1 /*  This file is part of the KDE project.

     2 

     3 Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 

     5 This library is free software: you can redistribute it and/or modify

     6 it under the terms of the GNU Lesser General Public License as published by

     7 the Free Software Foundation, either version 2.1 or 3 of the License.

     8 

     9 This library is distributed in the hope that it will be useful,

    10 but WITHOUT ANY WARRANTY; without even the implied warranty of

    11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    12 GNU Lesser General Public License for more details.

    13 

    14 You should have received a copy of the GNU Lesser General Public License

    15 along with this library.  If not, see <http://www.gnu.org/licenses/>.

    16 */

    17 

    18 #include "audiooutput.h"

    19 #include "mediaobject.h"

    20 

    21 #include <QtCore/qmath.h>

    22 

    23 QT_BEGIN_NAMESPACE

    24 

    25 namespace Phonon

    26 {

    27     namespace DS9

    28     {

    29         AudioOutput::AudioOutput(Backend *back, QObject *parent)

    30             : BackendNode(parent), m_currentIndex(0), m_crossfadeProgress(1.),

    31               m_device(-1), m_backend(back), m_volume(0.)

    32         {

    33         }

    34 

    35         AudioOutput::~AudioOutput()

    36         {

    37         }

    38 

    39         int AudioOutput::outputDevice() const

    40         {

    41             return m_device;

    42         }

    43 

    44         static const qreal log10over20 = qreal(0.1151292546497022842); // ln(10) / 20

    45 

    46         void AudioOutput::setVolume(qreal newVolume)

    47         {

    48             for(int i = 0; i < FILTER_COUNT; ++i) {

    49                 ComPointer<IBasicAudio> audio(m_filters[i], IID_IBasicAudio);

    50                 if (audio) {

    51                     const qreal currentVolume = newVolume * (m_currentIndex == i ? m_crossfadeProgress : 1-m_crossfadeProgress);

    52                     const qreal newDbVolume = (qMax(0., 1.-::log(::pow(currentVolume, -log10over20)))-1.) * 10000;

    53                     audio->put_Volume(qRound(newDbVolume));

    54                 }

    55             }

    56 

    57             if (m_volume != newVolume) {

    58                 m_volume = newVolume;

    59                 emit volumeChanged(newVolume);

    60             }

    61         }

    62 

    63         void AudioOutput::setCrossFadingProgress(short currentIndex, qreal progress)

    64         {

    65             m_crossfadeProgress = progress;

    66             m_currentIndex = currentIndex;

    67             setVolume(m_volume);

    68         }

    69 

    70         bool AudioOutput::setOutputDevice(const AudioOutputDevice & newDevice)

    71         {

    72             //stub implementation

    73             return setOutputDevice(newDevice.index());

    74         }

    75 

    76         qreal AudioOutput::volume() const

    77         {

    78             return m_volume;

    79         }

    80 

    81         bool AudioOutput::setOutputDevice(int newDevice)

    82         {

    83             if (newDevice == m_device) {

    84                 return true;

    85             }

    86 

    87             //free the previous one if it was already set

    88             for(int i = 0; i < FILTER_COUNT; ++i) {

    89                 const Filter &oldFilter = m_filters[i];

    90 

    91                 Filter newFilter = m_backend->getAudioOutputFilter(newDevice);

    92 

    93                 if (m_mediaObject && oldFilter && newFilter) {

    94                     m_mediaObject->switchFilters(i, oldFilter, newFilter);

    95                 }

    96 

    97                 m_filters[i] = newFilter; 

    98 

    99 

   100             }

   101 

   102             m_device = newDevice;

   103             setVolume(m_volume);

   104             return true;

   105         }

   106     }

   107 }

   108 

   109 QT_END_NAMESPACE

   110 

   111 #include "moc_audiooutput.cpp"