some feedback improvements

Author: mbellew

src/libprojectM/PCM.hpp

@@ -33,7 +33,7 @@
 
 
 // 1024 is more computationally intensive, but maybe better at detecting lower bass
-#define FFT_LENGTH 512
+#define FFT_LENGTH 1024
 
 
 class 

src/libprojectM/Renderer/BeatDetect.cpp

@@ -43,24 +43,24 @@ BeatDetect::BeatDetect(PCM *_pcm)
 
     this->vol_instant=0;
     this->vol_history=0;
-    for (unsigned y=0;y<80;y++)
+    for (unsigned y=0;y<BEAT_HISTORY_LENGTH;y++)
         this->vol_buffer[y]=0;
 
     this->beat_buffer_pos=0;
 
     this->bass_instant = 0;
     this->bass_history = 0;
-    for (unsigned y=0;y<80;y++)
+    for (unsigned y=0;y<BEAT_HISTORY_LENGTH;y++)
         this->bass_buffer[y]=0;
 
     this->mid_instant = 0;
     this->mid_history = 0;
-    for (unsigned y=0;y<80;y++)
+    for (unsigned y=0;y<BEAT_HISTORY_LENGTH;y++)
         this->mid_buffer[y]=0;
 
     this->treb_instant = 0;
     this->treb_history = 0;
-    for (unsigned y=0;y<80;y++)
+    for (unsigned y=0;y<BEAT_HISTORY_LENGTH;y++)
         this->treb_buffer[y]=0;
 
     this->treb = 0;
@@ -125,39 +125,39 @@ void BeatDetect::getBeatVals( float samplerate, unsigned fft_length, float *vdat
         bass_instant += (vdataL[i*2]*vdataL[i*2]) + (vdataR[i*2]*vdataR[i*2]);
     }
     bass_instant *= 100.0/(ranges[1]-ranges[0]);
-    bass_history -= bass_buffer[beat_buffer_pos] *.0125;
+    bass_history -= bass_buffer[beat_buffer_pos] * (1.0/BEAT_HISTORY_LENGTH);
     bass_buffer[beat_buffer_pos] = bass_instant;
-    bass_history += bass_instant *.0125;
+    bass_history += bass_instant * (1.0/BEAT_HISTORY_LENGTH);
 
     mid_instant = 0;
     for (unsigned i=ranges[1]+1 ; i<=ranges[2] ; i++)
     {
         mid_instant += (vdataL[i*2]*vdataL[i*2]) + (vdataR[i*2]*vdataR[i*2]);
     }
     mid_instant *= 100.0/(ranges[2]-ranges[1]);
-    mid_history -= mid_buffer[beat_buffer_pos] *.0125;
+    mid_history -= mid_buffer[beat_buffer_pos] * (1.0/BEAT_HISTORY_LENGTH);
     mid_buffer[beat_buffer_pos] = mid_instant;
-    mid_history += mid_instant *.0125;
+    mid_history += mid_instant * (1.0/BEAT_HISTORY_LENGTH);
 
     treb_instant = 0;
     for (unsigned i=ranges[2]+1 ; i<=ranges[3] ; i++)
     {
         treb_instant += (vdataL[i*2]*vdataL[i*2]) + (vdataR[i*2]*vdataR[i*2]);
     }
     treb_instant *= 90.0/(ranges[3]-ranges[2]);
-    treb_history -= treb_buffer[beat_buffer_pos] *.0125;
+    treb_history -= treb_buffer[beat_buffer_pos] * (1.0/BEAT_HISTORY_LENGTH);
     treb_buffer[beat_buffer_pos] = treb_instant;
-    treb_history += treb_instant *.0125;
+    treb_history += treb_instant * (1.0/BEAT_HISTORY_LENGTH);
 
     vol_instant  = (bass_instant + mid_instant + treb_instant) / 3.0f;
-    vol_history -= (vol_buffer[beat_buffer_pos])*.0125;
+    vol_history -= (vol_buffer[beat_buffer_pos])* (1.0/BEAT_HISTORY_LENGTH);
     vol_buffer[beat_buffer_pos] = vol_instant;
-    vol_history += (vol_instant)*.0125;
+    vol_history += vol_instant * (1.0/BEAT_HISTORY_LENGTH);
 
 //    fprintf(stderr, "%6.3f %6.2f %6.3f\n", bass_history/vol_history, mid_history/vol_history, treb_history/vol_history);
-    bass = bass_instant / fmax(0.0001, bass_history + 0.5*vol_history);
-    mid  =  mid_instant / fmax(0.0001,  mid_history + 0.5*vol_history);
-    treb = treb_instant / fmax(0.0001, treb_history + 0.5*vol_history);
+    bass = bass_instant / fmax(0.0001, 1.3 * bass_history + 0.2*vol_history);
+    mid  =  mid_instant / fmax(0.0001, 1.3 *  mid_history + 0.2*vol_history);
+    treb = treb_instant / fmax(0.0001, 1.3 * treb_history + 0.2*vol_history);
     vol = vol_instant / fmax(0.0001, 1.5f * vol_history);
 
     if ( projectM_isnan( treb ) ) {

src/libprojectM/Renderer/BeatDetect.hpp

@@ -37,6 +37,10 @@
 #include <cmath>
 
 
+// this is the size of the buffer used to determine avg levels of the input audio
+// the actual time represented in the history depends on FPS
+#define BEAT_HISTORY_LENGTH 80
+
 class DLLEXPORT BeatDetect
 {
 	public:
@@ -54,17 +58,20 @@ class DLLEXPORT BeatDetect
 		PCM *pcm;
 
 		/** Methods */
-		BeatDetect(PCM *pcm);
+		explicit BeatDetect(PCM *pcm);
 		~BeatDetect();
-		void initBeatDetect();
 		void reset();
 		void detectFromSamples();
 		void getBeatVals( float samplerate, unsigned fft_length, float *vdataL, float *vdataR );
+
+        // getPCMScale() was added to address https://github.com/projectM-visualizer/projectm/issues/161
+        // Returning 1.0 results in using the raw PCM data, which can make the presets look pretty unresponsive
+        // if the application volume is low.
 		float getPCMScale()
 		{
-			// added to address https://github.com/projectM-visualizer/projectm/issues/161
-			// Returning 1.0 results in using the raw PCM data, which can make the presets look pretty unresponsive
-			// if the application volume is low.
+			// the constant here just depends on the particulars of getBeatVals(), the
+			// range of vol_history, and what "looks right".
+			// larger value means larger, more jagged waveform.
 #ifdef WIN32
 // this is broken?
 #undef max
@@ -75,33 +82,21 @@ class DLLEXPORT BeatDetect
 
 	private:
 		int beat_buffer_pos;
-        float bass_buffer[80];
+        float bass_buffer[BEAT_HISTORY_LENGTH];
 		float bass_history;
         float bass_instant;
 
-		float mid_buffer[80];
+		float mid_buffer[BEAT_HISTORY_LENGTH];
         float mid_history;
 		float mid_instant;
 
-		float treb_buffer[80];
+		float treb_buffer[BEAT_HISTORY_LENGTH];
 		float treb_history;
 		float treb_instant;
 
-        float vol_buffer[80];
+        float vol_buffer[BEAT_HISTORY_LENGTH];
         float vol_history;
         float vol_instant;
-
-    //		/** Vars */
-//		float beat_buffer[32][80],
-//		beat_instant[32],
-//		beat_history[32];
-//		float beat_val[32],
-//		beat_att[32],
-//		beat_variance[32];
-//		int beat_buffer_pos;
-//		float vol_buffer[80],
-//		vol_instant;
-//		float vol_history;
 };
 
 #endif /** !_BEAT_DETECT_H */