Changeset 430899e583d1ce72d6fb3fbf929006c61f7fdc23

Timestamp:

06/10/09 03:08:52 (3 years ago)

Author:

Nedko Arnaudov <nedko@…>

Children:

8e197ebe8ae3d781b8662f7840b931db5122cd7d

Parents:

19123e6624236b0f9c97a3e13df1a493436350c2

git-committer:

Nedko Arnaudov <nedko@arnaudov.name> / 2009-06-10T03:08:52Z+0300

Message:

Draw frequency response curves

Files:

• ui (modified) (11 diffs)

ui

@@ -3 +3 @@
 # Copyright (C) 2008,2009 Nedko Arnaudov <nedko@arnaudov.name>
 # Copyright (C) 2006 Leonard Ritter <contact@leonard-ritter.com>
+# Filter response code by Fons Adriaensen
 #
 # This program is free software; you can redistribute it and/or modify
@@ -26 +27 @@
 import xml.dom.minidom
 import cairo
-from math import pi, sin, cos, atan2, log
+from math import pi, sin, cos, atan2, log, sqrt, hypot, log10
 from colorsys import hls_to_rgb, rgb_to_hls
 import liblo
@@ -626 +627 @@
 
 class filter_band:
-    pass
+    def __init__(self):
+        self.fsamp = 48e3
+
+    def set_params(self, freq, bandw, gain):
+        freq_ratio = freq / self.fsamp
+        gain2 = pow(10.0, 0.05 * gain)
+        b = 7 * bandw * freq_ratio / sqrt(gain2)
+        self.gn = 0.5 * (gain2 - 1)
+        self.v1 = -cos(2 * pi * freq_ratio)
+        self.v2 = (1 - b) / (1 + b)
+        self.v1 *= (1 + self.v2)
+        self.gn *= (1 - self.v2)
+
+    def get_response(self, freq):
+        w = 2 * pi * (freq / self.fsamp)
+        c1 = cos(w)
+        s1 = sin(w)
+        c2 = cos(2 * w)
+        s2 = sin(2 * w)
+
+        x = c2 + self.v1 * c1 + self.v2
+        y = s2 + self.v1 * s1
+        t1 = hypot(x, y)
+        x += self.gn * (c2 - 1)
+        y += self.gn * s2
+        t2 = hypot(x, y)
+
+        #return t2 / t1
+        return 20 * log10(t2 / t1)
 
 class frequency_response(gtk.DrawingArea):
@@ -639 +668 @@
         self.color_value = gtk.gdk.Color(int(65535 * 0.8), int(65535 * 0.7), 0)
         self.color_mark = gtk.gdk.Color(int(65535 * 0.3), int(65535 * 0.3), int(65535 * 0.3))
+        self.color_sum = gtk.gdk.Color(int(65535 * 1.0), int(65535 * 1.0), int(65535 * 1.0))
         self.width = 0
         self.height = 0
         self.margin = 10
         self.db_range = 30
+        self.master_gain = 0.0
+        self.master_enabled = False
 
         self.filters = {}
@@ -678 +710 @@
         #print x
         return x
+
+    def get_freq(self, x):
+        width = self.width - 3.5 * self.margin
+        return 20 * pow(1000, (x - 2.5 * self.margin) / width)
 
     def get_y(self, db):
@@ -746 +782 @@
                 self.draw_db_grid(cairo_ctx, -db)
 
-        cairo_ctx.set_source_color(self.color_value)
+        curves = [[x, {}, self.master_gain, self.get_freq(x)] for x in range(int(self.get_x(20)), int(self.get_x(20e3)))]
+        #print repr(curves)
+
+        # calculate filter responses
         for label, filter in self.filters.items():
             if not filter.enabled:
                 continue
 
+            for point in curves:
+                db = filter.get_response(point[3])
+                point[1][label] = [self.get_y(db), db]
+
+        # calculate sum curve
+        for point in curves:
+            for label, filter_point in point[1].items():
+                point[2] += filter_point[1]
+            #print point
+
+        # draw filter curves
+        for label, filter in self.filters.items():
+            if not filter.enabled:
+                continue
+
+            cairo_ctx.set_source_color(filter.color)
+            cairo_ctx.move_to(curves[0][0], curves[0][1][label][0])
+            for point in curves:
+                cairo_ctx.line_to(point[0], point[1][label][0])
+            cairo_ctx.stroke()
+
+        if self.master_enabled:
+            # draw sum curve
+            cairo_ctx.set_source_color(self.color_sum)
+            cairo_ctx.set_line_width(2);
+            cairo_ctx.move_to(curves[0][0], self.get_y(curves[0][2]))
+            for point in curves:
+                cairo_ctx.line_to(point[0], self.get_y(point[2]))
+            cairo_ctx.stroke()
+
+        # draw base point markers
+        for label, filter in self.filters.items():
+            if not filter.enabled:
+                continue
+
+            cairo_ctx.set_source_color(self.color_value)
             x = self.get_x(filter.adj_hz.value)
             y = self.get_y(filter.adj_db.value)
+
             cairo_ctx.move_to(x, y)
             cairo_ctx.show_text(label)
             cairo_ctx.stroke()
 
-    def add_filter(self, label, adj_hz, adj_db, adj_bw):
+    def add_filter(self, label, adj_hz, adj_db, adj_bw, color):
         #print "filter %s added (%.2f Hz, %.2f dB, %.2f bw)" % (label, adj_hz.value, adj_db.value, adj_bw.value)
         filter = filter_band()
         filter.enabled = False
         filter.label = label
+        filter.color = color
+        filter.set_params(adj_hz.value, adj_bw.value, adj_db.value)
+        adj_hz.filter = filter
+        adj_db.filter = filter
+        adj_bw.filter = filter
         filter.adj_hz = adj_hz
         filter.adj_db = adj_db
@@ -784 +865 @@
     def on_value_change_request(self, adj):
         #print "adj changed"
+        adj.filter.set_params(adj.filter.adj_hz.value, adj.filter.adj_bw.value, adj.filter.adj_db.value)
+        self.invalidate_all()
+
+    def master_enable(self):
+        self.master_enabled = True;
+        self.invalidate_all()
+
+    def master_disable(self):
+        self.master_enabled = False;
+        self.invalidate_all()
+
+    def set_master_gain(self, gain):
+        self.master_gain = gain;
         self.invalidate_all()
 
@@ -952 +1046 @@
         port_index = 2
 
+        filter_colors = [gtk.gdk.Color(int(65535 * 1.0), int(65535 * 0.6), int(65535 * 0.0)),
+                         gtk.gdk.Color(int(65535 * 0.6), int(65535 * 1.0), int(65535 * 0.6)),
+                         gtk.gdk.Color(int(65535 * 0.0), int(65535 * 0.6), int(65535 * 1.0)),
+                         gtk.gdk.Color(int(65535 * 0.9), int(65535 * 0.0), int(65535 * 0.5))]
+
         for i in [0, 1, 2, 3]:
             band_frame = gtk.Frame("Band %d" % (i + 1))
@@ -981 +1080 @@
                 self.ports[port_index - 3]['adj'], # frequency
                 self.ports[port_index - 1]['adj'], # gain
-                self.ports[port_index - 2]['adj']) # bandwidth
+                self.ports[port_index - 2]['adj'], # bandwidth
+                filter_colors[i])
 
             band_frame.add(band_box)
@@ -1062 +1162 @@
         adj.label.set_text(text)
 
+        if adj.port['index'] == 1:
+            #print "Master gain = %.2f dB" % adj.get_value()
+            self.fr.set_master_gain(adj.get_value())
+
         if self.initator:
             #print adj.port, adj.get_value()
@@ -1074 +1178 @@
                 if band_no > 0:
                     self.fr.enable_filter(str(band_no))
+                else:
+                    self.fr.master_enable()
             else:
                 value = 0.0
                 if band_no > 0:
                     self.fr.disable_filter(str(band_no))
+                else:
+                    self.fr.master_disable()
             self.send_port_value(port_index + self.port_base, value)