B-Format conversion needs to be done separately
-         * matrix can be included with the panning gains like non-upsampled
+         * so the proper HF scaling can be applied to each B-Format channel.
-         * output.
+         * The panning gains then pan and upsample the B-Format channels.
          */
         const al::span<float> tmpspan{al::assume_aligned<16>(mTempLine.data()), todo};
         for(size_t c{0u};c < NUM_LINES;c++)
         {
             DoMixRow(tmpspan, EarlyA2B[c], mEarlySamples[0].data(), mEarlySamples[0].size());
+
+            /* Apply scaling to the B-Format's HF response to "upsample" it to
+             * higher-order output.
+             */
+            const float hfscale{(c==0) ? mOrderScales[0] : mOrderScales[1]};
+            mAmbiSplitter[0][c].processHfScale(tmpspan, hfscale);
+
             MixSamples(tmpspan, samplesOut, mEarly.CurrentGain[c], mEarly.PanGain[c], todo, 0);
         }
         for(size_t c{0u};c < NUM_LINES;c++)
         {
             DoMixRow(tmpspan, LateA2B[c], mLateSamples[0].data(), mLateSamples[0].size());
+
+            const float hfscale{(c==0) ? mOrderScales[0] : mOrderScales[1]};
+            mAmbiSplitter[1][c].processHfScale(tmpspan, hfscale);
+
             MixSamples(tmpspan, samplesOut, mLate.CurrentGain[c], mLate.PanGain[c], todo, 0);
         }
     }
@@ -670,7 +683,19 @@ void ReverbState::deviceUpdate(const DeviceBase *device, const Buffer&)
     mDoFading = true;
     mOffset = 0;
 
-    mUpmixOutput = (device->mAmbiOrder > 1);
+    if(device->mAmbiOrder > 1)
+    {
+        mUpmixOutput = true;
+        mOrderScales = AmbiScale::GetHFOrderScales(1, true);
+    }
+    else
+    {
+        mUpmixOutput = false;
+        mOrderScales.fill(1.0f);
+    }
+    mAmbiSplitter[0][0].init(device->mXOverFreq / frequency);
+    std::fill(mAmbiSplitter[0].begin()+1, mAmbiSplitter[0].end(), mAmbiSplitter[0][0]);
+    std::fill(mAmbiSplitter[1].begin(), mAmbiSplitter[1].end(), mAmbiSplitter[0][0]);
 }
 
 /**************************************

core/ambidefs.cpp

@@ -366,3 +366,22 @@ const std::array<AmbiChannelFloatArray,9> AmbiScale::SecondOrder2DUp{CalcSecondO
 const std::array<AmbiChannelFloatArray,16> AmbiScale::ThirdOrderUp{CalcThirdOrderUp()};
 const std::array<AmbiChannelFloatArray,16> AmbiScale::ThirdOrder2DUp{CalcThirdOrder2DUp()};
 const std::array<AmbiChannelFloatArray,25> AmbiScale::FourthOrder2DUp{CalcFourthOrder2DUp()};
+
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale1O{{
+    2.000000000e+00f, 1.154700538e+00f
+}};
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale1O2D{{
+    1.414213562e+00f, 1.000000000e+00f
+}};
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale2O{{
+    1.972026594e+00f, 1.527525232e+00f, 7.888106377e-01f
+}};
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale2O2D{{
+    1.414213562e+00f, 1.224744871e+00f, 7.071067812e-01f
+}};
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale3O{{
+    1.865086714e+00f, 1.606093894e+00f, 1.142055301e+00f, 5.683795528e-01f
+}};
+const std::array<float,MaxAmbiOrder+1> AmbiScale::DecoderHFScale3O2D{{
+    1.414213562e+00f, 1.306562965e+00f, 1.000000000e+00f, 5.411961001e-01f
+}};

core/ambidefs.h

@@ -113,6 +113,20 @@ struct AmbiScale {
         return ret;
     }
 
+    /* Retrieves per-order HF scaling factors for "upsampling" ambisonic data. */
+    static std::array<float,MaxAmbiOrder+1> GetHFOrderScales(const uint order, const bool is3D) noexcept
+    {
+        if(order >= 3) return is3D ? DecoderHFScale3O : DecoderHFScale3O2D;
+        if(order == 2) return is3D ? DecoderHFScale2O : DecoderHFScale2O2D;
+        return is3D ? DecoderHFScale1O : DecoderHFScale1O2D;
+    }
+
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale1O;
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale1O2D;
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale2O;
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale2O2D;
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale3O;
+    static const std::array<float,MaxAmbiOrder+1> DecoderHFScale3O2D;
 
     static const std::array<std::array<float,MaxAmbiChannels>,4> FirstOrderUp;
     static const std::array<std::array<float,MaxAmbiChannels>,4> FirstOrder2DUp;

core/voice.cpp

@@ -892,20 +892,52 @@ void Voice::prepare(DeviceBase *device)
     /* Make sure the sample history is cleared. */
     std::fill(mPrevSamples.begin(), mPrevSamples.end(), HistoryLine{});
 
-    /* 2-channel UHJ needs different shelf filters. However, we can't just use
+    /* Don't need to set the VoiceIsAmbisonic flag if the device is not higher
-     * different shelf filters after mixing it, given any old speaker setup the
+     * order than the voice. No HF scaling is necessary to mix it.
-     * user has. To make this work, we apply the expected shelf filters for
-     * decoding UHJ2 to quad (only needs LF scaling), and act as if those 4
-     * quad channels are encoded right back into B-Format.
-     *
-     * This isn't perfect, but without an entirely separate and limited UHJ2
-     * path, it's better than nothing.
-     *
-     * Do not apply the shelf filter with UHJ output. UHJ2->B-Format->UHJ2 is
-     * identity, so don't mess with it.
      */
-    if(mFmtChannels == FmtUHJ2 && !device->mUhjEncoder)
+    if(mAmbiOrder && device->mAmbiOrder > mAmbiOrder)
     {
+        const uint8_t *OrderFromChan{Is2DAmbisonic(mFmtChannels) ?
+            AmbiIndex::OrderFrom2DChannel().data() : AmbiIndex::OrderFromChannel().data()};
+        const auto scales = AmbiScale::GetHFOrderScales(mAmbiOrder, !Is2DAmbisonic(mFmtChannels));
+
+        const BandSplitter splitter{device->mXOverFreq / static_cast<float>(device->Frequency)};
+        for(auto &chandata : mChans)
+        {
+            chandata.mAmbiHFScale = scales[*(OrderFromChan++)];
+            chandata.mAmbiLFScale = 1.0f;
+            chandata.mAmbiSplitter = splitter;
+            chandata.mDryParams = DirectParams{};
+            chandata.mDryParams.NFCtrlFilter = device->mNFCtrlFilter;
+            std::fill_n(chandata.mWetParams.begin(), device->NumAuxSends, SendParams{});
+        }
+        /* 2-channel UHJ needs different shelf filters. However, we can't just
+         * use different shelf filters after mixing it and with any old speaker
+         * setup the user has. To make this work, we apply the expected shelf
+         * filters for decoding UHJ2 to quad (only needs LF scaling), and act
+         * as if those 4 quad channels are encoded right back onto higher-order
+         * B-Format.
+         *
+         * This isn't perfect, but without an entirely separate and limited
+         * UHJ2 path, it's better than nothing.
+         */
+        if(mFmtChannels == FmtUHJ2)
+        {
+            mChans[0].mAmbiHFScale = 1.0f;
+            mChans[0].mAmbiLFScale = UhjDecoder<UhjLengthStd>::sWLFScale;
+            mChans[1].mAmbiHFScale = 1.0f;
+            mChans[1].mAmbiLFScale = UhjDecoder<UhjLengthStd>::sXYLFScale;
+            mChans[2].mAmbiHFScale = 1.0f;
+            mChans[2].mAmbiLFScale = UhjDecoder<UhjLengthStd>::sXYLFScale;
+        }
+        mFlags.set(VoiceIsAmbisonic);
+    }
+    else if(mFmtChannels == FmtUHJ2 && !device->mUhjEncoder)
+    {
+        /* 2-channel UHJ with first-order output also needs the shelf filter
+         * correction applied, except with UHJ output (UHJ2->B-Format->UHJ2 is
+         * identity, so don't mess with it).
+         */
         const BandSplitter splitter{device->mXOverFreq / static_cast<float>(device->Frequency)};
         for(auto &chandata : mChans)
         {