We are considering using the setImageResample functionality in PdfSaveOptions during our spreadsheet-to-PDF conversion process:
pdfSaveOptions.setImageResample(50, 50);
The purpose of our application is to generate a PDF preview of the original spreadsheet for display purposes. While we understand that resampling images can reduce the file size and potentially improve performance when handling large files, we are uncertain about the trade-off between the time/resources required for the compression process and the overall benefits.
Specifically, we would like to know:
Does enabling image resampling significantly increase the conversion time or resource usage, especially for spreadsheets with a high number of images?
Are there scenarios where it might be more efficient to use the original images without resampling, considering the preview-only use case of our application?
Any recommendations or best practices for deciding when to enable image resampling during PDF conversion?
We would greatly appreciate any insights, benchmarks, or suggestions to help us make an informed decision.
When considering the use of the setImageResample functionality in PdfSaveOptions during spreadsheet-to-PDF conversion, there are several factors to keep in mind regarding performance and efficiency:
Impact on Conversion Time and Resource Usage: Enabling image resampling can indeed increase the conversion time and resource usage, particularly for spreadsheets that contain a large number of images. The resampling process requires additional processing to adjust the image dimensions and quality, which can lead to longer conversion times. However, the exact impact can vary based on the size and number of images, as well as the specifications of the system performing the conversion.
Scenarios for Using Original Images: In cases where the primary goal is to generate a preview of the spreadsheet, it may be more efficient to use the original images without resampling. If the images are already optimized for display and the file size is manageable, maintaining the original quality can enhance the visual fidelity of the preview. This is particularly relevant if the images are critical for understanding the content of the spreadsheet.
Best Practices for Image Resampling:
Evaluate Image Quality Needs: If high-quality images are essential for the preview, consider using the original images. If file size and performance are more critical, resampling may be beneficial.
Test Different Resampling Settings: Experiment with various resampling dimensions to find a balance between image quality and file size. For example, you might start with a moderate resampling setting (e.g., 300 DPI) and adjust based on the results.
Benchmark Performance: Conduct tests to measure the conversion time and file size with and without resampling. This will provide concrete data to inform your decision.
Here is a code example demonstrating how to set image resampling in Java:
import com.aspose.cells.PdfSaveOptions;
import com.aspose.cells.Workbook;
import AsposeCellsExamples.Utils;
public class ResampleImagesForExcelToPDFConversion {
public static void main(String[] args) throws Exception {
// The path to the documents directory.
String dataDir = Utils.getSharedDataDir(ResampleImagesForExcelToPDFConversion.class) + "TechnicalArticles/";
// Open an Excel file
Workbook workbook = new Workbook(dataDir + "Book1.xlsx");
// Instantiate the PdfSaveOptions
PdfSaveOptions pdfSaveOptions = new PdfSaveOptions();
// Set Image Resample properties
pdfSaveOptions.setImageResample(300, 70);
// Save the PDF file
workbook.save(dataDir + "ResampledOutput.pdf", pdfSaveOptions);
}
}
This example shows how to set the image resampling options before saving the workbook as a PDF. Adjust the parameters as needed based on your specific requirements.
By considering these factors and testing different configurations, you can make a more informed decision regarding the use of image resampling in your application.