annotate modules-and-plug-ins/python-module/btrack_python_module.cpp @ 17:a31841af2bbc develop

Before this commit, the OnsetDetectionFunction class used double precision, and the BTrack class used floats. I have now made BTrack use double precision also. This works fine and the only cost of doing this is that we have to perform one array copy into floating point format so that sample rate conversion (which has to be in floating point format) can take place.

#include <iostream>
#include <Python.h>
#include "../../src/OnsetDetectionFunction.h"
#include "../../src/BTrack.h"
#include <numpy/arrayobject.h>

static PyObject * btrack_onsetdf(PyObject *dummy, PyObject *args) 
{
    PyObject *arg1=NULL;
    PyObject *arr1=NULL;
    
    if (!PyArg_ParseTuple(args, "O", &arg1)) 
    {
        return NULL;
    }
    
    arr1 = PyArray_FROM_OTF(arg1, NPY_DOUBLE, NPY_IN_ARRAY); 
    if (arr1 == NULL) 
    {
        return NULL;
    }


    
    ////////// GET INPUT DATA ///////////////////
    
    // get data as array
    double* data = (double*) PyArray_DATA(arr1);
    
    // get array size
    long signal_length = PyArray_Size((PyObject*)arr1);
    //int k = (int) theSize;
    
    // get data type 
    //char type = PyArray_DESCR(arr1)->type;
    
    ////////// BEGIN PROCESS ///////////////////
    int hsize = 512;
    int fsize = 1024;
    int df_type = 6;
    int numframes;
    double buffer[hsize];	// buffer to hold one hopsize worth of audio samples

    
    // get number of audio frames, given the hop size and signal length
	numframes = (int) floor(((double) signal_length) / ((double) hsize));
    
    OnsetDetectionFunction onset(hsize,fsize,df_type,1);

    double df[numframes];
    

    
    ///////////////////////////////////////////
	//////// Begin Processing Loop ////////////
	
	for (int i=0;i < numframes;i++)
	{		
		// add new samples to frame
		for (int n = 0;n < hsize;n++)
		{
			buffer[n] = data[(i*hsize)+n];
		}
		
		df[i] = onset.getDFsample(buffer);
		
	}
	
	///////// End Processing Loop /////////////
	///////////////////////////////////////////
    
    
    ////////// END PROCESS ///////////////////
    
    
    
    ////////// CREATE ARRAY AND RETURN IT ///////////////////
    int nd=1;
    npy_intp m= numframes;
    //double fArray[5] = {0,1,2,3,4};
    
    PyObject* c=PyArray_SimpleNew(nd, &m, NPY_DOUBLE);
    
    void *arr_data = PyArray_DATA((PyArrayObject*)c);
        
    memcpy(arr_data, df, PyArray_ITEMSIZE((PyArrayObject*) c) * m); 
    
     
    Py_DECREF(arr1);  
    Py_INCREF(Py_None); 
    //return Py_None;
    
    return (PyObject *)c;
    
    //return Py_BuildValue("c", type);
    //return Py_BuildValue("d", sum);
    //return Py_BuildValue("i", k);
/*    
fail:
    Py_XDECREF(arr1); 
    Py_XDECREF(arr2); 
    PyArray_XDECREF_ERR(oarr); 
    return NULL;*/
}


static PyObject * btrack_btrack(PyObject *dummy, PyObject *args) 
{
    PyObject *arg1=NULL;
    PyObject *arr1=NULL;
    
    if (!PyArg_ParseTuple(args, "O", &arg1)) 
    {
        return NULL;
    }
    
    arr1 = PyArray_FROM_OTF(arg1, NPY_DOUBLE, NPY_IN_ARRAY); 
    if (arr1 == NULL) 
    {
        return NULL;
    }
    
    
    
    ////////// GET INPUT DATA ///////////////////
    
    // get data as array
    double* data = (double*) PyArray_DATA(arr1);
    
    // get array size
    long signal_length = PyArray_Size((PyObject*)arr1);
    //int k = (int) theSize;
    
    // get data type 
    //char type = PyArray_DESCR(arr1)->type;
    
    ////////// BEGIN PROCESS ///////////////////
    int hsize = 512;
    int fsize = 1024;
    int df_type = 6;
    int numframes;
    double buffer[hsize];	// buffer to hold one hopsize worth of audio samples
    
    
    // get number of audio frames, given the hop size and signal length
	numframes = (int) floor(((double) signal_length) / ((double) hsize));
    
    OnsetDetectionFunction onset(hsize,fsize,df_type,1);
    BTrack b;
    
    b.initialise((int) hsize);	// initialise beat tracker
	
	// set parameters
    //b.setparams(0.9,5);
    
    double df[numframes];
    double beats[5000];
    int beatnum = 0;

    double df_val;
    
    ///////////////////////////////////////////
	//////// Begin Processing Loop ////////////
	
	for (int i=0;i < numframes;i++)
	{		
		// add new samples to frame
		for (int n = 0;n < hsize;n++)
		{
			buffer[n] = data[(i*hsize)+n];
		}
		
		df[i] = onset.getDFsample(buffer);
        
        df_val = df[i] + 0.0001;
                
		b.process(df_val);				// process df sample in beat tracker
		
		if (b.playbeat == 1)
		{
			beats[beatnum] = (((double) hsize) / 44100) * ((double) i);
			beatnum = beatnum + 1;	
		}
		
	}
	
	///////// End Processing Loop /////////////
	///////////////////////////////////////////
    
    
    ////////// END PROCESS ///////////////////
    
    double beats_out[beatnum];          // create output array
    
    // copy beats into output array
    for (int i = 0;i < beatnum;i++)     
    {
        beats_out[i] = beats[i];
    }
    
    
    
    ////////// CREATE ARRAY AND RETURN IT ///////////////////
    int nd=1;
    npy_intp m= beatnum;
    //double fArray[5] = {0,1,2,3,4};
    
    PyObject* c=PyArray_SimpleNew(nd, &m, NPY_DOUBLE);
    
    void *arr_data = PyArray_DATA((PyArrayObject*)c);
    
    memcpy(arr_data, beats_out, PyArray_ITEMSIZE((PyArrayObject*) c) * m); 
    
    
    Py_DECREF(arr1);  
    Py_INCREF(Py_None); 
    //return Py_None;
    
    return (PyObject *)c;
    
    //return Py_BuildValue("c", type);
    //return Py_BuildValue("d", sum);
    //return Py_BuildValue("i", k);
    /*    
     fail:
     Py_XDECREF(arr1); 
     Py_XDECREF(arr2); 
     PyArray_XDECREF_ERR(oarr); 
     return NULL;*/
}

static PyObject * btrack_btrack_df(PyObject *dummy, PyObject *args) 
{
    PyObject *arg1=NULL;
    PyObject *arr1=NULL;
    
    if (!PyArg_ParseTuple(args, "O", &arg1)) 
    {
        return NULL;
    }
    
    arr1 = PyArray_FROM_OTF(arg1, NPY_DOUBLE, NPY_IN_ARRAY); 
    if (arr1 == NULL) 
    {
        return NULL;
    }
    
    
    
    ////////// GET INPUT DATA ///////////////////
    
    // get data as array
    double* data = (double*) PyArray_DATA(arr1);
    
    // get array size
    long numframes = PyArray_Size((PyObject*)arr1);
    //int k = (int) theSize;
    
    // get data type 
    //char type = PyArray_DESCR(arr1)->type;
    
    ////////// BEGIN PROCESS ///////////////////
    int hsize = 512;

    BTrack b;
    
    b.initialise((int) hsize);	// initialise beat tracker
	
	// set parameters
    //b.setparams(0.9,5);
    
    double beats[5000];
    int beatnum = 0;
    double df_val;
    
    ///////////////////////////////////////////
	//////// Begin Processing Loop ////////////
	
	for (long i=0;i < numframes;i++)
	{		
        df_val = data[i] + 0.0001;
        
		b.process(df_val);				// process df sample in beat tracker
		
		if (b.playbeat == 1)
		{
			beats[beatnum] = (((double) hsize) / 44100) * ((double) i);
			beatnum = beatnum + 1;	
		}
		
	}
	
	///////// End Processing Loop /////////////
	///////////////////////////////////////////
    
    
    ////////// END PROCESS ///////////////////
    
    double beats_out[beatnum];          // create output array
    
    
    // copy beats into output array
    for (int i = 0;i < beatnum;i++)     
    {
        beats_out[i] = beats[i];
    }
    
    
    ////////// CREATE ARRAY AND RETURN IT ///////////////////
    int nd=1;
    npy_intp m= beatnum;
    //double fArray[5] = {0,1,2,3,4};
    
    PyObject* c=PyArray_SimpleNew(nd, &m, NPY_DOUBLE);
    
    void *arr_data = PyArray_DATA((PyArrayObject*)c);
    
    memcpy(arr_data, beats_out, PyArray_ITEMSIZE((PyArrayObject*) c) * m); 
    
    
    Py_DECREF(arr1);  
    Py_INCREF(Py_None); 
    //return Py_None;
    
    return (PyObject *)c;
    
    //return Py_BuildValue("c", type);
    //return Py_BuildValue("d", sum);
    //return Py_BuildValue("i", k);
    /*    
     fail:
     Py_XDECREF(arr1); 
     Py_XDECREF(arr2); 
     PyArray_XDECREF_ERR(oarr); 
     return NULL;*/
}



static PyMethodDef btrack_methods[] = {
    { "onsetdf",btrack_onsetdf,METH_VARARGS,"onset detection function"},
    { "btrack",btrack_btrack,METH_VARARGS,"beat tracker"},
    { "btrack_df",btrack_btrack_df,METH_VARARGS,"beat tracker with detection function input"},
    {NULL, NULL, 0, NULL} /* Sentinel */
};

PyMODINIT_FUNC initbtrack(void)
{
    (void)Py_InitModule("btrack", btrack_methods);
    import_array();
}

int main(int argc, char *argv[])
{
    /* Pass argv[0] to the Python interpreter */
    Py_SetProgramName(argv[0]);
    
    /* Initialize the Python interpreter.  Required. */
    Py_Initialize();
    
    /* Add a static module */
    initbtrack();
}