Hi,
 Workbook workbook = new Workbook(filepath);  
 WorksheetCollection worksheetCollection = workbook.getWorksheets();  
 ImageOrPrintOptions imgOptions = new ImageOrPrintOptions();  
 imgOptions.setImageFormat(getImageFormat(ImageFormat.getPng());  
 imgOptions.setOnePagePerSheet(onePagePerSheet);  
 imgOptions.setHorizontalResolution(150);  
 imgOptions.setVerticalResolution(150);  
 imgOptions.setOnlyArea(areaOnly);  
 for (int i = 0; i < worksheetCollection.getCount(); i++) {  
      Worksheet worksheet = worksheetCollection.get(i);  
      SheetRender sr = new SheetRender(worksheet, imageOrPrintOptions);  
      for (int j = 0; j < sr.getPageCount(); j++) {  
           String imageFilePath = FileUtils.getAbsoluteFilePath(destinationFilePrefix + (noOfImages++), configurationInfo.getPreviewType().getType());  
           sr.toImage(j, imageFilePath);  
      }  
 }