[xiph-commits] r11459 - trunk/ghost/libghost

[jm at svn.xiph.org]

Author: jm
Date: 2006-05-28 21:24:15 -0700 (Sun, 28 May 2006)
New Revision: 11459

Modified:
   trunk/ghost/libghost/sinusoids.c
Log:
comments on the prototypes


Modified: trunk/ghost/libghost/sinusoids.c
===================================================================
--- trunk/ghost/libghost/sinusoids.c	2006-05-29 04:13:12 UTC (rev 11458)
+++ trunk/ghost/libghost/sinusoids.c	2006-05-29 04:24:15 UTC (rev 11459)
@@ -28,6 +28,12 @@
 #define MIN(a,b) ((a)<(b) ? (a):(b))
 #define MAX(a,b) ((a)>(b) ? (a):(b))
 
+/* Find the sinusoids present in a frame -- THIS CAN BE IMPROVED
+ * psd is the power spectral density of the signal
+ * w are the returned sinudois frequencies (0 to pi)
+ * N is the max number of sinusoids (returns the actual number)
+ * length is the size of the psd
+ */
 void find_sinusoids(float *psd, float *w, int *N, int length)
 {
    int i,j;
@@ -144,6 +150,18 @@
    printf ("\n");
 }
 
+/* Models the signal as modulated sinusoids 
+ * x is the signal
+ * w are the frequencies
+ * window is the analysis window (you can use a rectangular window)
+ * ai are the cos(x) coefficients
+ * bi are the sin(x) coefficients
+ * ci are the x*cos(x) coefficients
+ * di are the x*sin(x) coefficients
+ * y is the approximated signal by summing all the params
+ * N is the number of sinusoids
+ * len is the frame size
+*/
 void extract_modulated_sinusoids(float *x, float *w, float *window, float *ai, float *bi, float *ci, float *di, float *y, int N, int len)
 {
    float cos_table[N][len];