File indexing completed on 2024-04-28 04:51:59

 /*
     SPDX-FileCopyrightText: 2012 Simon Andreas Eugster <simon.eu@gmail.com>
     This file is part of kdenlive. See www.kdenlive.org.
 
 SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 */
 
 #pragma once
 
 #include "audioInfo.h"
 #include <QFutureWatcher>
 #include <QObject>
 #include <memory>
 #include <mlt++/Mlt.h>
 #include <vector>
 
 class QImage;
 
 /**
   The audio envelope is a simplified version of an audio track
   with frame resolution. One entry is calculated by the sum
   of the absolute values of all samples in the current frame.
 
   See also: http://web.archive.org/web/20180626235917/http://bemasc.net/wordpress/2011/07/26/an-auto-aligner-for-pitivi/
   */
 class AudioEnvelope : public QObject
 {
     Q_OBJECT
 
 public:
     explicit AudioEnvelope(const QString &binId, int clipId, size_t offset = 0, size_t length = 0, size_t startPos = 0);
     ~AudioEnvelope() override;
     /**
        Starts the asynchronous computation that computes the
        envelope. When the computations are done, the signal
        'envelopeReady' will be emitted.
     */
     void startComputeEnvelope();
 
     /**
        Returns whether startComputeEnvelope() has been called.
     */
     bool hasComputationStarted() const;
 
     /**
        Returns the envelope data. Blocks until the computation of the
        envelope is done.
        REQUIRES: startComputeEnvelope() has been called.
     */
     const std::vector<qint64> &envelope();
 
     QImage drawEnvelope();
 
     size_t offset();
 
     void dumpInfo();
 
     int clipId() const;
     size_t startPos() const;
 
 private:
     struct AudioSummary
     {
         explicit AudioSummary(size_t size)
             : audioAmplitudes(size)
         {
         }
         AudioSummary() = default;
         // This is the envelope data. There is one element for each
         // frame, which contains the sum of the absolute amplitudes of
         // the audio signal for that frame.
         std::vector<qint64> audioAmplitudes;
         // Maximum absolute value of the elements in 'audioAmplitudes'.
         qint64 amplitudeMax = 0;
     };
 
     /**
        Blocks until the AudioSummary has been computed.
        REQUIRES: startComputeEnvelope() has been called.
     */
     const AudioSummary &audioSummary();
 
     /**
      Actually computes the envelope data, synchronously.
     */
     AudioSummary loadAndNormalizeEnvelope() const;
 
     std::shared_ptr<Mlt::Producer> m_producer;
     std::unique_ptr<AudioInfo> m_info;
     QFutureWatcher<AudioSummary> m_watcher;
     QFuture<AudioSummary> m_audioSummary;
 
     size_t m_offset;
     const int m_clipId;
     const size_t m_startpos;
     size_t m_envelopeSize;
 
 Q_SIGNALS:
     void envelopeReady(AudioEnvelope *envelope);
 };