Clean qmf code. (#51)

- Remove unused TQmf template pcm type parameter
- Do not copy buffer twice in the synthesis fb

Author: dcherednik

src/atrac/atrac1_qmf.h

@@ -22,41 +22,40 @@
 
 namespace NAtracDEnc {
 
-template<class TIn>
 class Atrac1AnalysisFilterBank {
     const static int nInSamples = 512;
     const static int delayComp = 39;
-    TQmf<TIn, nInSamples> Qmf1;
-    TQmf<TIn, nInSamples / 2> Qmf2;
+    TQmf<nInSamples> Qmf1;
+    TQmf<nInSamples / 2> Qmf2;
     std::vector<float> MidLowTmp;
     std::vector<float> DelayBuf;
 public:
-    Atrac1AnalysisFilterBank() {
+    Atrac1AnalysisFilterBank() noexcept {
         MidLowTmp.resize(512);
         DelayBuf.resize(delayComp + 512);
     }
-    void Analysis(TIn* pcm, float* low, float* mid, float* hi) {
+    void Analysis(const float* pcm, float* low, float* mid, float* hi) noexcept {
         memcpy(&DelayBuf[0], &DelayBuf[256], sizeof(float) *  delayComp);
         Qmf1.Analysis(pcm, &MidLowTmp[0], &DelayBuf[delayComp]);
         Qmf2.Analysis(&MidLowTmp[0], low, mid);
         memcpy(hi, &DelayBuf[0], sizeof(float) * 256);
 
     }
 };
-template<class TOut>
+
 class Atrac1SynthesisFilterBank {
     const static int nInSamples = 512;
     const static int delayComp = 39;
-    TQmf<TOut, nInSamples> Qmf1;
-    TQmf<TOut, nInSamples / 2> Qmf2;
+    TQmf<nInSamples> Qmf1;
+    TQmf<nInSamples / 2> Qmf2;
     std::vector<float> MidLowTmp;
     std::vector<float> DelayBuf;
 public:
-    Atrac1SynthesisFilterBank() {
+    Atrac1SynthesisFilterBank() noexcept {
         MidLowTmp.resize(512);
         DelayBuf.resize(delayComp + 512);
     }
-    void Synthesis(TOut* pcm, float* low, float* mid, float* hi) {
+    void Synthesis(float* pcm, const float* low, const float* mid, const float* hi) noexcept {
         memcpy(&DelayBuf[0], &DelayBuf[256], sizeof(float) *  delayComp);
         memcpy(&DelayBuf[delayComp], hi, sizeof(float) * 256);
         Qmf2.Synthesis(&MidLowTmp[0], &low[0], &mid[0]);

src/atrac/atrac3_qmf.h

@@ -22,20 +22,19 @@
 
 namespace NAtracDEnc {
 
-template<class TIn>
 class Atrac3AnalysisFilterBank {
     const static int nInSamples = 1024;
-    TQmf<TIn, nInSamples> Qmf1;
-    TQmf<TIn, nInSamples / 2> Qmf2;
-    TQmf<TIn, nInSamples / 2> Qmf3;
+    TQmf<nInSamples> Qmf1;
+    TQmf<nInSamples / 2> Qmf2;
+    TQmf<nInSamples / 2> Qmf3;
     std::vector<float> Buf1;
     std::vector<float> Buf2;
 public:
-    Atrac3AnalysisFilterBank() {
+    Atrac3AnalysisFilterBank() noexcept {
         Buf1.resize(nInSamples);
         Buf2.resize(nInSamples);
     }
-    void Analysis(TIn* pcm, float* subs[4]) {
+    void Analysis(const float* pcm, float* subs[4]) noexcept {
         Qmf1.Analysis(pcm, Buf1.data(), Buf2.data());
         Qmf2.Analysis(Buf1.data(), subs[0], subs[1]);
         Qmf3.Analysis(Buf2.data(), subs[3], subs[2]);

src/atrac1denc.h

@@ -63,7 +63,7 @@ class TAtrac1Encoder : public IProcessor, public TAtrac1MDCT {
     std::array<std::array<float, 256 + 16>, 2> PcmBufMid;
     std::array<std::array<float, 512 + 16>, 2> PcmBufHi;
 
-    Atrac1AnalysisFilterBank<float> AnalysisFilterBank[2];
+    Atrac1AnalysisFilterBank AnalysisFilterBank[2];
 
     const std::vector<float> LoudnessCurve;
     std::vector<std::unique_ptr<NAtrac1::IAtrac1BitAlloc>> BitAllocs;
@@ -117,7 +117,7 @@ class TAtrac1Decoder : public IProcessor, public TAtrac1MDCT {
     int32_t PcmValueMax = 1;
     int32_t PcmValueMin = -1;
 
-    Atrac1SynthesisFilterBank<float> SynthesisFilterBank[2];
+    Atrac1SynthesisFilterBank SynthesisFilterBank[2];
 public:
     TAtrac1Decoder(TCompressedInputPtr&& aea);
     TPCMEngine::TProcessLambda GetLambda() override;

src/atrac3denc.h

@@ -89,7 +89,7 @@ class TAtrac3Encoder : public IProcessor, public TAtrac3MDCT {
 
     float PrevPeak[2][4] = {{0.0}}; //2 channel, 4 band - peak level (after windowing), used to check overflow during scalling
 
-    Atrac3AnalysisFilterBank<float> AnalysisFilterBank[2];
+    Atrac3AnalysisFilterBank AnalysisFilterBank[2];
 
     TScaler<TAtrac3Data> Scaler;
     std::vector<NAtrac3::TAtrac3BitStreamWriter::TSingleChannelElement> SingleChannelElements;

src/qmf/qmf.h

@@ -21,15 +21,14 @@
 
 #include "../config.h"
 
-template<class TPCM, int nIn>
+template<size_t nIn>
 class TQmf {
     static const float TapHalf[24];
     float QmfWindow[48];
-    TPCM PcmBuffer[nIn + 46];
+    float PcmBuffer[nIn + 46];
     float PcmBufferMerge[nIn + 46];
-    float DelayBuff[46];
 public:
-    TQmf() {
+    TQmf() noexcept {
         const int sz = sizeof(QmfWindow)/sizeof(QmfWindow[0]);
 
         for (size_t i = 0 ; i < sz/2; i++) {
@@ -41,13 +40,12 @@ class TQmf {
         }
     }
 
-    void Analysis(TPCM* in, float* lower, float* upper) {
+    void Analysis(const float* in, float* lower, float* upper) noexcept {
         float temp;
-        for (size_t i = 0; i < 46; i++)
-            PcmBuffer[i] = PcmBuffer[nIn + i];
 
-        for (size_t i = 0; i < nIn; i++)
-            PcmBuffer[46+i] = in[i];
+        memcpy(&PcmBuffer[0], &PcmBuffer[nIn], 46 * sizeof(float));
+
+        memcpy(&PcmBuffer[46], in, nIn * sizeof(float));
 
         for (size_t j = 0; j < nIn; j+=2) {
             lower[j/2] = upper[j/2] = 0.0;
@@ -61,10 +59,9 @@ class TQmf {
         }
     }
 
-    void Synthesis(TPCM* out, float* lower, float* upper) {
-        memcpy(&PcmBufferMerge[0], &DelayBuff[0], 46*sizeof(float));
+    void Synthesis(float* out, const float* lower, const float* upper) noexcept {
         float* newPart = &PcmBufferMerge[46];
-        for (int i = 0; i < nIn; i+=4) {
+        for (size_t i = 0; i < nIn; i+=4) {
             newPart[i+0] = lower[i/2] + upper[i/2];
             newPart[i+1] = lower[i/2] - upper[i/2];
             newPart[i+2] = lower[i/2 + 1] + upper[i/2 + 1];
@@ -84,12 +81,12 @@ class TQmf {
             winP += 2;
             out += 2;
         }
-        memcpy(&DelayBuff[0], &PcmBufferMerge[nIn], 46*sizeof(float));
+        memcpy(&PcmBufferMerge[0], &PcmBufferMerge[nIn], 46 * sizeof(float));
     }
 };
 
-template<class TPCM, int nIn>
-const float TQmf<TPCM, nIn>::TapHalf[24] = {
+template<size_t nIn>
+const float TQmf<nIn>::TapHalf[24] = {
     -0.00001461907,  -0.00009205479, -0.000056157569,  0.00030117269,
     0.0002422519,    -0.00085293897, -0.0005205574,    0.0020340169,
     0.00078333891,   -0.0042153862,  -0.00075614988,   0.0078402944,