bool SignatureImporter::execute(PlugInArgList* pInArgList, PlugInArgList* OutArgList)
{
VERIFY(pInArgList != NULL);
ProgressTracker progress(pInArgList->getPlugInArgValue<Progress>(Executable::ProgressArg()),
"Loading spectral signature", "spectral", "5A9F8379-7D7D-4575-B78B-305AE0DFC66D");
Signature* pSignature = pInArgList->getPlugInArgValue<Signature>(Importer::ImportElementArg());
VERIFY(pSignature != NULL);
DataDescriptor* pDataDescriptor = pSignature->getDataDescriptor();
VERIFY(pDataDescriptor != NULL);
FileDescriptor* pFileDescriptor = pDataDescriptor->getFileDescriptor();
VERIFY(pFileDescriptor != NULL);
progress.getCurrentStep()->addProperty("filename", pFileDescriptor->getFilename().getFullPathAndName());
DynamicObject* pMetadata = pSignature->getMetadata();
VERIFY(pMetadata != NULL);
string warningMsg;
LargeFileResource pSigFile;
VERIFY(pSigFile.open(pFileDescriptor->getFilename().getFullPathAndName(), O_RDONLY | O_BINARY, S_IREAD));
const Units* pUnits = pSignature->getUnits("Reflectance");
VERIFY(pUnits != NULL);
// Read the signature data
vector<double> wavelengthData, reflectanceData;
int64_t fileSize = pSigFile.fileLength();
bool readError = false;
size_t largeValueCount(0);
for (string line = pSigFile.readLine(&readError); readError == false; line = pSigFile.readLine(&readError))
{
if (isAborted())
{
progress.report("Importer aborted", 0, ABORT, true);
return false;
}
int64_t fileLocation = pSigFile.tell();
progress.report("Loading signature data", static_cast<int>(fileLocation * 100.0 / fileSize), NORMAL);
trim(line);
if (line.empty())
{
continue;
}
if (line.find('=') == string::npos)
{
double wavelength = 0.0, reflectance = 0.0;
vector<string> dataEntry;
split(dataEntry, line, is_space());
bool error = true;
if (dataEntry.size() >= 1)
{
wavelength = StringUtilities::fromXmlString<double>(dataEntry[0], &error);
if (wavelength > 50.0)
{
// Assume wavelength values are in nanometers and convert to microns
wavelength = Wavelengths::convertValue(wavelength, NANOMETERS, MICRONS);
}
}
if (!error && dataEntry.size() == 2)
{
reflectance = StringUtilities::fromXmlString<double>(dataEntry[1], &error);
// Since the signature file may not have contained info on units and unitScale (defaults to values of
// "REFLECTANCE" and "1.0"), we need to check that the reflectance value is properly scaled.
// In theory, a valid reflectance value should be between 0 and 1, but real data may extend beyond these
// limits due to errors that occurred in collection, calibration, conversion, etc. We're assuming that a
// value greater than 2.0 indicates that the value was scaled by a factor other than 1.0 - a common data
// collection practice is to store a data value as an integer value equal to the actual value multiplied
// by a scaling factor. This saves storage space while preserving precision. 10000 is a very common
// scaling factor and the one we will assume was used. Right now we'll just count the number of large values.
// If more than half the values are large, we will assume they were scaled and divide all the values by 10000.
if (pUnits->getUnitType() == REFLECTANCE && pUnits->getScaleFromStandard() == 1.0
&& fabs(reflectance) > 2.0)
{
++largeValueCount;
}
}
if (error)
{
progress.report("Error parsing signature data", 0, ERRORS, true);
}
wavelengthData.push_back(wavelength);
reflectanceData.push_back(reflectance);
}
}
if ((readError == true) && (pSigFile.eof() != 1))
{
progress.report("Unable to read signature file", 0, ERRORS, true);
return false;
}
// check for need to scale the values, i.e., at least half the values are large
if (reflectanceData.empty() == false && largeValueCount > 0 && largeValueCount >= (reflectanceData.size() / 2))
{
warningMsg += (warningMsg.empty() ? "" : "\n");
warningMsg += "Values appear to have been scaled - values have been divided by 10000";
for (vector<double>::iterator it = reflectanceData.begin(); it != reflectanceData.end(); ++it)
{
*it *= 0.0001; // divide by 10000
}
}
pSignature->setData("Wavelength", wavelengthData);
pSignature->setData("Reflectance", reflectanceData);
if (warningMsg.empty())
{
progress.report("Spectral signature loaded", 100, NORMAL);
}
else
{
progress.report(warningMsg, 100, WARNING);
progress.getCurrentStep()->addMessage(warningMsg, "spectral", "770EB61A-71CD-4f83-8C7B-E0FEF3D7EB8D");
}
progress.upALevel();
return true;
}
