added matlab

2025-08-21 07:27:52 +02:00
parent fd522e1b99
commit 64c6745c76
50 changed files with 2516 additions and 0 deletions
@@ -0,0 +1,103 @@
+function eval_blit()
+
+sinc_use_lut = 1
+
+L = 40000;
+fs = 48000;
+fstart = 110;
+fend = 1100;
+df = (fend-fstart)/L;
+
+nhw = 4096;
+Hw = kaiser(nhw, 8)';
+
+if sinc_use_lut == 1
+    
+    nharm = 512;
+    nsin = 4096;
+    xx = (0:nsin)/nsin - 0.5;
+    mmm=0;
+    for mm=1:nharm,
+        mmm=mmm+1;
+        bb(mm, :) = sin(mmm*xx*pi);
+    end;
+    aa = sin(xx*pi);
+end;
+
+sinc_m(mm, find(aa == 0)) = 1;
+
+x = 0.5;
+z = -1;
+f = fstart;
+sqr = 0.0;
+c4 = 0;
+a = 1;
+b = 1;
+for n = 1:L,
+
+	if x >= 0.5,
+		x = x - 1;
+		p = fs/f;
+		fraq  = 1.0/p;
+		m = fix((p/2.0)) + 1;
+		saw = 0.0;
+		c3 = 0.0;
+		z = -z;
+	end;
+    if sinc_use_lut == 1
+        nn = (x+0.5)*nsin + 1;
+        ni = fix(nn);
+        nf = nn - ni;
+        bbi = (bb(m, ni+1) - bb(m, ni))*nf + bb(m, ni);     % Fractional delay (linear interpolation)
+        aai = (aa(ni+1) - aa(ni))*nf + aa(ni);              % Fractional delay (linear interpolation)
+        if (aai ~= 0)
+            blit = fraq* bbi / aai  * Hw(fix((x+0.5)*nhw)+1);
+        else
+            blit = fraq;
+        end
+    else
+        b = sin(m*x*pi);
+        a = sin(x*pi);
+        if (a ~= 0)
+            blit = fraq * b/a * Hw(fix((x+0.5)*nhw)+1);
+        else
+            blit = fraq;
+        end
+    end
+    
+	saw = saw + blit;
+	sqr = sqr + z*blit;
+	vsaw(n) = 2*(saw - c3);
+	vsqr(n) = 2*(sqr - 0.5);
+	vblit(n) = blit;
+    vc3(n) = b;
+	x = x + fraq;
+	c3 = c3 + fraq;
+	f = f + df;
+    c4 = c4 + fraq - blit;
+    vc4(n) = a;
+end;
+		
+
+close all
+
+figure;
+plot(1:L, vsaw, 1:L, vc4, 1:L, vblit); grid;
+
+figure;
+plot(vc4); grid;
+
+figure;
+plot(vc3); grid;
+
+if sinc_use_lut == 1
+    figure;
+    plot(sinc_m(nharm, :)); grid;
+end;
+
+wavwrite(0.5*vc4, fs, 'c4.wav');
+wavwrite(0.5*vc3, fs, 'c3.wav');
+wavwrite(0.5*vsqr, fs, 'sqr.wav');
+wavwrite(0.5*vsaw, fs, 'saw.wav');
+wavwrite(0.5*vblit, fs, 'blit.wav');
+