PDF blurry export of charts

Hi,

I found this question several times in the internet, but no answer, whether this issue is resolved yet.

We need to convert pptx files (containing charts) to pdf. When we use Aspose to export presentations as pdf, all chart images are too blurry for our needs. I attached both pptx and pdf. As you can see, the charts are rendered much sharper in the original pptx than in the pdf. We cannot use Aspose, as long as the rendering quality is that low.

Is there any way to raise the quality of rendered charts? I tried some PdfOptions (jpeg quality to 100, setSufficientResolution(), etc.) but the quality did not change.

Presentation pres = new Presentation(is);

com.aspose.slides.PdfOptions opts = new com.aspose.slides.PdfOptions();

// Set Jpeg Quality
opts.setJpegQuality((byte) 100);

// Define behavior for meta files
opts.setSaveMetafilesAsPng(true);

// Set Text Compression level
opts.setTextCompression(com.aspose.slides.PdfTextCompression.Flate);

// Define the PDF standard
opts.setCompliance(com.aspose.slides.PdfCompliance.Pdf15);

// Save the presentation to PDF with specified options
pres.save(outputFilename, com.aspose.slides.SaveFormat.Pdf, opts);

Kind regards,
Frank Herbert

Hi Frank,

Thank you for sharing the files and sample code.

I have used the following code and the result is much better than the output shared by you. Please try it and let us know if it works fine for you.

Presentation pres = new Presentation(“d:\data\CUIReport.pptx”);

com.aspose.slides.PdfOptions opts = new com.aspose.slides.PdfOptions();

// Set Jpeg Quality
opts.setJpegQuality((byte)100);

// Define behavior for meta files
opts.setSaveMetafilesAsPng(true);

// Set Text Compression level
opts.setTextCompression(com.aspose.slides.PdfTextCompression.Flate);

// Define the PDF standard
opts.setCompliance(com.aspose.slides.PdfCompliance.Pdf15);

//Set Resolution
opts.setSufficientResolution(300);


// Save the presentation to PDF with specified options
pres.save(“d:\data\CUIReport.pdf”, com.aspose.slides.SaveFormat.Pdf, opts);

I have attached the generated PDF file as well for your reference.

Thanks & Regards,

Hi,

Thank you for your answer, but this did not change anything (see attached pdf).

Also, in your example, you have a another font (Arial instead of Frutiger, I guess) used in the chart, so it just seems as if the chart is sharper. In my opinion the chart in your pdf is as blurry as in mine. Still, the quality is not acceptable for our purposes (these pdf’s are for the board of managers of several banks).

Why is the chart even compressed at all? You seem to use a very low quality jpg renderer in the Aspose.Slides library. Why not insert the charts as PNG or GIF?

After some further investigation, it seems as if charts are rendered in very low resolution (they seem to ignore the setSufficientResolution(). Is it possible to render them in a higher resolution?

Kind regards,
Frank

Hi Frank,

Thank you for the feedback.

Please share the “Frutiger” font file with us to further investigate the issue. We will further check the issue at our end for improving the quality of the chart rendering.

Thanks & Regards,

Hi,

the Frutiger Font is licensed, so I’m not allowed to share it. But you get the same effect with any serife font (like Times New Roman). I attached the same pptx file using another font with the same result. Please check, if you get any better results with this presentation. (I attached CUI.pdf as generated by Aspose.Slides and CUIReport.pdf is the quality we need. You will notice several differences in both outputs).

I’d still like to know if it is possible to include the charts as an emf
or svg rendering in the pdf? Or exchange the jpeg compression algorithm
on my side? Do you offer a licensing policy with which we could get
access to the sources?

To further complicate things I saw that series in a pie chart with “no fill” (i.e. transparent) colors are rendered in a random color (I added a pie chart on a second slide) in the pdf.

We would very much like to use your library, but with its present quality this is not possible (we need those charts in a very high quality).

Also we are in kind of a hurry, as we have to make the decision within the next week…

Kind regards,
Frank

Hi Frank,

Thank you for the feedback.

I am able to reproduce your mentioned issue after testing with your shared presentation file. An issue has been registered in our issue tracking system with issue id: SLIDESJAVA-34447 to further check the quality of the rendered charts and how to enhance it . Second issue has been registered with issue id: SLIDESJAVA-34448 regarding the wrong fill style of the Pie chart.

Also, we don’t provide the source of the API under any license. Our development team will further look into these issue and you will be notified via this forum thread once the issue is fixed.

Thanks & Regards,

The issues you have found earlier (filed as SLIDESJAVA-34448) have been fixed in this update.


This message was posted using Notification2Forum from Downloads module by Aspose Notifier.

The issues you have found earlier (filed as SLIDESJAVA-34447) have been fixed in this update.


This message was posted using Notification2Forum from Downloads module by Aspose Notifier.
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