AudioData: Add helper methods for interleaving/deinterleaving samples

modules/juce_audio_basics/buffers/juce_AudioDataConverters.cpp

@@ -434,32 +434,14 @@ void AudioDataConverters::convertFormatToFloat (DataFormat sourceFormat, const v
 //==============================================================================
 void AudioDataConverters::interleaveSamples (const float** source, float* dest, int numSamples, int numChannels)
 {
-    for (int chan = 0; chan < numChannels; ++chan)
+    AudioData::interleaveSamples<AudioData::Float32, AudioData::NativeEndian,
-    {
+                                 AudioData::Float32, AudioData::NativeEndian> (source, numChannels, dest, numChannels, numSamples);
-        auto i = chan;
-        auto src = source [chan];
-
-        for (int j = 0; j < numSamples; ++j)
-        {
-            dest [i] = src [j];
-            i += numChannels;
-        }
-    }
 }
 
 void AudioDataConverters::deinterleaveSamples (const float* source, float** dest, int numSamples, int numChannels)
 {
-    for (int chan = 0; chan < numChannels; ++chan)
+    AudioData::deinterleaveSamples<AudioData::Float32, AudioData::NativeEndian,
-    {
+                                   AudioData::Float32, AudioData::NativeEndian> (source, numChannels, dest, numChannels, numSamples);
-        auto i = chan;
-        auto dst = dest [chan];
-
-        for (int j = 0; j < numSamples; ++j)
-        {
-            dst [j] = source [i];
-            i += numChannels;
-        }
-    }
 }
 
 
@@ -591,6 +573,50 @@ public:
         Test1 <AudioData::Int32>::test (*this, r);
         beginTest ("Round-trip conversion: Float32");
         Test1 <AudioData::Float32>::test (*this, r);
+
+        beginTest ("Interleaving");
+        {
+            constexpr auto numChannels = 4;
+            constexpr auto numSamples = 512;
+
+            AudioBuffer<float> sourceBuffer { numChannels, numSamples },
+                               destBuffer   { 1, numChannels * numSamples };
+
+            for (int ch = 0; ch < numChannels; ++ch)
+                for (int i = 0; i < numSamples; ++i)
+                    sourceBuffer.setSample (ch, i, r.nextFloat());
+
+            AudioData::interleaveSamples<AudioData::Float32, AudioData::NativeEndian,
+                                         AudioData::Float32, AudioData::NativeEndian> (sourceBuffer.getArrayOfReadPointers(), numChannels,
+                                                                                       destBuffer.getWritePointer (0), numChannels,
+                                                                                       numSamples);
+
+            for (int ch = 0; ch < numChannels; ++ch)
+                for (int i = 0; i < numSamples; ++i)
+                    expect (destBuffer.getSample (0, ch + (i * numChannels)) == sourceBuffer.getSample (ch, i));
+        }
+
+        beginTest ("Deinterleaving");
+        {
+            constexpr auto numChannels = 4;
+            constexpr auto numSamples = 512;
+
+            AudioBuffer<float> sourceBuffer { 1, numChannels * numSamples },
+                               destBuffer   { numChannels, numSamples };
+
+            for (int ch = 0; ch < numChannels; ++ch)
+                for (int i = 0; i < numSamples; ++i)
+                    sourceBuffer.setSample (0, ch + (i * numChannels), r.nextFloat());
+
+            AudioData::deinterleaveSamples<AudioData::Float32, AudioData::NativeEndian,
+                                           AudioData::Float32, AudioData::NativeEndian> (sourceBuffer.getReadPointer (0), numChannels,
+                                                                                         destBuffer.getArrayOfWritePointers(), numChannels,
+                                                                                         numSamples);
+
+            for (int ch = 0; ch < numChannels; ++ch)
+                for (int i = 0; i < numSamples; ++i)
+                    expect (sourceBuffer.getSample (0, ch + (i * numChannels)) == destBuffer.getSample (ch, i));
+        }
     }
 };
 

modules/juce_audio_basics/buffers/juce_AudioDataConverters.h

@@ -639,10 +639,69 @@ public:
 
         const int sourceChannels, destChannels;
     };
+
+    //==============================================================================
+    template <typename T>
+    using SourceDataPointerType = const typename std::remove_pointer<decltype (T::data)>::type*;
+
+    /** A helper function for converting a sequence of samples from a non-interleaved source
+        to an interleaved destination.
+    */
+    template <typename SourceSampleFormat, typename SourceEndianness,
+              typename DestSampleFormat,   typename DestEndianness>
+    static void interleaveSamples (SourceDataPointerType<SourceSampleFormat>* sourceData, int numSourceChannels,
+                                   decltype (DestSampleFormat::data) destData, int numDestChannels,
+                                   int numSamples)
+    {
+        using SourceType = Pointer <SourceSampleFormat, SourceEndianness, NonInterleaved, Const>;
+        using DestType   = Pointer <DestSampleFormat,   DestEndianness,   Interleaved,    NonConst>;
+
+        for (int i = 0; i < numDestChannels; ++i)
+        {
+            const DestType dest (addBytesToPointer (destData, i * DestType::getBytesPerSample()), numDestChannels);
+
+            if (i < numSourceChannels)
+            {
+                if (*sourceData != nullptr)
+                {
+                    dest.convertSamples (SourceType (*sourceData), numSamples);
+                    ++sourceData;
+                }
+            }
+            else
+            {
+                dest.clearSamples (numSamples);
+            }
+        }
+    }
+
+    /** A helper function for converting a sequence of samples from an interleaved source
+        to a non-interleaved destination.
+    */
+    template <typename SourceSampleFormat, typename SourceEndianness,
+              typename DestSampleFormat,   typename DestEndianness>
+    static void deinterleaveSamples (SourceDataPointerType<SourceSampleFormat> sourceData, int numSourceChannels,
+                                     decltype (DestSampleFormat::data)* destData, int numDestChannels,
+                                     int numSamples)
+    {
+        using SourceType = Pointer <SourceSampleFormat, SourceEndianness, Interleaved,    Const>;
+        using DestType   = Pointer <DestSampleFormat,   DestEndianness,   NonInterleaved, NonConst>;
+
+        for (int i = 0; i < numDestChannels; ++i)
+        {
+            if (auto* targetChan = destData[i])
+            {
+                const DestType dest (targetChan);
+
+                if (i < numSourceChannels)
+                    dest.convertSamples (SourceType (addBytesToPointer (sourceData, i * SourceType::getBytesPerSample()), numSourceChannels), numSamples);
+                else
+                    dest.clearSamples (numSamples);
+            }
+        }
+    }
 };
 
-
-
 //==============================================================================
 #ifndef DOXYGEN