Last Updated: 14 Nov 2019 16:26 by ADMIN
Created on: 07 Nov 2019 16:27
Category: PdfViewer
Type: Bug Report
Text not shown in PDFViewer


I'm using PDFViewer to display several documents in my application. Most of them are shown the right way, but there are others that appear "empty", or with some graphic elements but no text. I can see them perfectly with external third party viewers.

I've just downloaded and installed 2019.3.1022, but this issue remains.

I send some samples of PDF that are not showing.

Thank you in advance for your help.

Attached Files:
1 comment
Posted on: 14 Nov 2019 16:26

Hi Jorge,

Thank you for sharing the sample documents with us. It helped me to reproduce the issues you are currently encountering.

After taking a look I noticed that the 264624.pdf contains fonts with Descent property which have an invalid casing. In the PDF object model, property names are case sensitive. When a Descent property with an invalid casing is imported, the model of RadPdfViewer fails to load the FontDescriptor dictionary correctly, which leads to the issue with missing text content you are currently encountering. We have logged this in our feedback portal: missing text when importing font with not fully defined FontDescriptor, where you can subscribe to be notified for any status updates. 

I tested the 266129.pdf document you have provided I noticed that there is an invalid definition inside it - the start index of the cross-reference table contains a value of 1 while the value should be 0 according to the specification. At this point, RadPdfViewer doesn't handle such scenarios and we have logged a task to implement such a functionality. You can subscribe to the item if you would like to receive updates about changes in its status: Handle documents containing invalid cross-reference table start index. In the feedback item, you can find a sample project, which demonstrates a variant of how documents with an invalid cross-reference start index may be fixed.

In the 267030.pdf document, I noticed that contains text with Type 3 fonts. The import of Type 3 fonts is currently not supported by RadPdfViewer. We have logged a feature request in our feedback portal: Add support for Type 3 fonts, where you can vote to increase its priority and subscribe to be notified for any status updates. I am afraid that I couldn't find any workaround to provide you with.

In appreciation for pointing out this to our attention, I have increased your Telerik points.

I will proceed with changing the status of this item to Declined now as it is duplicated with the related items. However, I will stay available if any additional questions arise.

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