private void parseDataRecordStream(StreamReader sr)
{
//set the seek position in the file stream to the beginning of the data records.
sr.BaseStream.Seek((256 + this.Header.NumberOfSignalsInDataRecord * 256), SeekOrigin.Begin);
int dataRecordSize = 0;
foreach (EDFSignal signal in this.Header.Signals)
{
signal.SamplePeriodWithinDataRecord = this.Header.DurationOfDataRecordInSeconds / signal.NumberOfSamplesPerDataRecord;
dataRecordSize += signal.NumberOfSamplesPerDataRecord;
}
byte[] dataRecordBytes = new byte[dataRecordSize * 2];
while (sr.BaseStream.Read(dataRecordBytes, 0, dataRecordSize * 2) > 0)
{
EDFDataRecord dataRecord = new EDFDataRecord();
int j = 0;
int samplesWritten = 0;
foreach (EDFSignal signal in this.Header.Signals)
{
List <float> samples = new List <float>();
for (int l = 0; l < signal.NumberOfSamplesPerDataRecord; l++)
{
float value = (float)(((BitConverter.ToInt16(dataRecordBytes, (samplesWritten * 2)) + (int)signal.Offset)) * signal.AmplifierGain);
samples.Add(value);
samplesWritten++;
}
dataRecord.Add(signal.IndexNumberWithLabel, samples);
j++;
}
_dataRecords.Add(dataRecord);
}
}
public void LoadFromEdfFile(EDFFile file, EDFSignal signal, EDFSignal reference)
{
Label = signal.Label;
ReferenceLabel = reference?.Label ?? "mono";
SampleRate = signal.NumberOfSamplesPerDataRecord / file.Header.DurationOfDataRecordInSeconds;
int numberOfSamples = signal.NumberOfSamplesPerDataRecord * file.Header.NumberOfDataRecords;
Data = new float[numberOfSamples];
ViewAmplitude = 0.005F;
for (int i = 0; i < Data.Length; i++)
{
EDFDataRecord record = file.DataRecords[i / signal.NumberOfSamplesPerDataRecord];
float[] recordData = record[signal.IndexNumber];
if (reference == null)
{
Data[i] = recordData[i % signal.NumberOfSamplesPerDataRecord];
}
else
{
EDFDataRecord refRecord = file.DataRecords[i / signal.NumberOfSamplesPerDataRecord];
float[] refRecordData = refRecord[reference.IndexNumber];
Data[i] = recordData[i % reference.NumberOfSamplesPerDataRecord] - refRecordData[i % reference.NumberOfSamplesPerDataRecord];
}
}
}
// EDF File Parsing
/// <summary>
/// Modified From EDF library function https://edf.codeplex.com/SourceControl/latest#trunk/EDFFile.cs
/// Gets the signal samples from one period of time to another
/// </summary>
/// <param name="file"> The EDFFile class </param>
/// <param name="signal_to_retrieve"> The signal to get samples from </param>
/// <param name="StartTime"> The start time to get samples from </param>
/// <param name="EndTime"> The end time to get samples from </param>
/// <returns> A list of the retrieved samples </returns>
public static List <float> retrieveSignalSampleValuesMod(EDFFile file, EDFSignal signal_to_retrieve, DateTime StartTime, DateTime EndTime)
{
int start_sample, start_record;
int end_sample, end_record;
#region Find Start and End Points
// Duration of record in seconds
double record_duration = file.Header.DurationOfDataRecordInSeconds;
// Samples per record
double samples_per_record = signal_to_retrieve.NumberOfSamplesPerDataRecord;
// The sample period of the signal (Duration of Record)/(Samples per Record)
double sample_period = record_duration / samples_per_record;
{
// Time of start point in seconds
double total_seconds = (StartTime - file.Header.StartDateTime).TotalSeconds;
// Time of start point in samples
double total_samples = total_seconds / sample_period;
start_sample = ((int)(total_samples)) % ((int)samples_per_record); // Start Sample in Record
start_record = (int)((total_samples - start_sample) / samples_per_record); // Start Record
}
{
// Time of end point in seconds
double total_seconds = (EndTime - file.Header.StartDateTime).TotalSeconds;
// Time of end point in samples
double total_samples = total_seconds / sample_period - 1;
end_sample = ((int)total_samples) % ((int)samples_per_record); // End Sample in Record
end_record = (((int)total_samples) - end_sample) / ((int)samples_per_record); // End Record
}
#endregion
List <float> signalSampleValues = new List <float>();
if (file.Header.Signals.Contains(signal_to_retrieve))
{
for (int x = start_record; x <= end_record; x++)
{
EDFDataRecord dr = file.DataRecords[x];
foreach (EDFSignal signal in file.Header.Signals)
{
if (signal.IndexNumberWithLabel.Equals(signal_to_retrieve.IndexNumberWithLabel))
{
int start = x == start_record ? start_sample : 0;
int end = x == end_record ? end_sample : dr[signal.IndexNumberWithLabel].Count - 1;
for (int y = start; y <= end; y++)
{
signalSampleValues.Add(dr[signal.IndexNumberWithLabel][y]);
}
}
}
}
}
return(signalSampleValues);
}
/// <summary>
/// 解析数据
/// </summary>
/// <param name="sr"></param>
private void parseDataRecordStream(StreamReader sr)
{
//set the seek position in the file stream to the beginning of the data records.
sr.BaseStream.Seek((256 + this.Header.NumberOfSignalsInDataRecord * 256), SeekOrigin.Begin);
int dataRecordSize = 0;
foreach (EDFSignal signal in this.Header.Signals)
{
signal.SamplePeriodWithinDataRecord = (float)(this.Header.DurationOfDataRecordInSeconds / signal.NumberOfSamplesPerDataRecord);
dataRecordSize += signal.NumberOfSamplesPerDataRecord;
}
byte[] dataRecordBytes = new byte[dataRecordSize * 2];
while (sr.BaseStream.Read(dataRecordBytes, 0, dataRecordSize * 2) > 0)
{
EDFDataRecord dataRecord = new EDFDataRecord();
int j = 0;
int samplesWritten = 0;
foreach (EDFSignal signal in this.Header.Signals)
{
float refVoltage = signal.PhysicalMaximum;
List <float> samples = new List <float>();
for (int l = 0; l < signal.NumberOfSamplesPerDataRecord; l++)
{
// float value = (float)(((BitConverter.ToInt16(dataRecordBytes, (samplesWritten * 2)) + (int)signal.Offset)) * signal.AmplifierGain);
float value = (float)BitConverter.ToInt16(dataRecordBytes, (samplesWritten * 2));
if (this.Header.Version.Equals(NEURO_BOND_FLAG))
{
if (value >= 0 && value <= Math.Pow(2, 19) - 1)
{
value = refVoltage * value / (float)(Math.Pow(2, 19) - 1);
}
else
{
//value = refVoltage * ((value - (float)Math.Pow(2, 20)) / (float)(Math.Pow(2, 19) - 1));
value = refVoltage * value / (float)Math.Pow(2, 19);
}
}
value /= multiplyingPower;
samples.Add(value);
samplesWritten++;
}
dataRecord.Add(signal.IndexNumberWithLabel, samples);
j++;
}
_dataRecords.Add(dataRecord);
}
}