Latest release (August 2024)

Full list of changes in this release

Major Features

This release includes the following features:

• Image size scaled up when rendering presentations to PNG and JPEG
• Automatic rotation of JPEG images based on Exif Orientation tag
• Unlink table of contents in Word documents
• Introduced new performance-oriented conversion mode for CAD format family

Image size scaled up when rendering presentations to PNG and JPEG

When rendering presentations, such as Microsoft PowerPoint Presentation (PPTX) files, the Viewer utilizes the physical dimensions of slide size. For instance, when the presentation size in PowerPoint is 13.333 inches by 7.5 inches, the output PNG or JPEG image size will be calculated using the following formula:

Width = 13.333 * 576 / 8 = 960px Height = 7.5 * 576 / 8 = 540px

Here, the value 576 corresponds to the number of pixels per inch, and 8 is a scale factor.

Applying this formula results in an output image size of 960px x 540px, which may appear pixelated on modern screens. To enhance image quality, we scale the output JPEG or PNG image to Full HD resolution (1920x1080) proportionally by either image width or height.

So, the formulas for the same slide change to:

Width = (13.333 * 576 / 8) * F1 = 1920px Height = (7.5 * 576 / 8) * F2 = 1080px

Note that F1 and F2 both variables have value 2 in this case. F1 and F2 values are calculated based on the source slide width and height proportionally to fit size by width or height.

Removed obsolete members

com.groupdocs.viewer.options.PdfViewOptions#getJpgQuality()

This API has been removed. Please use the following code to set image quality:

PdfViewOptions viewOptions = new PdfViewOptions();
viewOptions.setPdfOptimizationOptions(new PdfOptimizationOptions());
viewOptions.getPdfOptimizationOptions().setCompressImages(true);
viewOptions.getPdfOptimizationOptions().setImageQuality(50);

Learn more about PDF optimization in Optimize the output PDF file topic.

com.groupdocs.viewer.options.PdfViewOptions#isOptimize()

This API has been removed. Please use the following code to apply spreadsheet-specific optimizations like grid lines optimization when rendering spreadsheets to PDF:

PdfViewOptions viewOptions = new PdfViewOptions();
viewOptions.setPdfOptimizationOptions(new PdfOptimizationOptions());
viewOptions.getPdfOptimizationOptions().setOptimizeSpreadsheets(true);

Learn more about rendering spreadsheets in Optimize spreadsheets in a PDF file

Automatic rotation of JPEG images based on Exif Orientation tag

GroupDocs.Viewer for Java automatically rotates and flips JPEG images based on Exif orientation metadata. This ensures that you always see images in the correct orientation, regardless of how they were captured or stored. For instance, GroupDocs.Viewer for Java automatically rotated the following image 180 degrees to display it correctly.

Unlink table of contents in Word documents

When rendering to HTML or PDF, you can set WordProcessingOptions#setUnlinkTableOfContents(…) to true to unlink table of contents. For HTML rendering, <a> tags with relative links will be replaced with <span> tags, removing functionality but preserving visual appearance. For PDF rendering, the table of contents will be rendered as plain text without links to document sections.

The code example below renders a Word document with table of contents as a plain text without links.

try (Viewer viewer = new Viewer("resume.docx")) {
    // Convert the document to HTML.
    HtmlViewOptions viewOptions = HtmlViewOptions.forEmbeddedResources();
    // Unlink table of contents.
    viewOptions.getWordProcessingOptions().setUnlinkTableOfContents(true);
    viewer.view(viewOptions);
}

The following image illustrates the result:

Introduced new performance-oriented conversion mode for CAD format family

By default, the GroupDocs.Viewer converts and renders all documents within CAD format family with the max possible quality. In case when the input CAD file (DWG, for example) is very complex, it may lead to quite significant processing time. Also, the size of the generated output HTML or image (vector or raster) also may be too heavy.

Starting from the version 24.8 the GroupDocs.Viewer introduces a new public property within the CadOptions class — the setEnablePerformanceConversionMode(...) boolean flag. By default it is set to false - the GroupDocs.Viewer behaves as in previous versions, preserving the maximum quality. But when setting its value to true, then the performance-oriented conversion mode is enabled, which leads to significantly lesser conversion time as well as lesser byte size of the output document.

Enabling this mode is pretty simple — just create an instance of the CadOptions class by using any of the CadOptions factory methods, and then set the value for the setEnablePerformanceConversionMode(...) property. Example is below:

try (Viewer viewer = new Viewer("input.dwg")) {
   HtmlViewOptions viewOptions = HtmlViewOptions.forEmbeddedResources("Output-Page#{0}.html");                    
   viewOptions.setCadOptions(CadOptions.forRenderingByWidth(1000));
   viewOptions.getCadOptions().setEnablePerformanceConversionMode(true);

   viewer.view(viewOptions);
}

If taking an ordinary DWG file as a sample, the comparison between “quality” and “performance” modes are the next:

Screenshot below illustrates the visual differences between these modes, default quality-oriented mode is on the left side, and the new performance-oriented mode is on the right side: