/// <summary>
/// Writes trace as a binary
/// </summary>
/// <param name="fs"></param>
public override void Write(FileStream fs)
{
if (Buffer != null)
{
for (int i = 0; i < Parameters.Count; i++)
{
SEGY_Constant c = (SEGY_Constant)Parameters[i];
string unit = ZebraHeaderDescription.c_Units[i];
switch (unit)
{
case "elevation":
ZebraHeaderDescription.SetElevationValue((float)c.ValueD, i + 1, Buffer);
break;
case "coordinate":
ZebraHeaderDescription.SetCoordinateValue((float)c.ValueD, i + 1, Buffer);
break;
case "ms":
ZebraHeaderDescription.SetTimeValue((float)c.ValueD, i + 1, Buffer);
break;
case "unitless":
default:
ZebraHeaderDescription.SetValue(c.Value, i + 1, Buffer);
break;
}
}
fs.Write(Buffer, 0, Buffer.Length);
}
}
/// <summary>
/// Creates a deep copy of this constant
/// </summary>
/// <returns></returns>
public override Oilfield_Constant Clone()
{
SEGY_Constant tmp = new SEGY_Constant();
tmp.Name = this.Name;
tmp.Unit = this.Unit;
tmp.Value = this.Value;
tmp.Description = this.Description;
return(tmp);
}
/// <summary>
/// Sets the SEGY parameter by name, adding a new parameter if necessary
/// Note that parameters represent the EBCDIC lines - any other paramenter beyond 40 will
/// not be saved.
/// </summary>
/// <param name="name">Constant name</param>
/// <param name="unit">Constant unit</param>
/// <param name="value">Constant value</param>
/// <param name="value">Description</param>
public override void SetParameter(string name, string unit, string value, string description)
{
foreach (SEGY_Constant c in Parameters)
{
if (c.Name != name)
{
continue;
}
c.Value = value;
return;
}
SEGY_Constant newP = new SEGY_Constant(name, unit, value, description);
Parameters.Add(newP);
}
/// <summary>
/// Constructor - creates from the parameters
/// </summary>
/// <param name="name">Variable name</param>
/// <param name="unit">Variable unit</param>
/// <param name="buffer">Buffer to parse</param>
/// <param name="readdata">if set to true, the data is also parsed</param>
public SEGY_Channel(string name, string unit, byte[] buffer, bool readdata)
: base(name, unit, "Seismic Trace")
{
PaddedWidth = 0;
for (int i = 0; i < ZebraHeaderDescription.c_Headers.Length; i++)
{
string value = "0";
name = ZebraHeaderDescription.c_Headers[i];
unit = ZebraHeaderDescription.c_Units[i];
switch (unit)
{
case "elevation":
value = ZebraHeaderDescription.GetElevationValue(i + 1, buffer).ToString("0.000");
break;
case "coordinate":
value = ZebraHeaderDescription.GetCoordinateValue(i + 1, buffer).ToString("0.00");
break;
case "ms":
value = ZebraHeaderDescription.GetTimeValue(i + 1, buffer).ToString("0.0");
break;
case "unitless":
default:
value = ZebraHeaderDescription.GetValue(i + 1, buffer);
break;
}
SEGY_Constant c = new SEGY_Constant(name, unit, value, "");
Parameters.Add(c);
}
if (!readdata)
{
return;
}
Buffer = new byte[buffer.Length];
Array.Copy(buffer, Buffer, Buffer.Length);
float[] Trace = ZebraHeaderDescription.GetTraceData(buffer);
foreach (float f in Trace)
{
Data.Add(Convert.ToDouble(f));
}
}
private void ParseFile(bool readdata)
{
FileStream fs = null;
try
{
fs = File.Open(FileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
fs.Read(EBCDICHeader, 0, EBCDICHeader.Length);
fs.Read(CommonHeader, 0, CommonHeader.Length);
for (int i = 0; i < 40; i++)
{
SEGY_Constant sc = new SEGY_Constant(i, EBCDICHeader);
Parameters.Add(sc);
}
Constants.Add(
new SEGY_Constant("JOB_ID", "", 0, SEGY_Constant.Int32, CommonHeader, "Job numeric identifier"));
Constants.Add(
new SEGY_Constant("LINE_NUMBER", "", 4, SEGY_Constant.Int32, CommonHeader, "Line number (Legacy use)"));
Constants.Add(
new SEGY_Constant("ACQUISITION_FILE_NUMBER", "", 8, SEGY_Constant.Int32, CommonHeader, "Reel number (Legacy use)"));
Constants.Add(
new SEGY_Constant("NBR_DATA_TRACE", "", 12, SEGY_Constant.Int16, CommonHeader, "Number of channels"));
Constants.Add(
new SEGY_Constant("NBR_AUX_TRACE", "", 14, SEGY_Constant.Int16, CommonHeader, "Number of aux channels"));
Constants.Add(
new SEGY_Constant("SAMPLING_PERIOD", "us", 16, SEGY_Constant.Int16, CommonHeader, "Sampling period in micro-seconds"));
Constants.Add(
new SEGY_Constant("SAMPLING_PERIOD_ORG", "us", 18, SEGY_Constant.Int16, CommonHeader, "Sampling period - as recorded"));
Constants.Add(
new SEGY_Constant("NSAMPLES", "", 20, SEGY_Constant.UInt16, CommonHeader, "Samples in each channel"));
Constants.Add(
new SEGY_Constant("FORMAT_CODE", "", 24, SEGY_Constant.Int16, CommonHeader, "1-IBM FP, 2-Int32, 3-Int16, 4-UTIG16 (Legacy use), 5-Real32"));
Constants.Add(
new SEGY_Constant("CDP_FOLD", "", 26, SEGY_Constant.Int16, CommonHeader, "CDP fold"));
Constants.Add(
new SEGY_Constant("SORT_CODE", "", 28, SEGY_Constant.Int16, CommonHeader, "1-as recorded, 2-CDP ensemble, 3-single fold, 4-stacked"));
Constants.Add(
new SEGY_Constant("VSUM", "", 30, SEGY_Constant.Int16, CommonHeader, "Number of vertical summations"));
Constants.Add(
new SEGY_Constant("SWEEP_START", "Hz", 32, SEGY_Constant.Int16, CommonHeader, "Sweep frequency start"));
Constants.Add(
new SEGY_Constant("SWEEP_STOP", "Hz", 34, SEGY_Constant.Int16, CommonHeader, "Sweep frequency end"));
Constants.Add(
new SEGY_Constant("SWEEP_LENGTH", "ms", 36, SEGY_Constant.Int16, CommonHeader, "Sweep length"));
Constants.Add(
new SEGY_Constant("SWEEP_TYPE", "", 38, SEGY_Constant.Int16, CommonHeader, "1-linear, 2-parabolic,3-exponential,4-other"));
Constants.Add(
new SEGY_Constant("SWEEP_CHANNEL", "", 40, SEGY_Constant.Int16, CommonHeader, "Trace number of sweep channel"));
Constants.Add(
new SEGY_Constant("SWEEP_TAPER_START", "ms", 42, SEGY_Constant.Int16, CommonHeader, "Sweep taper at start"));
Constants.Add(
new SEGY_Constant("SWEEP_TAPER_STOP", "ms", 44, SEGY_Constant.Int16, CommonHeader, "Sweep taper at end"));
Constants.Add(
new SEGY_Constant("SWEEP_TAPER_CODE", "", 46, SEGY_Constant.Int16, CommonHeader, "1-linear,2-cos-squared,3-other"));
Constants.Add(
new SEGY_Constant("CORRELATED_CODE", "", 48, SEGY_Constant.Int16, CommonHeader, "1-no,2-yes"));
Constants.Add(
new SEGY_Constant("BINARY_GAIN_RECOVERED", "", 50, SEGY_Constant.Int16, CommonHeader, "1-yes,2-no"));
Constants.Add(
new SEGY_Constant("AMPLITUDE_RECOVERED", "", 52, SEGY_Constant.Int16, CommonHeader, "1-no,2-spherical divergence,3-AGC,4-other"));
Constants.Add(
new SEGY_Constant("COORD_UNIT", "", 54, SEGY_Constant.Int16, CommonHeader, "Coordinates: 1-Metric(m), 2-Imperial(ft)"));
Constants.Add(
new SEGY_Constant("POLARITY_IMP", "", 56, SEGY_Constant.Int16, CommonHeader, "Impulse polarity code - response for pressure increase: 1-negative, 2- positive"));
Constants.Add(
new SEGY_Constant("POLARITY_VIB", "", 58, SEGY_Constant.Int16, CommonHeader, "Vibrator polarity code: 1-N,2-NE,3-E,4-SE,5-S,6-SW,7-W,8-NW"));
// Officially unused last part of the SEG-Y header
//for( int i=60; i<395; i+=4)
//{
// string t = i.ToString().PadLeft(3,'0');
// Constants.Add(
// new SEGY_Constant("TR"+t, "", i, SEGY_Constant.Int32, CommonHeader, "Trail " + t));
//}
long nsamples = Convert.ToInt64(GetConstant("NSAMPLES"));
double interval = Convert.ToDouble(GetConstant("SAMPLING_PERIOD")) / 1000.0;
if (interval <= 0.0)
{
SetConstant("SAMPLING_PERIOD", "1000");
interval = 1.0;
}
SEGY_Channel index = new SEGY_Channel("Time", "ms");
if (readdata)
{
for (int i = 0; i < nsamples; i++)
{
index.Data.Add(interval * i);
}
}
Channels.Add(index);
int format = Convert.ToInt32(GetConstant("FORMAT_CODE"));
long channelLength = 240;
switch (format)
{
case 3:
case 4:
channelLength += nsamples << 1; break;
case 1:
case 2:
case 5:
channelLength += nsamples << 2;
break;
default:
SetConstant("FORMAT_CODE", "1");
channelLength += nsamples << 2;
break;
}
byte[] Buffer = new byte[channelLength];
int traceCount = 0;
string globUnit = (GetConstant("COORD_UNIT") == "2") ? "ft" : "m";
while (true)
{
int read = fs.Read(Buffer, 0, Buffer.Length);
if (read < Buffer.Length)
{
break;
}
SEGY_Channel c = new SEGY_Channel(traceCount.ToString(), "sample", Buffer, readdata);
foreach (SEGY_Constant cc in c.Parameters)
{
if (cc.Unit == "unitless")
{
continue;
}
if (cc.Unit == "elevation")
{
cc.Unit = globUnit;
}
if (cc.Unit == "coordinate")
{
cc.Unit = globUnit;
}
if (cc.Unit == "velocity")
{
cc.Unit = globUnit + "/s";
}
}
this.Channels.Add(c);
traceCount++;
}
SetConstant("NBR_DATA_TRACE", traceCount.ToString());
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (fs != null)
{
fs.Close();
}
}
}
