Fix quite a few bad bugs in the skew estimation.

diff --git a/estimate-skew.c b/estimate-skew.c
index 1c44f864ca9fed96a26f8c195edf7e70573741eb..d2991fc32cafe04f89a5d921951ee3afce2f8e7c 100644 (file)
--- a/estimate-skew.c
+++ b/estimate-skew.c
@@ -11,7 +11,7 @@ double frac(double x)
 double filter(double x)
 {
        static double l = 0.0;
-       l = 0.001 * x + 0.999 * l;
+       l = 0.01 * x + 0.99 * l;
        return l;
 }
 
@@ -58,8 +58,10 @@ int main(int argc, char **argv)
        double speed = 1.0;
 
        while (!feof(in1) && !feof(in2)) {
+               short refs;
+
                // read sample from reference
-               if (fread(&sample, sizeof(short), 1, in1) != 1) {
+               if (fread(&refs, sizeof(short), 1, in1) != 1) {
                        exit(0);
                }
 
@@ -75,14 +77,14 @@ int main(int argc, char **argv)
 
                // linear interpolation (works well since delta_p varies so slowly)
                double t = frac(p);
-               short intp_sample = prev_sample * (1.0 - t) + sample * t;
+               double intp_sample = prev_sample * (1.0 - t) + sample * t;
 
                // subtract the two samples and pull it through a filter. we assume
                // the sines are normalized for now (and that there's no dc skew)
-               double offset = -0.001 * filter(intp_sample - sample);
-               speed += offset;
+               double offset = filter(intp_sample - refs);
+               speed -= 0.00000001 * offset;
                fwrite(&speed, sizeof(double), 1, skew);
 
-               printf("%f (offset=%f)\n", speed, offset);
+               printf("%f (offset=%f)\n", speed, intp_sample - sample);
        }
 }