Add normalization gain factor to Export Analysis

libs/ardour/ardour/export_analysis.h

@@ -37,6 +37,8 @@ namespace ARDOUR {
 			, loudness_hist_max (0)
 			, have_loudness (false)
 			, have_dbtp (false)
+			, norm_gain_factor (1.0)
+			, normalized (false)
 			, n_channels (1)
 		{
 			memset (peaks, 0, sizeof(peaks));
@@ -53,6 +55,8 @@ namespace ARDOUR {
 			, loudness_hist_max (other.loudness_hist_max)
 			, have_loudness (other.have_loudness)
 			, have_dbtp (other.have_dbtp)
+			, norm_gain_factor (other.norm_gain_factor)
+			, normalized (other.normalized)
 			, n_channels (other.n_channels)
 		{
 			truepeakpos[0] = other.truepeakpos[0];
@@ -71,6 +75,8 @@ namespace ARDOUR {
 		int loudness_hist_max;
 		bool have_loudness;
 		bool have_dbtp;
+		float norm_gain_factor;
+		bool normalized;
 
 		uint32_t n_channels;
 		uint32_t freq[6]; // y-pos, 50, 100, 500, 1k, 5k, 10k [Hz]

libs/ardour/ardour/export_graph_builder.h

@@ -124,6 +124,7 @@ class LIBARDOUR_API ExportGraphBuilder
 		void add_child (FileSpec const & new_config);
 		void remove_children (bool remove_out_files);
 		bool operator== (FileSpec const & other_config) const;
+		void set_peak (float);
 
 	                                        private:
 		typedef boost::shared_ptr<AudioGrapher::SampleFormatConverter<Sample> > FloatConverterPtr;

libs/ardour/export_graph_builder.cc

@@ -332,6 +332,14 @@ ExportGraphBuilder::SFC::SFC (ExportGraphBuilder &parent, FileSpec const & new_c
 	}
 }
 
+void
+ExportGraphBuilder::SFC::set_peak (float gain)
+{
+	if (_analyse) {
+		analyser->set_normalization_gain (gain);
+	}
+}
+
 ExportGraphBuilder::FloatSinkPtr
 ExportGraphBuilder::SFC::sink ()
 {
@@ -476,7 +484,10 @@ ExportGraphBuilder::Normalizer::process()
 void
 ExportGraphBuilder::Normalizer::start_post_processing()
 {
-	normalizer->set_peak (peak_reader->get_peak());
+	const float gain = normalizer->set_peak (peak_reader->get_peak());
+	for (boost::ptr_list<SFC>::iterator i = children.begin(); i != children.end(); ++i) {
+		(*i).set_peak (gain);
+	}
 	tmp_file->seek (0, SEEK_SET);
 	tmp_file->add_output (normalizer);
 	parent.normalizers.push_back (this);

libs/audiographer/audiographer/general/analyser.h

@@ -41,8 +41,15 @@ class LIBAUDIOGRAPHER_API Analyser : public ListedSource<float>, public Sink<flo
 	void process (ProcessContext<float> const & c);
 	ARDOUR::ExportAnalysisPtr result ();
 
+	void set_normalization_gain (float gain) {
+		_result.normalized = true;
+		_result.norm_gain_factor = gain;
+	}
+
 	using Sink<float>::process;
 
+	static const float fft_range_db;
+
 	private:
 	float fft_power_at_bin (const uint32_t b, const float norm) const;
 

libs/audiographer/audiographer/general/normalizer.h

@@ -21,7 +21,7 @@ public:
 	~Normalizer();
 
 	/// Sets the peak found in the material to be normalized \see PeakReader \n RT safe
-	void set_peak (float peak);
+	float set_peak (float peak);
 
 	/** Allocates a buffer for using with const ProcessContexts
 	  * This function does not need to be called if

libs/audiographer/src/general/analyser.cc

@@ -21,6 +21,8 @@
 
 using namespace AudioGrapher;
 
+const float Analyser::fft_range_db (80); // dB
+
 Analyser::Analyser (float sample_rate, unsigned int channels, framecnt_t bufsize, framecnt_t n_samples)
 	: _ebur128_plugin (0)
 	, _dbtp_plugin (0)
@@ -196,12 +198,11 @@ Analyser::process (ProcessContext<float> const & c)
 	const framecnt_t x0 = _pos / _fpp;
 	framecnt_t x1 = (_pos + n_samples) / _fpp;
 	if (x0 == x1) x1 = x0 + 1;
-	const float range = 80; // dB
 
 	for (uint32_t i = 0; i < _fft_data_size - 1; ++i) {
 		const float level = fft_power_at_bin (i, i);
-		if (level < -range) continue;
-		const float pk = level > 0.0 ? 1.0 : (range + level) / range;
+		if (level < -fft_range_db) continue;
+		const float pk = level > 0.0 ? 1.0 : (fft_range_db + level) / fft_range_db;
 #if 0 // linear
 		const uint32_t y0 = floor (i * (float) height / _fft_data_size);
 		uint32_t y1 = ceil ((i + 1.0) * (float) height / _fft_data_size);

libs/audiographer/src/general/normalizer.cc

@@ -37,7 +37,7 @@ Normalizer::~Normalizer()
 }
 
 /// Sets the peak found in the material to be normalized \see PeakReader \n RT safe
-void Normalizer::set_peak (float peak)
+float Normalizer::set_peak (float peak)
 {
 	if (peak == 0.0f || peak == target) {
 		/* don't even try */
@@ -46,6 +46,7 @@ void Normalizer::set_peak (float peak)
 		enabled = true;
 		gain = target / peak;
 	}
+	return enabled ? gain : 1.0;
 }
 
 /** Allocates a buffer for using with const ProcessContexts