UI: Audio visualizer uses the audio sub-document information and not some magic big functions

src/UI/AudioVisualizer.cc

@@ -10,9 +10,77 @@
 
 using namespace Vivy;
 
-AudioVisualizer::AudioVisualizer(QWidget *parent) noexcept
+#define MAXPIXVALUE 7 // Some magix AV magic stuff
+
+#define CAP_VALUE(_value, _lower, _upper)                                                          \
+    {                                                                                              \
+        if (_value > _upper) {                                                                     \
+            _value = _upper;                                                                       \
+        } else if (_value < _lower) {                                                              \
+            _value = _lower;                                                                       \
+        }                                                                                          \
+    }
+
+AudioVisualizer::AudioVisualizer(AudioContext::StreamPtr stream, QWidget *parent)
     : QWidget(parent)
 {
+    if (!stream->isDecoded()) {
+        qDebug() << "Need to decode data for stream" << stream->getStreamIndex();
+        stream->decodeData();
+    }
+
+    double *data = stream->getDecodedData();
+    if (data == nullptr)
+        throw std::logic_error("the passed stream is not decoded");
+
+    const size_t size     = stream->getDecodedDataSize();
+    const size_t height   = stream->getDecodedChunkSize();
+    const size_t decalage = stream->getDecodedDecalage();
+    const size_t width    = (size - height) / decalage;
+    uchar *pixels         = new uchar[static_cast<size_t>(width * height / 2)]();
+
+    FFTSamplePtr chunkData(
+        reinterpret_cast<FFTSample *>(av_malloc_array(2 * height, sizeof(FFTSample))),
+        fftSampleDeleter);
+    RDFTContextPtr ctx(av_rdft_init((static_cast<int>(log2(static_cast<int>(height)))), DFT_R2C),
+                       rdftContextDeleter);
+
+    if (!pixels) {
+        throw std::runtime_error("out of memory");
+    } else if (!(chunkData && ctx)) {
+        delete[] pixels;
+        throw std::runtime_error("out of memory");
+    }
+
+    /* Compute the image data */
+
+    for (size_t x = 0, i = 0; i < size - height; i += decalage, ++x) {
+#pragma omp parallel for
+        for (size_t j = 0; j < height; j++) {
+            const double curr_dat = data[i + j];
+            const double window_modifier =
+                (1 - cos(2 * M_PI * static_cast<double>(j) / static_cast<double>(height - 1))) / 2;
+            float value = static_cast<float>(window_modifier * curr_dat);
+            CAP_VALUE(value, -1.0f, 1.0f);
+            chunkData[j] = value;
+        }
+
+        av_rdft_calc(ctx.get(), chunkData.get());
+
+#pragma omp parallel for
+        for (size_t j = 0; j < height / 2; j++) {
+            const float im     = chunkData[j * 2];
+            const float re     = chunkData[j * 2 + 1];
+            const float mag    = sqrtf(im * im + re * re);
+            const size_t index = static_cast<size_t>(j * static_cast<ulong>(width) + x);
+            pixels[index]      = (unsigned char)(mag)*MAXPIXVALUE;
+        }
+    }
+
+    QImage img = QImage(pixels, static_cast<int>(width), static_cast<int>(height / 2),
+                        static_cast<int>(width), QImage::Format_Grayscale8, pixelsDeleter, pixels)
+                     .mirrored(false, true);
+    printSpectrum(img);
 }
 
 void
@@ -24,20 +92,3 @@ AudioVisualizer::printSpectrum(QImage pixmap) noexcept
     layout->addWidget(timer);
     setLayout(layout);
 }
-
-AudioVisualizer *
-AudioVisualizer::fromFile(const QString &filename)
-{
-    if (filename.isEmpty())
-        return nullptr;
-
-    Utils::RawImageData rawImage(Utils::DecoderOption{}, filename);
-    QImage img = QImage(rawImage.releasePixels(), rawImage.getWidth(), rawImage.getHeight(),
-                        rawImage.getWidth(), QImage::Format_Grayscale8,
-                        Utils::RawImageData::pixelsDeleter, rawImage.releasePixels())
-                     .mirrored(false, true);
-
-    auto *audioVisualizer = new AudioVisualizer;
-    audioVisualizer->printSpectrum(img);
-    return audioVisualizer;
-}

src/UI/AudioVisualizer.hh

@@ -6,6 +6,7 @@
 #endif
 
 #include "TimingView.hh"
+#include "../Lib/Audio.hh"
 #include <QWidget>
 #include <QString>
 
@@ -14,12 +15,26 @@ namespace Vivy
 class AudioVisualizer final : public QWidget {
     Q_OBJECT
 
+private:
+    static constexpr inline auto fftSampleDeleter = [](FFTSample *ptr) noexcept -> void {
+        if (ptr)
+            av_free(ptr);
+    };
+    static constexpr inline auto rdftContextDeleter = [](RDFTContext *ptr) noexcept -> void {
+        if (ptr)
+            av_rdft_end(ptr);
+    };
+    static constexpr inline auto pixelsDeleter = [](void *ptr) noexcept -> void {
+        if (ptr)
+            delete[](reinterpret_cast<uchar *>(ptr));
+    };
+    using FFTSamplePtr   = std::unique_ptr<FFTSample[], decltype(fftSampleDeleter)>;
+    using RDFTContextPtr = std::unique_ptr<RDFTContext, decltype(rdftContextDeleter)>;
+
 public:
-    explicit AudioVisualizer(QWidget *parent = nullptr) noexcept;
+    explicit AudioVisualizer(AudioContext::StreamPtr, QWidget *parent = nullptr);
     ~AudioVisualizer() noexcept = default;
 
-    [[nodiscard("allocated")]] static AudioVisualizer *fromFile(const QString &);
-
 public slots:
     void printSpectrum(QImage) noexcept;
 };

src/UI/VivyDocumentView.cc

@@ -53,19 +53,20 @@ VivyDocumentView::loadAudioView() noexcept
         std::shared_ptr<AudioSubDocument> audioDocument = document->getAudioSubDocument();
         qDebug() << "Create an audio vizualizer for the audio sub document"
                  << audioDocument->getFilePath();
-        visualizer = AudioVisualizer::fromFile(audioDocument->getFilePath());
-        if (visualizer == nullptr) {
+
+        if (AudioContext::StreamPtr stream = audioDocument->getDefaultStream();
+            (stream == nullptr) || (visualizer = new AudioVisualizer(stream)) == nullptr) {
             qCritical() << "Failed to create visualizer for" << audioDocument->getFilePath();
             return;
         }
 
         QVBoxLayout *layout = new QVBoxLayout(this);
-        if (visualizer != nullptr) {
-            qDebug() << "Add visualizer to the view";
-            layout->addWidget(visualizer);
-        }
+        layout->addWidget(visualizer);
+
         setLayout(layout);
-    } else {
+    }
+
+    else {
         qDebug() << "The document" << document->getName() << "is not AudioAble";
     }
 }