commit 4b851d9ac3fb7023f39949122c43b5f73a676db4
parent 6263436911a0299afdd35f039fff5f583f17da5c
Author: Nasca Octavian PAUL <zynaddsubfx@yahoo.com>
Date: Wed, 2 Mar 2011 22:04:12 +0200
Started to implement onset detection
Diffstat:
3 files changed, 55 insertions(+), 5 deletions(-)
diff --git a/Stretch.cpp b/Stretch.cpp
@@ -142,6 +142,13 @@ void FFT::applywindow(FFTWindow type){
Stretch::Stretch(REALTYPE rap_,int bufsize_,FFTWindow w,bool bypass_,REALTYPE samplerate_,int stereo_mode_){
+ onset_detection_strength=0.0;
+
+
+#warning test
+ onset_detection_strength=0.5;
+
+
samplerate=samplerate_;
rap=rap_;
@@ -214,6 +221,44 @@ void Stretch::do_next_inbuf_smps(REALTYPE *smps){
};
};
+//static bool kuku=false;
+REALTYPE Stretch::do_detect_onset(){
+ //kuku=!kuku;
+ REALTYPE result=0.0;
+ if (onset_detection_strength>1e-3){
+ REALTYPE os=0.0,osinc=0.0;
+ REALTYPE osincold=1e-5;
+ int maxk=1+(int)(bufsize*500.0/(samplerate*0.5));
+ int k=0;
+ for (int i=0;i<bufsize;i++) {
+ osinc+=infft->freq[i]-old_freq[i];
+ osincold+=old_freq[i];
+ if (k>=maxk) {
+ k=0;
+ os+=osinc/osincold;
+ osinc=0;
+ };
+ k++;
+ };
+ os+=osinc;
+ if (os<0.0) os=0.0;
+ //if (os>1.0) os=1.0;
+
+ REALTYPE os_strength=pow(20.0,sqrt(1.0-onset_detection_strength))-1.0;
+ REALTYPE os_strength_h=os_strength*0.75;
+ if (os>os_strength_h){
+ result=(os-os_strength_h)/(os_strength-os_strength_h);
+ if (result>1.0) result=1.0;
+ };
+
+ //if (kuku) printf("%g\n",result);
+ //if (kuku) printf("(%g %g) %g => %g\n",os_strength,os_strength_h,os,result);
+
+ if (result>1.0) result=1.0;
+ };
+ return result;
+};
+
void Stretch::process(REALTYPE *smps,int nsmps){
if (bypass){
for (int i=0;i<bufsize;i++) out_buf[i]=smps[i];
@@ -228,6 +273,7 @@ void Stretch::process(REALTYPE *smps,int nsmps){
if (nsmps!=0){//new data arrived: update the frequency components
do_analyse_inbuf(smps);
if (nsmps==bufsize*2) do_analyse_inbuf(smps+bufsize);
+ REALTYPE onset=do_detect_onset();
};
diff --git a/Stretch.h b/Stretch.h
@@ -69,6 +69,10 @@ class Stretch{
return bufsize;
};
+ REALTYPE get_onset_detection_strength(){
+ return onset_detection_strength;
+ };
+
void process(REALTYPE *smps,int nsmps);
// virtual void process_output(REALTYPE *smps,int nsmps){};
@@ -80,6 +84,8 @@ class Stretch{
void set_rap(REALTYPE newrap);//set the current stretch value
+ void set_onset_detection_strength(REALTYPE detection_strength);
+
FFTWindow window_type;
protected:
int bufsize;
@@ -92,9 +98,10 @@ class Stretch{
void do_analyse_inbuf(REALTYPE *smps);
void do_next_inbuf_smps(REALTYPE *smps);
+ REALTYPE do_detect_onset();
// REALTYPE *in_pool;//de marimea in_bufsize
- REALTYPE rap;
+ REALTYPE rap,onset_detection_strength;
REALTYPE *old_out_smps;
REALTYPE *old_freq;
REALTYPE *new_smps,*old_smps,*very_old_smps;
diff --git a/readme.txt b/readme.txt
@@ -16,10 +16,6 @@ Requirements:
This algorithm/program is suitable only for extreme stretching the audio.
-There is lot room for improvements on this algorithm like:
- - on sharp attacks to make the window smaller and larger on steady sounds. This avoid adding constant sidebands on steady sounds and smoothing too much the sharp sounds.
- - even for small window, the sidebands produced can be lowered (how?)
-
Tips:
You can change the default output device with "PA_RECOMMENDED_OUTPUT_DEVICE" environment variable (used by PortAudio).
eg: set PA_RECOMMENDED_OUTPUT_DEVICE=1 #where 1 represents the index of the device; you can try other values for other devices
@@ -75,6 +71,7 @@ History:
2011????(2.)
- Added an option to preserve the tonal part or noise part
- Ignored the commandline parameters starting with "-" (usefull for macosx)
+ - Improved the algorithm
Enjoy! :)
Paul
