SlideEx GetThumbnail() renders different than Slide GetThumbnail()

We are moving from 2003 to 2007 powerpoint and I’m noticing that the thumbnail processing is being handled differently between the 2 versions. Unfortunately it is not for the better in SlideEx version. Some Slides that correctly render in 2003 do not always in SlideEx. The code is identical (aside from one call being to Slide and the other to SlideEx).

Image imgFull = asposeSlide.GetThumbnail(1F, 1F);
var stream = new MemoryStream();
imgFull.Save(stream, ImageFormat.Jpeg);

The original presentation was converted from 2003 to 2007 format and looks fine when viewed in powerpoint. In fact, saving back to 2003 still looks same.

Out of 80 slides in one presentation, i’ve about 8-10% do not render properly.

Any ideas?



I have problem with blank images in the thumbnai in SlideEx. Sometimes I have a NullPointerException during getting of thumbnai. Image imgFull = asposeSlide.getThumbnail(1F, 1F);

PPT works fine

Hi Mobius,

Thanks for your interest in Aspose.Slides.

Well, slides rendering for MS PowerPoint 2007 (PPTX) formats was intrdouced in the recent releases of Aspose.Slides for .NET and Aspose.Slides for Java. We are in the improvement phase of this feature based on the issues reported by customers and our internal investigations. Every new release of Aspose.Slides comes up with enhancement of this feature.

For Aspose.Slides for Java, could you please provide the source presentation having slides with blank images where you are getting NullPointerException on using SlideEx.getThumbnail(1f,1f) so that the issue can be reproduced?

Thanks and Best Regards

Hello Aspose Dev Team:

We are facing same issue with 2007 PowerPoint pptx slides thumbnail rendering. The slide color is way off especially with color gradient. We are schedule to launch THIS WEEK and our application development is delayed - EVERY STEP while working with Aspose 2007 PowePoint components. Why is support for Aspose so slow?

We’re using Aspose since 2007. Aspose boasts how much you support 2007 PowerPoint but most are not documented and “Falls Short” on support. This is costing me more than what I budgeted for this project. If I were to write an review of you product and support and I would give you *** instead of *****. I would rather give you ***** which is what I expect from a Product leader like Aspose should deserve. Please Help!

A whole week of productivity was slowed down with PPTX and 2007 PowerPoint presentation support. We need to launch our app this week! Please, please…when can this 2007 slide thumbnail rendering be fixed?

Roj Prasad, President
Web Epoch Interactive Inc.

Hi Roj,

Thanks for showing interest in Aspose.Slides.

We are extremely sorry for the delay you are having. We actually introduced PPTX slide rendering in the current release owing to many customers requests. Right now, it has been made publically available in order to collect customer reports, issues and new feature requests. In the next releases, issues will be fixed and new rendering features will be implemented step by step.

It would be really helpful for us, if you could please share any issue example with us, so that we can reproduce and test that issue. This will help us to improve further and make our estimations right.

Once again, we are sorry for the inconvenience.


When is the next release for Aspose.slides .Net being released?

Is there a work around we can do to generate thumbnails that look 1/2 way decent?

I started this project specifically for 2007 PPTX support that Aspose claimed. Now what do I tell the client - they have new slides decks created in 2007 pptx to distribute to 1000s of users and they have been waiting patiently for 30 days. Aspose lack of PPTX support already cost me an extra week.

I am a "dead meat" If I don't deliver a solution this week. Maybe I can streatch the delay until next week BUT I must deliver something functional to client after developing for 6 weeks with 4 programmers.

Can you please please please Help us!



Sounds like you are in dire straits. Support for PPTX is less-important for my project (we’ll manage for now - I think/hope) but if I were under the gun, I would start looking at other options. For example, I might experiment and see if I could perform a SaveAs to PPT from PPTX (using the aspose.slides library). Then open the PPT and use the GetThumbnail() from the PPT Slide objects. The PPT version works very well and as long as the SaveAs “does the right things”, I think it would work in most cases, barring any new 2007 feature which can’t be downwardly compatible.

No doubt, this is clunky and would require a bit more processing (hopefully your presentations are not too big), however, you may be able to do this transparently (without having to have the user saveas 2003 ppt from 2007) until fix is available. This falls into the “purposeful hack” category. I am actually having a meeting about this broken feature tomorrow, depending on management/user’s reaction, I may have to resort to trying this. If I do go down this road, I will share my findings.

Hope this helps and good luck


Dear Don, thanks for sharing the workaround.

Hello Roj,

We can understand the criticality of the issue and we truly believe that you are facing an inconvenience due to this problem. But I am very sorry to inform you that we don’t have any definite dates regarding the resolution of this problem. I am not sure if the workaround shared by Don can be fruitful for you or not, but you can try using this approach for the time being.

Please accept our modest apologies.

Please let me know how this works for you.


Thanks Dan but they can do that with their existing system too.

I revamped my app to meet client's powerpoint 2007 need specifically for a new slide deck done in 2007 powerpoint. Then rest of accounts, within 6 month they work adop my system as it is 5x superior. The client knows this too. I decided to upgrade and add 2007 support for slides due to Aspose website. I am a "double dead meat roadkill" as I have borrowed money against SEP IRA to fund this project hoping to close sale and put money back in retirement account. With our 2007 powerpoint support I will surely lose major this account opportunity.

Beyond thumbnail the re-sizable "slide preview" in the Admin module also looks bad as the thumbnail. Does this mean that the downloaded slide will be bad too? I can't test my download at the moment, hopefully later today.

However if the Aspose process 2007 slides are NOT 100% rendered correctly we are going have have BIG issues with Aspose. I won't be able to sell my online service to anyone.

Does anyone know any other solution? I thought this was an advanced forum for great problem solvers. Please solve this problem, provide a temporary work-around for me and I will create my best culinary dishes for you!

It's Dan - not Don - Musdassir.

You threw me off as I tried to look for a message "Don" - no where to be found.

So Mudassir - Once again I ask.

WHEN DOES YOUR NEXT RELEASE OF Aspose.Slide is scheduled to be realeased? And will this version of Aspose.slides correct the issues we are facing?

How much coding does it take to add this functionality?

Are there any hack or third party solution I can add to my application?


Dear Dan,

Please accept my apologies. I am extremely sorry for mispronunciation.

Dear Roj,

I am once again contacting the development team about the ETA for our new release. We understand your problem, but we are also working hard to solve the issue. Please accept our apologies.

Thanks and Regards,


No probs on calling me Don. I’m actually going to try my own suggestion, I gave Roj. If it works, I’ll publish it.



I spent a bit of time on this, came to realization that the Save function for PresentationEx does not support saving to PPT - even though there is a SaveFormat.Ppt (at least in library I have, 12/29/2009 build)

Aspose.Slides.PptException: This export format is not implemented for PPT yet.

I then tried one approach that looked promising and that is using the save with SaveFormat.Tiff which generates a multi-image tiff. Unfortunately, tiff rendering wasn’t reliable either.

I may end up using COM component to save as ppt as a temporary solution.


Hello Roj,

We are sorry for the inconvenience.

I have discussed the matter with development team. We need your cooperation in terms of providence of code snippet and problematic presentation. Please, share this information with us because this is the only way we can test and verify your problem. After reproducing your issue, we will be in position to update you about how long it may take to resolve the issue. We are aware of your problem and really want to help you out.

Once again, we are sorry for the inconvenience.


An issue with issue id 14157 was created when my leader developer posted this on 2/1/10

We are using the following code for creating Slide Thumbnail.

SlidesEx _slideEx = objPresex.Slides[0];
System.Drawing.Image imgThumbnail = _slideext.GetThumbnail(1f,1f);
imgThumbnail.Save( @"d:\imag\1.jpg);
imgPreview = _slideext.GetThumbnail(1f, 1f);
imgPreview.Save( @"d:\imag\1.png);

1 When we upload our presentation as PPTX with Themes, textures and gradient colors - The rendering of thumbnails and slides are very bad. It looks as if it is being rendered with 64 or 16 colors or even less. THE TEXT IS EXTREMELY BAD.

2) If the background color and slide color is "flat color" from a 64 color palate it renders fine.

3) Very cool and impressive - I added a photograph AS A BACKGROUND on the slides. The thumbnail render perfectly as photo quality. However

A) On the same thumbnail & slide - a "screen shot" text that is heavy looks BAD on top of the same slide with photograph. photograph look perfect.

B) On another thumbnail & slide - a "screen shot" that is graphic heavy looks better but still breaking up while photograph background looks perfect.

Please tweak you code more to solve our issue(s).

This is the code you provide that only created thumbnail.

//Reading the PPTX file

PresentationEx pres = new PresentationEx("D:\\ppt\\Test.pptx");

//Accessing first slide of presentation

SlideEx slide = pres.Slides[0];

//Obtaining thumbnail of the slide

System.Drawing.Image imgThumbnail = slide.GetThumbnail(1f,1f);

//Saving the thumbnail to Jpeg


System.Drawing.Image imgPreview = slide.GetThumbnail(1f, 1f);

//Saving the thumbnail to png



Hi Roj,

Thanks for your interest in Aspose.Slides.

You have provided reference to Issue ID: 14157, created by one of your lead developer. This ID refers to the problem of slide notes addition/copying in PPTX.

I have analyzed the code snippet that you are using and your observations on data. But, I still need to reproduce and verify the things on my end, so please share the presentation data for which you have raised observations.

Thanks and Regards,


Below code we are using :

PresentationEx objPresex = new PresentationEx(strFilePath);
SlidesEx _slideEx = objPresex.Slides[0];
System.Drawing.Image imgThumbnail;
System.Drawing.Image imgPreview;
imgThumbnail = _slideext.GetThumbnail(1f,1f);
imgThumbnail.Save( “E:\ClickPoint\ClickPoint\1.jpg”);
imgPreview = _slideext.GetThumbnail(1f, 1f);

Above code is used for creating thumbnail of aspose slide in png and jpg format . Aspose have default method _slideext.GetThumbnail(1f,1f) used for thumnail . In method no functionality here about how to get quality (bad, best,good).
this method is already there in aspose library that we are using in our project

How to Send you the powerpoint PPTX file and screen shots you you can see what we are seeing. Please advise.

Hi Roj,

I have seen the zip folder and found Jpeg images highlighting the issues. But I am afraid; I am unable to find the source presentation (PPTX) file. Can you please double check the things on your end.

Thanks and Regards,


I have attached the pptx presentation you requested.

I do not see my previous posting.