Bitonal image scaling algorithms which improve the readability of bitonal, black and white images. Due to the lack of colors within the palette of 1-bit black and white images, they become splotchy and distorted when zoomed in or out

RadPdfViewer partially supports CCITTFaxDecode (that is basically TIFF). There are some limitations that are not supported at this stage like EncodedByteAlign = true or Group 3, 2-D encoding.

Customers are reporting an issue when trying to copy content in an application hosted on a remote machine (there are reports using TigerVNC and Citrix).  The exception is thrown from the Clipboard class with a message: OpenClipboard failed (Exception from HRESULT: 0x800401D0 (CLIPBRD_E_CANT_OPEN)).

It seems like such a behavior could be reproduced when the clipboard is already opened by another application. Here is a discussion on the matter: https://stackoverflow.com/questions/68666/clipbrd-e-cant-open-error-when-setting-the-clipboard-from-net

Fix available in LIB Version 2018.3.1029.

The hierarchical document structure is a means to describe the PDF document structure, which is currently not supported. See 10.6.1 Structure Hierarchy on 856 page of the PDF specification for details.
This document structure is an alternative to the standard PDF structure and most non-Adobe software does not support it.

The document might have been created with Adobe software like Adobe LiveCycle Designer. Very often the document contains some fallback text in the standard PDF structure like:
"Please wait... If this message is not eventually replaced by the proper contents of the document, your PDF viewer may not be able to display this type of document."
"The document you are trying to load requires Adobe Reader 8 or higher. You may not have the Adobe Reader installed or your viewing environment may not be properly configured to use Adobe Reader. For information on how to install Adobe Reader and configure your viewing environment please see  http://www.adobe.com/go/pdf_forms_configure."
"For the best experience, open this PDF portfolio in Acrobat X, Reader X, or later."

Add built-in localization for the UI control and its tooltips. Currently they can be localized by expanding the XAML of RadPdfViewerToolBar and adding the required resources to the code.

Add UI for adding comments and ability to save them. Comments are represented in the document model as text annotations (annotations with Subtype Text). 

The rendering of images with size ~5000/6000 and BitsPerComponent=1 is time-consuming. The scenario is optimized in terms of memory but would be nice to increase the performance as well.

At the moment the AnnotationsHandler, SelectionHandler and PanHandler cannot be removed or disabled. It would be convenient for this to be possible.

A similar scenario is not defined in the PDF specification but the widgets can be rendered as read-only fields despite the fields associated with them are missing.

At this point, the Print() method allowing the customers to silently print a document uses the PrintableAreaWidth and PrintableAreaHeight properties of the print dialog, which are read-only and cannot be changed through the API. Consider changing them with PrintTicket.PageMediaSize.

We should also consider the scenario when the client needs to print a smaller PDF page on a bigger page size. For instance, A5 page to be printed on an A4 sheet without scaling the content.

When importing documents containing Interactive FormFields with an empty collection of Normal state appearances, a NullReferenceException is thrown, which leads to non-editable FormFields in PdfViewer.

Fix available in LIB Version 2018.2.730.

Instead, we should not visualize them and they should not be interactable with the mouse.

Fix available in LIB Version 2018.2.730.

RadPdfViewer's AcroForm property ViewersShouldRecalculateWidgetAppearances should be respected when being set to true. In this case, RadPdfViewer should recalculate all widget appearances and this would resolve the issue with empty form field widgets after opening such PDF document.

When Find Next is used multiple times fast, and pages are still loaded asynchronously, sometimes NullReferenceException is thrown with the following call stack:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.GetLastCharacter()
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.IsLineBreak(Glyph glyph)
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.ProcessGlyph(Glyph glyph)
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.CreateTextPage(RadFixedPageInternal page)
   at Telerik.Windows.Documents.Fixed.Text.TextDocument.GetTextPage(Int32 index)
   at Telerik.Windows.Documents.Fixed.Search.KMPTextSearch.FindNext(TextDocument document, TextPosition startPosition, String searchText, Boolean matchCase, Boolean wholeWordsOnly)
   at Telerik.Windows.Documents.Fixed.Search.TextSearch.Find(String text, TextSearchOptions options)

...

The width values from the widths PDF property should be taken with priority compared to the font file calculations.

Fix available in R2 2018 SP1 release version.

Usually, the entries are on neighboring rows. However, some producers introduce some extra blank rows between entries and this causes exception in RadPdfViewer implementation.

Fix available in R2 2018 SP1 release version.

The issue is reproducible only on Windows XP. On newer versions of windows, the images are rendered as expected.

WORKAROUND: You may inherit DctDecode class in order to implement custom decoder. For instance, you may try calling DecodeWithJpegDecoder method from the base class as mentioned in the note of this documentation article:

http://docs.telerik.com/devtools/wpf/controls/radpdfviewer/customization-and-extensibility/customize-pdf-rendering

A sample implementation of these custom decoder may be seen below:

public class CustomDctDecode : DctDecode
{
    public override byte[] Decode(PdfObject decodedObject, byte[] inputData, DecodeParameters parms)
    {
        return DecodeWithJpegDecoder(inputData);
    }
}

When ScaleMode is set to FitToPage scrolling the Mousewheel or pressing the Arrow Down button does not produce immediate scroll. The page is scrolled to the next page after several scroll events/button presses are introduced.

Workaround: Provide custom ScrollCommand implementation.

Currently the minimal zoom out value is 0.8% which impacts the performance while scrolling large documents.

When graphic state uses stroking text rendering mode, the glyphs are visualized with bigger stroke thickness than the expected one.

Available in LIB Version 2018.2.521.