Declined
Last Updated: 28 Nov 2016 08:20 by ADMIN
Jeff
Created on: 05 Mar 2015 19:51
Type: Feature Request
2
Pdf Export: Image compression
It would be nice to have an image filter option when exporting reports to PDF. For example we need to export an image to PDF using the "Flate" algorithm so that the image is not compressed in any way.
6 comments
ADMIN
Katia
Posted on: 17 Nov 2016 11:30
Hi Andy,

It appears that the issue is more likely related to Kendo UI PDF export functionality rather than to Telerik Reporting PDF rendering extension.

Please open a support ticket for Kendo UI and attach the demo project reproducing the problematic behavior so the support engineers from Kendo UI team can help you further on this matter.

Katia
Andy
Posted on: 15 Nov 2016 18:43
Thank you for your response, Peter!

We are using the RadPdfProcessing library. The specifics of the solution we have been trying to implement is as follows: we want to provide a "PDF export" option for our web-based reports that were built using a combination of Kendo grids and charts. Originally, the thought was to use the client-side PDF export feature built into Kendo, however, since that solution does not seem to be capable of exporting more than ~1000 rows, we started looking into doing server-side reporting. To that end, we played with 2 solutions. The first solution was using RadPDFProcessing, passing the output of imageDataURL from the client's browser back to the server to generate the report. We also worked on a solution that utilized the RadSheetProcessing library (which ultimately gave the best looking results). However, at the end of the day, the limitation appears to actually be what is getting exported out of the imageDataURL method itself. From what I can tell, it appears that the image generated by that method is being exported in 96dpi resolution, which when printed on a standard Letter-sized paper (resized horizontally to fit in portrait mode), the quality itself is simply not good enough (i.e., the writing on the charts look fuzzy, see the attached). This is true even after I was able to get the image to print in what appears to be mostly uncompressed format (i.e., printing the raw bitmap itself, only resizing to fit the print area). We also started looking into redrawing the SVG on the server-side using Inkscape, but honestly at this point the law of diminishing returns has us just about at the point of shelving this project for now. So any thoughts you have on how we might be able to implement this or if something obvious jumps out at you w/r/t anything we might be doing incorrectly, we're all ears.
Attached Files:
Andy
Posted on: 15 Nov 2016 18:15
deleted by andrew.waxman
ADMIN
Peter
Posted on: 14 Nov 2016 08:04
Hi Andy,

The thread is about the image compression and in my post I have explained that we keep the rendering extension image in its source format, however the blog is about the Adobe PDF reader display settings. 

Do you use Telerik Reporting or the RadPdfProcessing library? If you use Telerik Reporting please elaborate why you use the Kendo Chart instead of our data driven Graph? Generally the Telerik Reporting Graph is rendered using the target format vector elements.

Generally we will need more information, so please open a support thread and send us more information including the problematic image and the Adobe PDF reader settings that you use. 

Petar
Andy
Posted on: 11 Nov 2016 18:02
Peter, this blog entry from 7 years ago on your own website disagrees with you: 
http://www.telerik.com/blogs/the-strange-case-of-adobe-acrobat-or-why-do-images-in-telerik-reports-get-fuzzy-when-exported-to-pdf

Along with these forum posts:
http://www.telerik.com/forums/report-quality-on-print-and-export#mIlV2eobcUa48PjMf-j7dA
http://www.telerik.com/forums/renderreport-to-pdf-image-quality-problem

I, too, would like to see PDFs render in resolutions higher than 96dpi as I am also getting an unacceptable "fuzzy" result (even after trying the blog's suggested fix) when I embed an image (of a Kendo chart mind you) into a PDF report using the PdfFormatProvider and a RadFixedDocumentEditor. The image degradation makes the chart almost unreadable and is not an acceptable solution for our company's needs.
ADMIN
Peter
Posted on: 20 Sep 2016 08:26
Hi,

Generally the PDF rendering does not alter the images in any way if they are in PDF supported format and color space. Thus in order to investigate further, open a support thread and send us a sample report with image that reproduces the unexpected behavior.

Regards,
Petar