GeneralEnvelope reqEnvelope = new GeneralEnvelope(originalEnvelope);
reqEnvelope.setEnvelope(239038.74625, 916916.62575, 253022.8255, 930900.705);
Stopwatch sw = new Stopwatch();
sw.start();
final GridCoverage2D coverage = readCoverage(reader, reqWidth, reqHeight, reqEnvelope);
assertNotNull("read coverage returned null", coverage);
RenderedImage image = coverage.getRenderedImage();