diff userProgramsTim/cutsignal.m @ 38:c2204b18f4a2 tip

End nov big change

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/userProgramsTim/cutsignal.m	Mon Nov 28 13:34:28 2011 +0000
@@ -0,0 +1,96 @@
+function outsignal = cutsignal(insignal,samplingfrequency,vocabularyset)
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+%   This function cuts the silence before and after the audiosignal
+%
+%  (c) Tim Jürgens, Medizinische Physik, Feb.2006
+%
+%  usage: outsignal = cutsignal(insignal,samplingfrequency,vocabularyset)
+%
+%   
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+% initial_energythreshold = 0.11;
+% final_energythreshold = 0.05;
+% 
+% % choose initial and final delay due to different vocabularysets
+% if (strcmp(vocabularyset,'f_f') > 0)
+%     initial_delay = 0.17; % the speech started delay seconds before trespassing threshold (default 0.01, for f_f: 0.17)
+%     final_delay = 0.2; %default 0.1, for f_f: 0.2
+% else
+%     initial_delay = 0.01; % the speech started delay seconds before trespassing threshold (default 0.01, for f_f: 0.2)
+%     final_delay = 0.1; %default 0.1, for f_f: 0.2
+% end
+% 
+% [initialsample_of_frame, energy] = compute_energy(insignal, samplingfrequency);
+% for i = 1:length(initialsample_of_frame)
+%     if (energy(i) > initial_energythreshold)
+%         initialsample = initialsample_of_frame(i)-samplingfrequency*initial_delay;
+%         break;
+%     end
+% end
+% 
+% time_inverted_energy = energy(end:-1:1); %turn signal around
+% time_inverted_initialsample = initialsample_of_frame(end:-1:1);
+% 
+% for i = 1:length(time_inverted_initialsample)
+%     if (time_inverted_energy(i) > final_energythreshold)
+%         finalsample = time_inverted_initialsample(i)+samplingfrequency*final_delay;
+%         break;
+%     end
+% end
+% 
+% if (finalsample > length(insignal))
+%     finalsample = length(insignal);
+% end
+% outsignal = insignal(initialsample:finalsample);
+
+if nargin < 3
+    vocabularyset = 'a_a'; %default vocabularyset
+end
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+initial_threshold = 0.15; %amplitude threshold for detection of speech
+final_threshold = 0.1;
+
+% choose initial and final delay due to different vocabularysets
+if (strcmp(vocabularyset,'f_f') > 0)
+    initial_delay = 0.2; % the speech started delay seconds before trespassing threshold (default 0.01, for f_f: 0.2)
+    final_delay = 0.2; %default 0.1, for f_f: 0.2
+else
+    initial_delay = 0.01; % the speech started delay seconds before trespassing threshold (default 0.01, for f_f: 0.2)
+    final_delay = 0.1; %default 0.1, for f_f: 0.2
+end
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+%cut signal with taking initial delay into account
+for(i = 1:length(insignal))
+    if (abs(insignal(i)) > initial_threshold)
+        initialsample = i - samplingfrequency*initial_delay;
+        break;
+    end
+end
+
+
+time_inverted_insignal = insignal(end:-1:1); %turn signal around
+% cut it with taking a final delay into account
+for(i = 1:length(time_inverted_insignal))
+    if (abs(time_inverted_insignal(i)) > final_threshold)
+        finalsample = i - samplingfrequency*final_delay;
+        break;
+    end
+end
+
+if (finalsample < 0)
+    finalsample = 0;
+end
+if (initialsample < 1)
+    initialsample = 1;
+end
+
+%% output %%%
+outsignal = insignal(initialsample:end-finalsample);
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