Implement 24 bit support for WAV export (#3021)

Add a new value of "24 Bit Float" to the "Depth" combo box in the
project export dialog.

Add a new enum value to ProjectRenderer::Depth and extend the evaluation
of the different enum values in ProjectRenderer.

Add the new case of a depth of 24 to AudioFileWave and remove some
repetition with regards to SF_FORMAT_WAV in the code. It's only set once
now and then the depth is "added" in a switch statement.

include/ProjectRenderer.h

@@ -44,6 +44,7 @@ public:
 	enum Depths
 	{
 		Depth_16Bit,
+		Depth_24Bit,
 		Depth_32Bit,
 		NumDepths
 	} ;

src/core/ProjectRenderer.cpp

@@ -76,14 +76,30 @@ ProjectRenderer::ProjectRenderer( const Mixer::qualitySettings & _qs,
 		return;
 	}
 
-	bool success_ful = false;
+	int depth;
+	switch (_os.depth)
+	{
+	case Depth_16Bit:
+		depth = 16;
+		break;
+	case Depth_24Bit:
+		depth = 24;
+		break;
+	case Depth_32Bit:
+		depth = 32;
+		break;
+	default:
+		// If this line is reached the enum has been extended without taking care here
+		Q_ASSERT(false);
+	}
+
+	bool successful = false;
 	m_fileDev = fileEncodeDevices[_file_format].m_getDevInst(
-				_os.samplerate, DEFAULT_CHANNELS, success_ful,
+				_os.samplerate, DEFAULT_CHANNELS, successful,
 				_out_file, _os.vbr,
 				_os.bitrate, _os.bitrate - 64, _os.bitrate + 64,
-				_os.depth == Depth_32Bit ? 32 : 16,
-							Engine::mixer() );
-	if( success_ful == false )
+				depth, Engine::mixer() );
+	if( !successful )
 	{
 		delete m_fileDev;
 		m_fileDev = NULL;

src/core/audio/AudioFileWave.cpp

@@ -64,11 +64,20 @@ bool AudioFileWave::startEncoding()
 	m_si.sections = 1;
 	m_si.seekable = 0;
 
+	m_si.format = SF_FORMAT_WAV;
+
 	switch( depth() )
 	{
-		case 32: m_si.format = SF_FORMAT_WAV | SF_FORMAT_FLOAT; break;
-		case 16:
-		default: m_si.format = SF_FORMAT_WAV | SF_FORMAT_PCM_16; break;
+	case 32:
+		m_si.format |= SF_FORMAT_FLOAT;
+		break;
+	case 24:
+		m_si.format |= SF_FORMAT_PCM_24;
+		break;
+	case 16:
+	default:
+		m_si.format |= SF_FORMAT_PCM_16;
+		break;
 	}
 	m_sf = sf_open(
 #ifdef LMMS_BUILD_WIN32
@@ -88,7 +97,7 @@ void AudioFileWave::writeBuffer( const surroundSampleFrame * _ab,
 						const fpp_t _frames,
 						const float _master_gain )
 {
-	if( depth() == 32 )
+	if( depth() == 32 || depth() == 24 )
 	{
 		float *  buf = new float[_frames*channels()];
 		for( fpp_t frame = 0; frame < _frames; ++frame )

src/gui/dialogs/export_project.ui

@@ -86,16 +86,7 @@
            <property name="spacing">
             <number>6</number>
            </property>
-           <property name="leftMargin">
-            <number>0</number>
-           </property>
-           <property name="topMargin">
-            <number>0</number>
-           </property>
-           <property name="rightMargin">
-            <number>0</number>
-           </property>
-           <property name="bottomMargin">
+           <property name="margin">
             <number>0</number>
            </property>
            <item>
@@ -148,16 +139,7 @@
         <item>
          <widget class="QWidget" name="depthWidget" native="true">
           <layout class="QVBoxLayout">
-           <property name="leftMargin">
-            <number>0</number>
-           </property>
-           <property name="topMargin">
-            <number>0</number>
-           </property>
-           <property name="rightMargin">
-            <number>0</number>
-           </property>
-           <property name="bottomMargin">
+           <property name="margin">
             <number>0</number>
            </property>
            <item>
@@ -174,6 +156,11 @@
                <string>16 Bit Integer</string>
               </property>
              </item>
+             <item>
+              <property name="text">
+               <string>24 Bit Float</string>
+              </property>
+             </item>
              <item>
               <property name="text">
                <string>32 Bit Float</string>