git status -u, learn something new every day.

libs/libcodec2/octave/codec2_demo.m

@@ -0,0 +1,108 @@
+% Copyright David Rowe 2012
+% This program is distributed under the terms of the GNU General Public License 
+% Version 2
+%
+% codec2_demo.m
+
+% Designed as an educational tool to explain the operation of Codec 2
+% for conference and user group presentations on a projector.  An
+% alternative to static overhead slides.
+%
+% Derived from codec2-dev/octave/plamp.m
+%
+% usage:
+%   octave:1> plamp("../src/hts2a",40)
+%
+% Then press:
+%   c - to cycle through the wavform being displayed on the figure
+%   n - next frame
+%   b - back one frame
+%
+%   tip: hold down n or b to animate the display
+%
+% The text files used as input are generated using c2sim:
+%
+%   /codec2-dev/src$ c2sim ../raw/hts2a.raw --dump hts2a
+%
+% The Codec 2 README explains how to build c2sim with dump files
+% enabled.
+
+function codec2_demo(samname, f)
+  
+  sn_name = strcat(samname,"_sn.txt");
+  Sn = load(sn_name);
+
+  sw_name = strcat(samname,"_sw.txt");
+  Sw = load(sw_name);
+
+  model_name = strcat(samname,"_model.txt");
+  model = load(model_name);
+  
+  figure(1);
+
+  k = ' ';
+  wf = "Sn";
+  do 
+   
+    if strcmp(wf,"Sn")
+      clf;
+      s = [ Sn(2*f-1,:) Sn(2*f,:) ];
+      plot(s);
+      axis([1 length(s) -20000 20000]);
+    end
+
+    if (strcmp(wf,"Sw"))
+      clf;
+      plot((0:255)*4000/256, Sw(f,:),";Sw;");
+    end
+  
+    if strcmp(wf,"SwAm")
+      Wo = model(f,1);
+      L = model(f,2);
+      Am = model(f,3:(L+2));
+      plot((0:255)*4000/256, Sw(f,:),";Sw;");
+      hold on;
+      plot((1:L)*Wo*4000/pi, 20*log10(Am),"+;Am;r");
+      axis([1 4000 -10 80]);
+      hold off;
+    end
+
+    if strcmp(wf,"Am")
+      Wo = model(f,1);
+      L = model(f,2);
+      Am = model(f,3:(L+2));
+      plot((1:L)*Wo*4000/pi, 20*log10(Am),"+;Am;r");
+      axis([1 4000 -10 80]);
+    end
+
+    % interactive menu
+
+    printf("\rframe: %d  menu: n-next  b-back  w-cycle window  q-quit", f);
+    fflush(stdout);
+    k = kbhit();
+    if (k == 'n')
+      f = f + 1;
+    end
+    if (k == 'b')
+      f = f - 1;
+    end
+    if (k == 'w') 
+      if strcmp(wf,"Sn")
+        next_wf = "Sw";
+      end
+      if strcmp(wf,"Sw")
+        next_wf = "SwAm";
+      end
+      if strcmp(wf,"SwAm")
+        next_wf = "Am";
+      end
+      if strcmp(wf,"Am")
+        next_wf = "Sn";
+      end
+      wf = next_wf;
+    end
+
+  until (k == 'q')
+  printf("\n");
+
+endfunction