[AT3P] MDCT code

4 files changed, 261 insertions, 0 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index d40f6e6..ac02187 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -96,6 +96,7 @@ set(SOURCE_ATRACDENC_IMPL
     atrac/at3p/at3p.cpp
     atrac/at3p/at3p_bitstream.cpp
     atrac/at3p/at3p_gha.cpp
+    atrac/at3p/at3p_mdct.cpp
     atrac/at3p/at3p_tables.cpp
     lib/mdct/mdct.cpp
 )
diff --git a/src/atrac/at3p/at3p_mdct.cpp b/src/atrac/at3p/at3p_mdct.cpp
new file mode 100644
index 0000000..b92e87b
--- /dev/null
+++ b/src/atrac/at3p/at3p_mdct.cpp
@@ -0,0 +1,104 @@
+/*
+ * This file is part of AtracDEnc.
+ *
+ * AtracDEnc is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * AtracDEnc is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with AtracDEnc; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "at3p_mdct.h"
+#include "util.h"
+
+#include <array>
+
+#include <iostream>
+#include <vector>
+
+using std::vector;
+
+namespace NAtracDEnc {
+
+static std::array<float, 128> SineWin;
+
+static void InitSineWin() {
+    if (SineWin[SineWin.size() - 1] == 0.0) {
+        for (size_t i = 0; i < SineWin.size(); i++) {
+            SineWin[i] = 2.0 * sinf((i + 0.5) * (M_PI / (2.0 * SineWin.size())));
+        }
+    }
+}
+
+TAt3pMDCT::TAt3pMDCT()
+{
+    InitSineWin();
+}
+
+void TAt3pMDCT::Do(float specs[2048], const TPcmBandsData& bands, THistBuf& work)
+{
+    for (size_t b = 0; b < 16; b++) {
+        const float* srcBuff = bands[b];
+        float* const curSpec = &specs[b*128];
+
+        std::array<float, 256>& tmp = work[b];
+
+        for (size_t i = 0; i < 128; i++) {
+            tmp[128 + i] = SineWin[127 - i] * srcBuff[i];
+        }
+
+        const vector<float>& sp = Mdct(tmp.data());
+
+        memcpy(curSpec, sp.data(), 128 * sizeof(float));
+
+        if (b & 1) {
+            SwapArray(curSpec, 128);
+        }
+
+        for (size_t i = 0; i < 128; i++) {
+            tmp[i] = SineWin[i] * srcBuff[i];
+        }
+    }
+}
+
+TAt3pMIDCT::TAt3pMIDCT()
+{
+    InitSineWin();
+}
+
+void TAt3pMIDCT::Do(float specs[2048], TPcmBandsData& bands, THistBuf& work)
+{
+    for (size_t b = 0; b < 16; b++) {
+        float* dstBuff = bands[b];
+        float* const curSpec = &specs[b*128];
+
+        std::array<float, 128>& tmp = work[b];
+
+        if (b & 1) {
+            SwapArray(curSpec, 128);
+        }
+
+        vector<float> inv  = Midct(curSpec);
+
+        for (int j = 0; j < 128; ++j) {
+            inv[j] *= SineWin[j];
+            inv[255 - j] *= SineWin[j];
+        }
+
+        for (uint32_t j = 0; j < 128; ++j) {
+            dstBuff[j] = inv[j] + tmp[j];
+        }
+
+        memcpy(tmp.data(), &inv[128], sizeof(float)*128);
+    }
+}
+
+};
diff --git a/src/atrac/at3p/at3p_mdct.h b/src/atrac/at3p/at3p_mdct.h
new file mode 100644
index 0000000..de67245
--- /dev/null
+++ b/src/atrac/at3p/at3p_mdct.h
@@ -0,0 +1,50 @@
+/*
+ * This file is part of AtracDEnc.
+ *
+ * AtracDEnc is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * AtracDEnc is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with AtracDEnc; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#pragma once
+
+#include <array>
+#include <config.h>
+
+#include "lib/mdct/mdct.h"
+
+namespace NAtracDEnc {
+
+class TAt3pMDCT {
+public:
+    TAt3pMDCT();
+    using THistBuf = std::array<std::array<float, 256>, 16>;
+    using TPcmBandsData = std::array<const float*, 16>;
+
+    void Do(float specs[2048], const TPcmBandsData& bands, THistBuf& work);
+private:
+    NMDCT::TMDCT<256> Mdct;
+};
+
+class TAt3pMIDCT {
+public:
+    TAt3pMIDCT();
+    using THistBuf = std::array<std::array<float, 128>, 16>;
+    using TPcmBandsData = std::array<float*, 16>;
+
+    void Do(float specs[2048], TPcmBandsData& bands, THistBuf& work);
+private:
+    NMDCT::TMIDCT<256> Midct;
+};
+
+}
diff --git a/src/atrac/at3p/at3p_mdct_ut.cpp b/src/atrac/at3p/at3p_mdct_ut.cpp
new file mode 100644
index 0000000..c74eb47
--- /dev/null
+++ b/src/atrac/at3p/at3p_mdct_ut.cpp
@@ -0,0 +1,106 @@
+/*
+ * This file is part of AtracDEnc.
+ *
+ * AtracDEnc is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * AtracDEnc is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with AtracDEnc; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "at3p_mdct.h"
+#include <gtest/gtest.h>
+
+#include <vector>
+#include <cmath>
+
+using namespace NAtracDEnc;
+
+TEST(TAtpMDCT, ZeroOneBlock) {
+    std::array<float, 2048> specs;
+    static std::array<float, 2048> zero;
+
+    {
+        TAt3pMDCT mdct;
+
+        static TAt3pMDCT::THistBuf buff;
+
+        TAt3pMDCT::TPcmBandsData pcm;
+        for (size_t i = 0; i < pcm.size(); i++) {
+            pcm[i] = &zero[i * 128];
+        }
+
+        mdct.Do(specs.data(), pcm, buff);
+
+        for(auto s: specs)
+            EXPECT_NEAR(s, 0.0, 0.0000000001);
+    }
+
+    {
+        TAt3pMIDCT midct;
+
+        TAt3pMIDCT::TPcmBandsData pcm;
+        static TAt3pMIDCT::THistBuf buff;
+        for (size_t i = 0; i < pcm.size(); i++) {
+            pcm[i] = &zero[i * 128];
+        }
+
+        midct.Do(specs.data(), pcm, buff);
+
+        for(size_t i = 0; i < zero.size(); ++i)
+            EXPECT_NEAR(zero[i], 0.0, 0.0000000001);
+    }
+}
+
+
+TEST(TAtpMDCT, DC) {
+    std::array<float, 4096> specs;
+    std::array<float, 2048> dc;
+
+    for (size_t i = 0; i < dc.size(); i++) {
+        dc[i] = 1.0;
+    }
+
+    {
+        TAt3pMDCT mdct;
+
+        static TAt3pMDCT::THistBuf buff;
+
+        TAt3pMDCT::TPcmBandsData pcm;
+        for (size_t i = 0; i < pcm.size(); i++) {
+            pcm[i] = &dc[i * 128];
+        }
+
+        mdct.Do(specs.data(),        pcm, buff);
+        mdct.Do(specs.data() + 2048, pcm, buff);
+    }
+
+    {
+        TAt3pMIDCT midct;
+
+        std::array<float, 2048> result;
+
+        TAt3pMIDCT::TPcmBandsData pcm;
+
+        static TAt3pMIDCT::THistBuf buff;
+
+        for (size_t i = 0; i < pcm.size(); i++) {
+            pcm[i] = &result[i * 128];
+        }
+
+        midct.Do(specs.data(),        pcm, buff);
+        midct.Do(specs.data() + 2048, pcm, buff);
+
+        for(size_t i = 0; i < result.size(); ++i) {
+            EXPECT_NEAR(result[i], dc[i], 0.000001);
+        }
+    }
+}