public int HRProcesssing(byte[] data, Size size)
{
if (Interlocked.Exchange(ref processing, 1) == 1)
{
return(-1);
}
int width = (int)size.Width;
int height = (int)size.Height;
double RedAvg;
double GreenAvg;
GreenAvg = ImageProcessing.DecodeYUV420SPtoRedBlueGreenAvg(ImageProcessing.Clone(data), height, width, 3); //1 stands for red intensity, 2 for blue, 3 for green
RedAvg = ImageProcessing.DecodeYUV420SPtoRedBlueGreenAvg(ImageProcessing.Clone(data), height, width, 1); //1 stands for red intensity, 2 for blue, 3 for green
GreenAvgList.Add(GreenAvg);
RedAvgList.Add(RedAvg);
++counter; //countes number of frames in 30 seconds
System.Diagnostics.Debug.WriteLine($"Processing {size.Width} {size.Height} red avg {RedAvg}");
//To check if we got a good red intensity to process if not return to the condition and set it again until we get a good red intensity
if (RedAvg < 200)
{
counter = 0;
//inc = 0;
//ProgP = inc;
//ProgO2.setProgress(ProgP);
Interlocked.Exchange(ref processing, 0);
}
long endTime = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
double totalTimeInSecs = (endTime - startTime) / 1000d; //to convert time to seconds
if (totalTimeInSecs >= 30)
{
startTime = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
SamplingFreq = (counter / totalTimeInSecs);
Double[] Green = GreenAvgList.ToArray();
Double[] Red = RedAvgList.ToArray();
SamplingFreq = (counter / totalTimeInSecs); //calculating the sampling frequency
double HRFreq = FFT(Green, counter, SamplingFreq); // send the green array and get its fft then return the amount of heartrate per second
double bpm = (int)Math.Ceiling(HRFreq * 60);
double HR1Freq = FFT(Red, counter, SamplingFreq); // send the red array and get its fft then return the amount of heartrate per second
double bpm1 = (int)Math.Ceiling(HR1Freq * 60);
if ((bpm > 45 || bpm < 200))
{
if ((bpm1 > 45 || bpm1 < 200))
{
bufferAvgB = (bpm + bpm1) / 2;
}
else
{
bufferAvgB = bpm;
}
}
else if ((bpm1 > 45 || bpm1 < 200))
{
bufferAvgB = bpm1;
}
else
{
bufferAvgB = bpm1;
}
Beats = (int)bufferAvgB;
}
if (Beats != 0)
{
}
if (RedAvg != 0)
{
// ProgP=inc++/34;;
// ProgO2.setProgress(ProgP);
}
Interlocked.Exchange(ref processing, 0);
return(Beats);
}
public int O2Processsing(byte[] data, Size size)
{
if (Interlocked.Exchange(ref processing, 1) == 1)
{
return(-1);
}
int width = (int)size.Width;
int height = (int)size.Height;
double RedAvg;
double BlueAvg;
RedAvg = ImageProcessing.DecodeYUV420SPtoRedBlueGreenAvg(ImageProcessing.Clone(data), width, height, 1); //1 stands for red intensity, 2 for blue, 3 for green
sumred = sumred + RedAvg;
BlueAvg = ImageProcessing.DecodeYUV420SPtoRedBlueGreenAvg(ImageProcessing.Clone(data), width, height, 2); //1 stands for red intensity, 2 for blue, 3 for green
sumblue = sumblue + BlueAvg;
RedAvgList.Add(RedAvg);
BlueAvgList.Add(BlueAvg);
++counter; //countes number of frames in 30 seconds
System.Diagnostics.Debug.WriteLine($"Processing {size.Width} {size.Height} red avg {RedAvg}");
//To check if we got a good red intensity to process if not return to the condition and set it again until we get a good red intensity
if (RedAvg < 200)
{
//inc = 0;
//ProgP = inc;
//ProgO2.setProgress(ProgP);
Interlocked.Exchange(ref processing, 0);
}
long endTime = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
double totalTimeInSecs = (endTime - startTime) / 1000d; //to convert time to seconds
//when 30 seconds of measuring passes do the following " we chose 30 seconds to take half sample since 60 seconds is normally a full sample of the heart beat
if (totalTimeInSecs >= 30)
{
startTime = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
SamplingFreq = (counter / totalTimeInSecs);
Double[] Red = RedAvgList.ToArray();
Double[] Blue = BlueAvgList.ToArray();
double HRFreq = FFT(Red, counter, SamplingFreq);
double bpm = (int)Math.Ceiling(HRFreq * 60);
double meanr = sumred / counter;
double meanb = sumblue / counter;
for (int i = 0; i < counter - 1; i++)
{
Double bufferb = Blue[i];
Stdb = Stdb + ((bufferb - meanb) * (bufferb - meanb));
Double bufferr = Red[i];
Stdr = Stdr + ((bufferr - meanr) * (bufferr - meanr));
}
double varr = Math.Sqrt(Stdr / (counter - 1));
double varb = Math.Sqrt(Stdb / (counter - 1));
double R = (varr / meanr) / (varb / meanb);
double spo2 = 100 - 5 * (R);
o2 = (int)(spo2);
if ((o2 < 80 || o2 > 99) || (bpm < 45 || bpm > 200))
{
//inc = 0;
//ProgP = inc;
//ProgO2.setProgress(ProgP);
//mainToast = Toast.makeText(getApplicationContext(), "Measurement Failed", Toast.LENGTH_SHORT);
//mainToast.show();
startTime = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
counter = 0;
Interlocked.Exchange(ref processing, 0);
return(-2);
}
}
if (o2 != 0)
{
}
if (RedAvg != 0)
{
// ProgP=inc++/34;;
// ProgO2.setProgress(ProgP);
}
Interlocked.Exchange(ref processing, 0);
return(o2);
}