/// <summary>
/// Constructor --- perform class level init.
/// </summary>
internal TriTone()
{
toneState = TriToneState.WaitingForSignal;
//textWriter = new StreamWriter( @"c:\dev\tritone.log" );
textWriter = null;
}
public ToneDetected Detect(
short [] samples,
Complex [] cdata,
FrequencyBin [] averageFrequencyBins,
FrequencyBin [] instantenousFrequencyBins,
int mS, // the number of mS since the beginning of the data stream
double maxFrequency // the frequency where the maximum energy occurs from fft
)
{
ToneDetected retval;
retval = ToneDetected.NONE;
double energy;
// in this method, we are assuming 20 % of the tone is enough to cause
// a hit. Then, 8 or 11 hits are required based on the duration of the
// particular portion of the tone we are detecting based on the specification of
// the SIT (Special Information Tone).
// note, 8000hz so we are doing 8 samples per mS
switch( toneState )
{
case TriToneState.WaitingForSignal:
energy = 0;
//for(int i = 0; i < 128; ++i)
//{
// energy += cdata[i].Re;
//}
for( int i = 0; i < samples.Length; ++i )
{
energy += Math.Abs( samples[i] );
}
if(energy > 0)
{
// need to check the data we currently have for the
// first part of the tri-tone signal.
if( (maxFrequency >= TriToneConstants.startTone1) &&
(maxFrequency <= TriToneConstants.endTone1) )
{
Console.WriteLine( "Moving to state 1: {0}", mS );
Log( "Moving to state1" );
missCount = 0;
toneState = TriToneState.Tone1;
hitCount = 1;
}
}
break;
case TriToneState.Tone1:
streamName = "TriTone1";
if( ( maxFrequency >= TriToneConstants.startTone1 ) &&
( maxFrequency <= TriToneConstants.endTone1 ) )
{
missCount = 0;
hitCount++;
Log( string.Format( "Maxfreq={0} hits={1}",
maxFrequency, hitCount ) );
if( hitCount == 7 )
{
//Console.WriteLine( "Moving to state 2: {0}", mS );
//toneState = TriToneState.Tone2;
//Log( "Moving to state2" );
//hitCount = 0;
//missCount = 0;
minHitsFound = true;
missCount = 0;
}
}
else
{
if( ( maxFrequency >= TriToneConstants.startTone2 ) &&
( maxFrequency <= TriToneConstants.endTone2 ) )
{
if( minHitsFound )
{
Console.WriteLine( "Moving to state 2: {0}", mS );
Log( "Moving to state2" );
toneState = TriToneState.Tone2;
hitCount = 1;
missCount = 0;
minHitsFound = false;
}
//else
//{
// if( missCount < 1 )
// {
// missCount++;
// }
//}
}
else
{
if( missCount < 1 )
{
missCount++;
}
else
{
hitCount = 0;
}
}
}
break;
case TriToneState.Tone2:
streamName = "TriTone2";
if( ( maxFrequency >= TriToneConstants.startTone2 ) &&
( maxFrequency <= TriToneConstants.endTone2 ) )
{
missCount = 0;
hitCount++;
Log( string.Format( "Maxfreq={0} hits={1}",
maxFrequency, hitCount ) );
if( hitCount == 7 )
{
//toneState = TriToneState.Tone3;
//Console.WriteLine( "Moving to state 3: {0}", mS );
//Log( "Moving to state3" );
//hitCount = 0;
//missCount = 0;
minHitsFound = true;
missCount = 0;
}
}
else
{
if( ( maxFrequency >= TriToneConstants.startTone3 ) &&
( maxFrequency <= TriToneConstants.endTone3 ) )
{
if( minHitsFound )
{
Console.WriteLine( "Moving to state 3: {0}", mS );
Log( "Moving to state3" );
toneState = TriToneState.Tone3;
hitCount = 1;
missCount = 0;
minHitsFound = false;
}
//else
//{
// toneState = TriToneState.NoTriTone;
//}
}
else
{
if( missCount < 1 )
{
missCount++;
}
else
{
hitCount = 0;
}
}
}
break;
case TriToneState.Tone3:
streamName = "TriTone3";
if( ( maxFrequency >= TriToneConstants.startTone3 ) &&
( maxFrequency <= TriToneConstants.endTone3 ) )
{
missCount = 0;
hitCount++;
Log( string.Format( "Maxfreq={0} hits={1}",
maxFrequency, hitCount ) );
if( hitCount == 7 )
{
Console.WriteLine( "Found Tri: {0}", mS );
retval = ToneDetected.TRITONE;
Log( "tone found" );
hitCount = 0;
}
}
else
{
if( missCount < 1 )
{
missCount++;
}
else
{
toneState = TriToneState.NoTriTone;
}
}
break;
// this case indicates there definately is not tritone in the signal.
case TriToneState.NoTriTone:
break;
case TriToneState.Done:
break;
default:
break;
}
return retval;
}
