Implemented stereo audio recording.

include/SFML/Audio/SoundRecorder.hpp

@@ -144,6 +144,34 @@ class SFML_AUDIO_API SoundRecorder : AlResource
     ////////////////////////////////////////////////////////////
     const std::string& getDevice() const;
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Set the channel count of the audio capture device
+    ///
+    /// This method allows you to specify the number of channels
+    /// used for recording. Currently only 16-bit mono and
+    /// 16-bit stereo are supported.
+    ///
+    /// \param channelCount Number of channels. Currently only
+    ///                     mono (1) and stereo (2) are supported.
+    ///
+    /// \see getChannelCount
+    ///
+    ////////////////////////////////////////////////////////////
+    void setChannelCount(unsigned int channelCount);
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Get the number of channels used by this recorder
+    ///
+    /// Currently only mono and stereo are supported, so the
+    /// value is either 1 (for mono) or 2 (for stereo).
+    ///
+    /// \return Number of channels
+    ///
+    /// \see setChannelCount
+    ///
+    ////////////////////////////////////////////////////////////
+    unsigned int getChannelCount() const;
+
     ////////////////////////////////////////////////////////////
     /// \brief Check if the system supports audio capture
     ///
@@ -263,6 +291,7 @@ class SFML_AUDIO_API SoundRecorder : AlResource
     Time               m_processingInterval; ///< Time period between calls to onProcessSamples
     bool               m_isCapturing;        ///< Capturing state
     std::string        m_deviceName;         ///< Name of the audio capture device
+    unsigned int       m_channelCount;       ///< Number of recording channels
 };
 
 } // namespace sf
@@ -309,6 +338,12 @@ class SFML_AUDIO_API SoundRecorder : AlResource
 /// by calling setDevice() with the appropriate device. Otherwise
 /// the default capturing device will be used.
 ///
+/// By default the recording is in 16-bit mono. Using the
+/// setChannelCount method you can change the number of channels
+/// used by the audio capture device to record. Note that you
+/// have to decide whether you want to record in mono or stereo
+/// before starting the recording.
+///
 /// It is important to note that the audio capture happens in a
 /// separate thread, so that it doesn't block the rest of the
 /// program. In particular, the onProcessSamples virtual function

src/SFML/Audio/SoundBufferRecorder.cpp

@@ -63,7 +63,7 @@ bool SoundBufferRecorder::onProcessSamples(const Int16* samples, std::size_t sam
 void SoundBufferRecorder::onStop()
 {
     if (!m_samples.empty())
-        m_buffer.loadFromSamples(&m_samples[0], m_samples.size(), 1, getSampleRate());
+        m_buffer.loadFromSamples(&m_samples[0], m_samples.size(), getChannelCount(), getSampleRate());
 }
 
 

src/SFML/Audio/SoundRecorder.cpp

@@ -51,7 +51,8 @@ m_thread            (&SoundRecorder::record, this),
 m_sampleRate        (0),
 m_processingInterval(milliseconds(100)),
 m_isCapturing       (false),
-m_deviceName        (getDefaultDevice())
+m_deviceName        (getDefaultDevice()),
+m_channelCount      (1)
 {
 
 }
@@ -86,8 +87,11 @@ bool SoundRecorder::start(unsigned int sampleRate)
         return false;
     }
 
-    // Open the capture device for capturing 16 bits mono samples
-    captureDevice = alcCaptureOpenDevice(m_deviceName.c_str(), sampleRate, AL_FORMAT_MONO16, sampleRate);
+    // Determine the recording format
+    ALCenum format = (m_channelCount == 1) ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16;
+
+    // Open the capture device for capturing 16 bits samples
+    captureDevice = alcCaptureOpenDevice(m_deviceName.c_str(), sampleRate, format, sampleRate);
     if (!captureDevice)
     {
         err() << "Failed to open the audio capture device with the name: " << m_deviceName << std::endl;
@@ -180,8 +184,11 @@ bool SoundRecorder::setDevice(const std::string& name)
         m_isCapturing = false;
         m_thread.wait();
 
-        // Open the requested capture device for capturing 16 bits mono samples
-        captureDevice = alcCaptureOpenDevice(name.c_str(), m_sampleRate, AL_FORMAT_MONO16, m_sampleRate);
+        // Determine the recording format
+        ALCenum format = (m_channelCount == 1) ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16;
+
+        // Open the requested capture device for capturing 16 bits samples
+        captureDevice = alcCaptureOpenDevice(name.c_str(), m_sampleRate, format, m_sampleRate);
         if (!captureDevice)
         {
             // Notify derived class
@@ -210,6 +217,32 @@ const std::string& SoundRecorder::getDevice() const
 }
 
 
+////////////////////////////////////////////////////////////
+void SoundRecorder::setChannelCount(unsigned int channelCount)
+{
+    if (m_isCapturing)
+    {
+        err() << "It's not possible to change the channels while recording." << std::endl;
+        return;
+    }
+
+    if (channelCount < 1 || channelCount > 2)
+    {
+        err() << "Unsupported channel count: " << channelCount << " Currently only mono (1) and stereo (2) recording is supported." << std::endl;
+        return;
+    }
+
+    m_channelCount = channelCount;
+}
+
+
+////////////////////////////////////////////////////////////
+unsigned int SoundRecorder::getChannelCount() const
+{
+    return m_channelCount;
+}
+
+
 ////////////////////////////////////////////////////////////
 bool SoundRecorder::isAvailable()
 {
@@ -267,7 +300,7 @@ void SoundRecorder::processCapturedSamples()
     if (samplesAvailable > 0)
     {
         // Get the recorded samples
-        m_samples.resize(samplesAvailable);
+        m_samples.resize(samplesAvailable * getChannelCount());
         alcCaptureSamples(captureDevice, &m_samples[0], samplesAvailable);
 
         // Forward them to the derived class