com.pixelmed.scpecg
Class SCPECG

java.lang.Object
  com.pixelmed.scpecg.SCPECG

public class SCPECG
extends Object

A class to encapsulate an entire SCP-ECG object.

Typically this class would be used to read an SCP-ECG object from a file, and to do something with the decompressed waveform data values. For example:

try {                   
        BinaryInputStream i = new BinaryInputStream(new BufferedInputStream(new FileInputStream(arg[0])),false);        // always little endian
        SCPECG scpecg = new SCPECG(i,verbose);
        short[][] data = scpecg.getDecompressedRhythmData();
        BinaryOutputStream o = new BinaryOutputStream(new BufferedOutputStream(new FileOutputStream(arg[1])),false);    // little endian
        // write interleaved raw little endian data
        int numberOfChannels = data.length;
        int nSamplesPerChannel = data[0].length;        // assume all the same
        for (int sample=0; sample<nSamplesPerChannel; ++sample) {
                for (int lead=0;lead<numberOfChannels; ++lead) {
                        o.writeSigned16(data[lead][sample]);
                }
        }
        o.close();
}
catch (Exception e) {
        e.printStackTrace(System.err);
}
 

One might want to dump the entire contents of the instance as a string, as follows:

System.err.print(scpecg);
 

or perhaps to display the contents as a JTree:

ApplicationFrame af = new ApplicationFrame();
JScrollPane scrollPane = new JScrollPane();
SCPTreeBrowser browser = new SCPTreeBrowser(scpecg,scrollPane);
af.getContentPane().add(scrollPane);
af.pack();
af.setVisible(true);
 

Constructor Summary

SCPECG(BinaryInputStream i, boolean verbose)
Read an SCP-ECG object from an input stream.

Method Summary

short[][]	getDecompressedReferenceBeatData() Get the decompressed reference beat data.
short[][]	getDecompressedRhythmData() Get the decompressed rhythm data.
int	getDecompressedRhythmDataSampleTimeInterval() Get the sample time interval that will be applicable to the decompressed rhythm data.
String[]	getLeadNames() Get the names of the leads from Section 3.
int[]	getLeadNumbers() Get the numbers of the leads from Section 3.
String	getNamedField(String fieldName) Get the concatenated values of all the occurences of a named field from Section 1 as a String.
int	getNumberOfLeads() Get the number of leads.
long[]	getNumbersOfSamples() Get the number of samples for each lead.
Section1	getSection1()
Section10	getSection10()
Section8Or11	getSection11()
Section2	getSection2()
Section3	getSection3()
Section4	getSection4()
Section5Or6	getSection5()
Section5Or6	getSection6()
Section7	getSection7()
Section8Or11	getSection8()
Iterator	getSectionIterator() Get an Iterator over all the sections.
static void	main(String[] arg) For testing.
String	toString() Dump the object as a String.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

SCPECG

public SCPECG(BinaryInputStream i,
              boolean verbose)
       throws IOException

Read an SCP-ECG object from an input stream.

As errors are encountered, they are described on stderr.

The sections are also validated as they are read, and Section 0 is validated against the other sections.

Parameters:

i - the input stream (should have been opened as little endian)

verbose - if true, then the progress of the read is described

Throws:

IOException

Method Detail

getDecompressedRhythmData

public short[][] getDecompressedRhythmData()

Get the decompressed rhythm data.

This includes undecimating and adding in any reference beat.

Note that interpolation and filtering are NOT applied in the current implementation.

Returns:

arrays of samples for each lead

getDecompressedReferenceBeatData

public short[][] getDecompressedReferenceBeatData()

Get the decompressed reference beat data.

Returns:

arrays of samples for each lead

toString

public String toString()

Dump the object as a String.

Overrides:

toString in class Object

Returns:

the object as a String

getSection1

public Section1 getSection1()

getSection2

public Section2 getSection2()

getSection3

public Section3 getSection3()

getSection4

public Section4 getSection4()

getSection5

public Section5Or6 getSection5()

getSection6

public Section5Or6 getSection6()

getSection7

public Section7 getSection7()

getSection8

public Section8Or11 getSection8()

getSection10

public Section10 getSection10()

getSection11

public Section8Or11 getSection11()

getNumberOfLeads

public int getNumberOfLeads()

Get the number of leads.

Returns:

the number of leads

getNumbersOfSamples

public long[] getNumbersOfSamples()

Get the number of samples for each lead.

Returns:

an array of the number of samples for each lead

getDecompressedRhythmDataSampleTimeInterval

public int getDecompressedRhythmDataSampleTimeInterval()

Get the sample time interval that will be applicable to the decompressed rhythm data.

Note that this is the value after undecimation if the rhythm data was decimated; specifically in such cases it will be the sample time interval of the reference beat.

Returns:

the sample time interval in microSeconds

getNamedField

public String getNamedField(String fieldName)

Get the concatenated values of all the occurences of a named field from Section 1 as a String.

Returns:

the values as a String

getLeadNames

public String[] getLeadNames()

Get the names of the leads from Section 3.

Returns:

the names of the leads

getLeadNumbers

public int[] getLeadNumbers()

Get the numbers of the leads from Section 3.

Returns:

the numbers of the leads (using the codes in the standard and encoded in the data)

getSectionIterator

public Iterator getSectionIterator()

Get an Iterator over all the sections.

Returns:

an iterator of objects of type Section

main

public static void main(String[] arg)

For testing.

Parameters:

arg - one, two or three arguments, the input filename, optionally a output raw data filename, and optionally a text dump filename