// Start timing...
ServicePerformanceHelper sph = new ServicePerformanceHelper();
// Initialise what will be built:
List<PropertyComparison> props = new ArrayList<PropertyComparison>();
ServiceReport sr = null;
// Load the images.
BufferedImage i1;
BufferedImage i2;
try {
i1 = ImageIO.read( first.getContent().getInputStream() );
i2 = ImageIO.read( second.getContent().getInputStream() );
} catch (IOException e) {
return new CompareResult(null, ServiceUtils.createExceptionErrorReport("IOException reading the images. ", e));
}
if( i1 == null || i2 == null ) {
log.warning("One of the images was null when loaded!");
return new CompareResult(null, ServiceUtils.createErrorReport("Error reading the images, got a NULL."));
}
// Record time take to load the inputs into memory:
sph.loaded();
// Check comparison is possible: Are the dimensions the same?
if (i1.getWidth() != i2.getWidth() || i1.getHeight() != i2.getHeight()) {
// FIXME is this really an error, or rather a 'images are different' result?
return new CompareResult(null, ServiceUtils.createErrorReport("The image dimensions must match!"));
}
// FIXME Check comparison is sensible: are there the same number of channels? This is probably a WARNING?
if( i1.getColorModel().getNumComponents() != i2.getColorModel().getNumComponents()) {
System.out.println("The number of colour components does not match. "+i1.getColorModel().getNumComponents()+" != "+i2.getColorModel().getNumComponents());
log.warning("The number of colour components does not match. "+i1.getColorModel().getNumComponents()+" != "+i2.getColorModel().getNumComponents());
sr = new ServiceReport(ServiceReport.Type.WARN, ServiceReport.Status.SUCCESS, "Number of colour components was not the same. The missing channels, e.g. the alpha channel, will be assumed to be zero.");
// FIXME I think this should be more serious, as the results can be rather misleading.
// The comparison assumes the bit-mask to be zero everywhere, but this did not lead to such a bad PSNR?!
}
// Run the comparison:
double psnr = psnr(i1, i2);
props.add( buildPsnrProperty(psnr) );
// Create a happy service report if no problems occurred.
if( sr == null) {
// Also store some service properties:
sr = new ServiceReport(ServiceReport.Type.INFO, ServiceReport.Status.SUCCESS,
"Comparison succeeded.", sph.getPerformanceProperties() );
}
// Halt performance measurement:
sph.stop();