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-rw-r--r--Project/RTDSP/enhance.c55
1 files changed, 22 insertions, 33 deletions
diff --git a/Project/RTDSP/enhance.c b/Project/RTDSP/enhance.c
index 5422bcd..45a0060 100644
--- a/Project/RTDSP/enhance.c
+++ b/Project/RTDSP/enhance.c
@@ -80,11 +80,6 @@ DSK6713_AIC23_Config Config = { \
/**********************************************************************/
};
-typedef struct {
- float *pow;
- float sum;
-} MVal;
-
// Codec handle:- a variable used to identify audio interface
DSK6713_AIC23_CodecHandle H_Codec;
@@ -105,7 +100,8 @@ volatile int m_ptr = 0;
float lambda = 0.05;
float alpha = 100;
double avg = 0;
-MVal M[NUM_M];
+float *M[NUM_M];
+float mag_N_X;
float K;
static float time_constant = 40e-3; /* Time constant in ms */
int started = 0;
@@ -133,8 +129,10 @@ void main()
outwin = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
fft_out = (complex *) calloc(FFTLEN, sizeof(complex)); /* FFT Output */
power_in = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
- mag_in = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
lpf = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
+ mag_in = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
+ noise = (float *) calloc(FFTLEN, sizeof(float)); /* Output window */
+
/* initialize board and the audio port */
init_hardware();
@@ -152,12 +150,7 @@ void main()
outgain=OUTGAIN;
for (k = 0; k < NUM_M; ++k) {
- int i;
- M[k].pow = (float *) calloc(FFTLEN, sizeof(float));
- for(i = 0; i < FFTLEN; ++i) {
- M[k].pow[i] = MAX_FLOAT;
- }
- M[k].sum = MAX_FLOAT;
+ M[k] = (float *) calloc(FFTLEN, sizeof(float));
}
K = exp(-TFRAME/time_constant);
@@ -204,30 +197,29 @@ void init_HWI(void)
// Spectrum calculations for the new values
void write_spectrum(void) {
unsigned int k;
- M[m_ptr].sum = 0;
for(k = 0; k < FFTLEN; ++k) {
- if(power_in[k] < M[m_ptr].pow[k] && power_in[k] != 0) {
- M[m_ptr].pow[k] = power_in[k];
- M[m_ptr].sum += power_in[k];
- } else {
- M[m_ptr].sum += M[m_ptr].pow[k];
+ if(power_in[k] < M[m_ptr][k] || M[m_ptr][k] == 0) {
+ M[m_ptr][k] = power_in[k];
}
}
}
// Noise estimataion
void get_noise(void) {
- float min_sum = M[0].sum;
- int min_index = 0, k;
+ int k, i, min_i;
+ float min_val;
- for(k = 1; k < NUM_M; ++k) {
- if (M[k].sum < min_sum) {
- min_sum = M[k].sum;
- min_index = k;
+ for(k = 0; k < FFTLEN; ++k) {
+ min_i = 0;
+ min_val = M[0][k];
+ for(i = 1; i < NUM_M; ++i) {
+ if (M[i][k] < min_val && M[i][k]!= 0) {
+ min_val = M[i][k];
+ min_i = i;
+ }
}
+ noise[k] = alpha * M[min_i][k];
}
-
- noise = M[min_index].pow;
}
@@ -247,7 +239,6 @@ void process_frame(void)
{
int k, m;
int io_ptr0;
- float mag_N_X;
/* work out fraction of available CPU time used by algorithm */
cpufrac = ((float) (io_ptr & (FRAMEINC - 1)))/FRAMEINC;
@@ -282,7 +273,7 @@ void process_frame(void)
// calculate the power spectrum
for (k = 0; k < FFTLEN; ++k) {
- power_in[k] = pow(fft_out[k].r, 2) + pow(fft_out[k].i, 2);
+ power_in[k] = sqrt(fft_out[k].r * fft_out[k].r + fft_out[k].i * fft_out[k].i);
}
//low_pass_filter();
@@ -297,17 +288,15 @@ void process_frame(void)
int i;
frame_ctr = 0;
if(++m_ptr == NUM_M) m_ptr = 0;
- M[m_ptr].sum = 0;
for(i = 0; i < FFTLEN; ++i) {
- M[m_ptr].pow[i] = power_in[i];
- M[m_ptr].sum += power_in[i];
+ M[m_ptr][i] = power_in[i];
}
}
// max(lambda, |N(w)/g(w)|
for (k = 0; k < FFTLEN; ++k) {
float g;
- mag_N_X = sqrt(1 - alpha * noise[k]/power_in[k]);
+ mag_N_X = 1 - noise[k]/power_in[k];
g = mag_N_X > lambda ? mag_N_X : lambda;
fft_out[k] = rmul(g, fft_out[k]);
}