// Encode this image
log.debug("Encoding page" + (getCurrentPageNumber() + 1));
renderParams = PNGEncodeParam.getDefaultEncodeParam(image);
OutputStream os = getCurrentOutputStream(getCurrentPageNumber());
PNGImageEncoder encoder = new PNGImageEncoder(os, renderParams);
encoder.encode(image);
os.flush();
setCurrentPageNumber(getCurrentPageNumber() + 1);
}