topic Re: PDF document preview shows only blank sheet no text in Alfresco Forum

PDF document preview shows only blank sheet no text

dansiebert — Thu, 17 Feb 2022 12:25:06 GMT

I've recently been creating indexed PDF files with a Fujitsu ScanSnap iX1500 document scanner.
When I upload these PDFs to my Alfresco (Alfresco Community Build 201612, Alfresco Platform 5.2.d, Alfresco Share 5.2.c) and then want to view them, they are not displayed properly in the viewer. I only see a blank sheet. Shades from scanning (in shades of gray) can also sometimes be seen. However, if I use the magnifying glass to search in the preview, the search terms are found and on the sheet that is only displayed in white, the place where the word normally appears is marked in blue.
I can also mark the entire area on the sheet with the mouse and then transfer it to an editor via copy and paste. Then you have the text in the editor. The text is therefore present in the preview but is not displayed, only the background of the PDF document. What can be the reason?
The very small thumbnails in the file overview in a folder are OK.

regards
Daniel

Re: PDF document preview shows only blank sheet no text

angelborroy — Thu, 17 Feb 2022 14:45:28 GMT

Alfresco is using PDF.js for that (https://mozilla.github.io/pdf.js/).

Try those files on a recent Alfresco version to check if that ifxes the issue.

Re: PDF document preview shows only blank sheet no text

dansiebert — Fri, 18 Feb 2022 07:14:14 GMT

Thank you for the quick feedback. Yes, it works in a current environment (at my work). But at home I wanted to stay on the older version if possible, because it is so compact and not all components (web server, database,...) individually are installed. At that time I had chosen this all in one installation version (on Debian Linux). This is very beneficial for backup and recovery. It would be nice if I knew how to fix the error in the old version 5. Possibly only one binary needs to be exchanged.

Re: PDF document preview shows only blank sheet no text

angelborroy — Fri, 18 Feb 2022 08:35:07 GMT

You may try upgrading the PDFjs version in Alfresco 5, but not sure if that is doable.

Re: PDF document preview shows only blank sheet no text

bvalente — Tue, 22 Feb 2022 17:08:14 GMT

Hello,

I've the exact same problem in my Alfresco 5.2 instance.

Can you please give us some guidelines to update the pdf.js lib in this Alfresco instance?

I've already tried to update the share.war without success.

Thank you in advance!

Re: PDF document preview shows only blank sheet no text

dansiebert — Wed, 23 Feb 2022 09:02:19 GMT

Yes, I would also be interested in a procedure for updating pdf.js in ALfresco 5.2. I had started installing an up-to-date Alfresco using Docker. But putting the whole thing behind an Apache reverse proxy for SSL is impossibly complicated.

I would therefore like to stay with my 5.2 version, since I already have SSL access via proxy in operation.

Can anyone help with pdf.js update?

Thank you and best regards...

Re: PDF document preview shows only blank sheet no text

bvalente — Thu, 03 Mar 2022 16:06:01 GMT

@dansiebert,

The following topic helped me a lot to fix this issue:

https://hub.alfresco.com/t5/alfresco-content-services-forum/pdf-preview-issues-with-pdf-js-1-10-100-how-to-upgrade-share-to/m-p/309726

I've updated the pdfjs lib in Alfresco share.war to the latest version and applied the diff changes shown in the topic to PdfJs.js file.

I hope this can help you too.

Best Regards