/// <summary>
/// Default Constructor for DataSource.
/// If autoOutput, then this object will output one Sample every secondsPerStep
/// to its Followers; if not autoOutput, then it will only generate output when
/// requested by a call to trigger() or getNextValue() or getNextValues(int).
/// </summary>
/// <param name="secondsPerStep">Interval between samples, in seconds or fraction thereof,
/// e.g. 1 KHz = 1 ms per sample would have secondsPerStep = 0.001</param>
/// <param name="autoOutput">If true, then we push data out to the Followers;
/// if false, we wait for whoever to pull out the data</param>
public DataSource(double secondsPerStep, bool autoOutput)
{
// Set the interval:
stepSize = secondsPerStep;
// Set whether we output on a push or pull scheme:
autoSend = autoOutput;
if (autoSend)
{
// Init the TimerThread:
sendTimer = new TimerThread(
new System.Threading.ThreadStart(this.next),
true); // true -> wait for one call to complete before starting the next one
// false ); // false -> do NOT wait for one call to complete before starting the next one
// (this can cause overlaps and long queues of waiting threads if the
// code execution should halt for any reason, such as a msg. box or
// a debugger breakpoint).
}
// Make sure we init. this, otherwise we risk BIG problems!
// Note: each subclass should re-init lastOutput to what makes sense
// for that class.
lastOutput = DateTime.Now;
this.lastStep = 0;
this.lastOutput = DateTime.Now;
}
/// <summary>
/// Override default behavior to:
/// - Save a local copy
/// - Get file header info
/// - Update iData accordingly
/// - Allow using header info to drive the output rates
/// </summary>
public override void init(ChainInfo iData)
{
// Save a local handle:
// - If we're AutoSending, we're the authority on the data, so we can override the
// contents of iData. That means we point to iData and modify that.
// - If we're not AutoSending, we can tell anyone downstream what the actual data
// params are, but we shouldn't mess with the original iData to avoid affecting
// the source.
if (autoSend)
{ // Point to the input data structure:
initValues = iData;
}
else
{ // Make our own data structure:
initValues = new ChainInfo();
initValues.samplingPeriodSec = iData.samplingPeriodSec;
}
if (autoSend && doneReading) // We terminated the timer earlier - restart it:
{
// Init the TimerThread:
sendTimer = new TimerThread(
new System.Threading.ThreadStart(this.next),
false);
}
// Init. what needs it:
curReadStartPos = 0;
doneReading = false;
dataFinished = false; // in case it was set to true previously
if (initValues.patientInfo == null)
{
initValues.patientInfo = new PatientInfo("", "", "");
}
if (initValues.dataInfo == null)
{
initValues.dataInfo = new DataInfo( );
}
if (initValues.fileInfo == null)
{
initValues.fileInfo = new FileHandler( );
}
// Read the header from the input file:
readHeader();
// Init. the sampling period:
this.stepSize = initValues.samplingPeriodSec;
// Init output buffer:
initBuffer();
// Apply values and propagate downstream:
base.init(iData); // iData may have been changed or not
}
/// <summary>
/// Override default behavior to:
/// - Save a local copy
/// - Get file header info
/// - Update iData accordingly
/// - Allow using header info to drive the output rates.
/// <para>NOTE: This method call GC.Collect() to force garbage collection on the
/// managed-code environment. If you are running unmanaged code, before calling
/// this method you must ensure that your unmanaged storage allocations are properly
/// protected or released.</para>
/// </summary>
public override void init(ChainInfo iData)
{
string errMsg = null;
// Reset THOROUGHLY:
GC.Collect();
GC.WaitForPendingFinalizers();
WfdbAccess.CloseWfdb();
GC.Collect();
GC.WaitForPendingFinalizers();
// Read record header:
siArray = WfdbAccess.GetSigInfoArray(numSignals, ref errMsg);
bool result = WfdbAccess.GetSignalInfo(recordName, siArray, numSignals, ref errMsg);
if (!result)
{
//System.Windows.Forms.MessageBox("Unable to access header for record '" + recordName + "' in path '" + searchPath + "'!");
Exception ex = new ArgumentException("Unable to access header for record '" + recordName + "' in path '" + searchPath + "'.");
throw ex;
}
// Read useful info from header:
WFDB_Siginfo sigInfo = siArray.getitem(0);
buffSize = sigInfo.spf;
frameBuffer = new int[buffSize];
numSamples = sigInfo.nsamp * sigInfo.spf;
sigName = sigInfo.desc;
//sampFreq = WfdbAccess.GetSamplingFrequency(recordName);
//if (sampFreq < 1)
//{ // Problem reading header!
// //System.Windows.Forms.MessageBox("Unable to access record '" + recordName + "' in path '" + searchPath + "'!");
// Exception ex = new ArgumentException("Unable to access header for record '" + recordName + "' in path '" + searchPath + "'.");
// throw ex;
//}
adcZeroRef = sigInfo.adczero;
adcResBits = sigInfo.adcres;
adcMaxValue = (int)Math.Pow(2, adcResBits);
baseline = sigInfo.baseline;
ampGain = sigInfo.gain;
if (ampGain == 0)
{ // Use default:
ampGain = 200;
}
dataUnits = sigInfo.units;
if ((dataUnits == null) || (dataUnits.Length == 0))
{ // Assign arbitrarily?
dataUnits = "mV";
}
// Save a local handle:
if (autoSend)
{ // Point to the input data structure:
initValues = iData;
}
else
{ // Make our own data structure:
initValues = new ChainInfo();
initValues.samplingPeriodSec = iData.samplingPeriodSec;
}
if (autoSend && doneReading) // We previously terminated the timer - restart it:
{ // Init the TimerThread:
sendTimer = new TimerThread(
new System.Threading.ThreadStart(this.next),
true);
}
// Init. what needs it:
dispSamples = 0; // just started, nothing retrieved yet
doneReading = false;
if (initValues.patientInfo == null)
{
initValues.patientInfo = new PatientInfo("", "", "");
}
if (initValues.dataInfo == null)
{
initValues.dataInfo = new DataInfo(sigInfo.desc, DateTime.Now.ToString());
}
// And, apply the REAL values:
initValues.dataInfo.BitsPerSample = adcResBits;
initValues.dataInfo.ScaleMultiplier = ampGain.ToString();
if (adcResBits == 0)
{ // Missing some info -- go with a default:
initValues.dataInfo.FullScaleReferenceVoltage = "2.0";
initValues.dataInfo.ZeroOffset = "0.0";
initValues.dataInfo.ZeroReferenceVoltage = "-2.0";
}
else
{
initValues.dataInfo.FullScaleReferenceVoltage = ((adcMaxValue - baseline) / ampGain).ToString();
initValues.dataInfo.ZeroOffset = baseline.ToString();
initValues.dataInfo.ZeroReferenceVoltage = (-baseline / ampGain).ToString();
}
initValues.dataInfo.ValueUnits = dataUnits;
if (initValues.fileInfo == null)
{
initValues.fileInfo = new FileHandler();
}
if (initValues.samplingPeriodSec != stepSize)
{
// Update the sampling period:
initValues.samplingPeriodSec = stepSize;
}
//// Init. the sampling period:
//this.stepSize = initValues.samplingPeriodSec;
// Init output buffer:
ReadBuffer();
// Apply values and propagate downstream:
base.init(iData); // iData may have been changed or not
}
