This file is indexed.

/usr/share/psychtoolbox-3/PsychObsolete/SoundTrigger.m is in psychtoolbox-3-common 3.0.11.20131230.dfsg1-1build1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
function SoundRecordingtest(duration)
% Basic test and demo of the sound recording/capture functionality of the
% new PsychSound() function.
%
% Parameters: duration = Recordingcapacity (in seconds) of the sound capture
% buffer. After recording of sound has been started, PsychSound will
% perform continuous recording into an internal ring-buffer with a storage capacity
% of 'duration' seconds, until recording gets stopped again. Soundrecording
% is done asynchronously as an automatic background process, independent of
% Matlabs/Psychtoolboxs execution. This way you can continue execution of
% your Matlab script (sound output, response collection, visual output,
% ...) while PsychSound is recording in the background. You can query the
% amount of new recorded sound data in the buffer and you can fetch this
% data from the buffer into a Matlab matrix at any time during of after
% recording. Be aware though that if the buffers capacity is exhausted, it
% will dispose old sound data to store new one - only the last 'duration'
% seconds of the most recently recorded sound are kept.
%
% This leaves you with two options:
%
% a) Request a buffer big enough to store the full duration of your
% recording from Start of capture until the end, and read out the recorded
% data into a Matlab matrix after the end of the recording. This is the
% most easy to implement (nice linear control flow Start->Stop->Fetch), but
% you have to know the maximum duration in advance, and you'll potentially
% use up significant amounts of memory.
%
% b) Request a buffer big enough to hold sound data for at least the
% duration of one iteration of your trial loop. During each iteration, poll
% and fetch portions of the recording into your Matlab matrix. More
% involved programming, but low memory consumption.
%
% With b) you can obviously also implement an audio recorder for infinite
% capture into a file via while(1) Waitabit; Poll&Fetch bit of sound data
% from PsychSound into Matrix; Append content of matrix to a file; end;
%
% And you can do live capture, manipulation & analysis of sound, e.g.,
% voice triggers, feedback of recorded sound to sound output and such.
%

try
   AssertOSX;
catch
	error('This demo does not work under M$-Windows yet, only on MacOS-X. Aborting...');   
end


% Initialize PsychSound for audio recording: We select a sampling frequency
% of 44100 Hz, (which would be also the default if left away) and a capture
% buffer size of 5 seconds. The 'recorderHandle' has the same function as
% the windowPtr for Screen()...
fprintf('Preparing for sound capture...\n');
recorderHandle = PsychSound('InitRecording', 44100, 5);

% Start asynchronous audio recording into capture buffer:
fprintf('Starting continous sound capture. Press a key to stop recording...\n');

while(1)
audiotrigger(0.5, recorderHandle);
[tonset tonset2 sounddata]=audiotrigger(0.5, recorderHandle);
tonset
tonset2
Snd('Play', sounddata, 44100);
WaitSecs(1);
end;

% Shut down sound recorder:
fprintf('Shutting down sound device...\n');
PsychSound('ShutdownRecording', recorderHandle);

return;


tstart = GetSecs;
PsychSound('StartRecording', recorderHandle);
startdelay = GetSecs - tstart

% We wait until keyboard press, while sound is recorded into PsychSounds
% internal buffer.
while(1)
    if KbCheck;
        break;
    end;
    sounddata = PsychSound('GetData', recorderHandle, 1024, 1, 0.001);
    if (max(sounddata)>0.5)
        break;
    end;
    %nrsamples = PsychSound('GetRecordingPosition', recorderHandle)
end;

tonset=GetSecs - tstart



% We stop the recording. The last 5 recorded seconds will be available for retrieval
tend=GetSecs;
PsychSound('StopRecording', recorderHandle);
enddelay=GetSecs - tend

fprintf('Recording stopped...\n');

% Ok, just for fun lets check how much sound data is available for
% retrieval. This could be 5 seconds, if recording lasted at least five
% seconds, so the buffer is full. Could be less if key was pressed earlier
% than 5 seconds. The returned value is the number of audio samples, aka
% nrsamples = availableamount_in_seconds * recordingfrequency = up to
% 5*44100 samples.
nrsamples = PsychSound('GetRecordingPosition', recorderHandle);
fprintf('%i samples have been recorded...\n', nrsamples);

% Now lets fetch everything that's available and return it as a Matlab
% matrix.
ttranss=GetSecs;
%sounddata = PsychSound('GetData', recorderHandle);
transferdelay=GetSecs - ttranss

nrsamples2 = size(sounddata, 1);

fprintf('%i samples have been returned to Matlab...\n', nrsamples2);

% Plot the soundwave as time-series:
plot(sounddata);
drawnow;

% Shut down sound recorder:
fprintf('Shutting down sound device...\n');
PsychSound('ShutdownRecording', recorderHandle);

if 1
    % Play the sound through good'ol SND command:
    for i=1:1
        fprintf('Playback!\n');
        Snd('Play', sounddata, 44100);
        if KbCheck
            break;
        end;
    end;
end;

% Done.
fprintf('Finished. Bye!\n');

return;




function [tonset , tonset2, sounddata] = audiotrigger(threshold, recorderHandle)
PsychSound('StartRecording', recorderHandle);
tstart = GetSecs;
startdelay = GetSecs - tstart;
samplecount=0;

% Wait for keyboard press or sound onset:
while(1)
    if KbCheck;
        break;
    end;
    
    sounddata = PsychSound('GetData', recorderHandle, 1024, 1, 0.001);
    tonset=GetSecs - tstart;
    if (max(sounddata)>threshold)
        break;
    else
        samplecount=samplecount + 1024;
    end;
end;
%samplecount
%min(find(sounddata > threshold))

tonset2=(samplecount + min(find(sounddata > threshold)))/44100;

% We stop the recording. The last 5 recorded seconds will be available for retrieval
tend=GetSecs;
PsychSound('StopRecording', recorderHandle);
%enddelay=GetSecs - tend

return;