Hello Lori, 

I came across an older post (not mine) with the following information that might help. 

The error you're running into could be because you are mssing the <?xml .....?> statement at the top of the SVG file (original thread diagnosis by Steve Piercey).

SVG structure requirements and limitations are in manxpp.pdf - chapter 18, pages 18-22 and 18-23).

This missing header information could be what's preventing XPP recognizing the filetype and resulting in the error you're seeing. 

Thank you, Thomas! We are using classic mode.  Looking at the documentation, it looks like .svg files can only be used in XML mode. Is this correct?

Do you or anyone else know if we have to have extensions inserted on graphics being imported into XPP?

Hello Lori, 

As long as the SVG file has everything XPP needs, the SVG file is rasterized to JPG for use within the DIV.
(tagged color info (such as Pantone numbers) will be lost).

I did run a quick test by removing the file extension from an EPS file - XPP was still able to display the image within the DIV. A post from 2013 supports this & indicates that XPP reads the file header information inside the graphic instead of the file extension.

Lori,

If you are unsuccessful with importing .svg files, it might be because the java run time environment has not been loaded onto your system. 

It is something that gets easily overlooked during the installation process as XPP itself runs OK without it.

Here is the para from the XPP Installation and upgrade guide for Windows that talks about this (chapter 1)

Java
If you use Scalable Vector Graphics (SVG) or compressed SVG (SVGZ) images,
EDGAR/HTML, XPP Compare, publish using the Perl ePub module, or use
XSLT 2 to manipulate data before publishing, you must install Oracle Java 1.8
or later, which you can download from java.oracle.com.

The importing of SVG files has nothing to do whether you are using classic mode or xml mode. That only has an influence on the text files you want to import into the system
So you can happily import SVG files when using XPP in Classic mode.

The SVG file itself is a graphic xml file (hence the confusion). XPP has to convert the SVG file before it can be used. And for this conversion step XPP uses a java based tool. Hence the need to have at the very least a java run time environment loaded on your system...

Maybe you need to talk to your system administrator or the person responsible for installing the XPP software on your system.

Thank you for your response. We will look definitely into this.

Hi, Lori ... In addition to the excellent comments from Tom and Bart, I had the pleasure of needing to do a deep dive into XPP SVG rendering issues many years ago.

The java tool XPP uses for rendering is Apache batik-rasterizer a/k/a Batik SVG Rasterizer. It's important to know that this is somewhat configurable in XPP. This may all be well-documented but I'll just share a couple things. 

In our line of work, most SVG images we work with are not developed as native SVG, but converted from Adobe Illustrator or from CGM-type vector images from CAD applications. We've even seen what were obviously originally TIFF images ingested into CAD systems and converted again to SVG as an output. So they are in effect static raster images wrapped in SVG tags. And often missing important vector information in the wrapper part. That is to say, "SVG/vector in name only." Which introduced a host of quality and rendering issues. Hence, the need to manipulate these in the XPP Batik settings. 

Not to let Adobe Illustrator off the hook. Their SVG output sometimes has issues, too.

In the most extreme cases, we had to preprocess the "SVG/vector in name only" art to add missing information so that XPP would render them in an acceptable quality. Hopefully you won't have to go there, as it will require some research into SVG tagging (it's been 15 years, but I think our specific issues had to do with incomplete or invalid tagging in the root <svg ...> and especially the "viewbox" attribute values.)

The workings of the Batik SVG Rasterizer can be found here: $XYV_EXECS/sys/gr/batik

You can get the native help summary by typing: java -jar $XYV_EXECS/sys/gr/batik/batik-rasterizer.jar

The config file in this folder named "batik-config" can be modified as you discover command line options that may help you. For example, we made this change from the original:

jbaldwin-49> cat batik-config.default
-q .99

jbaldwin-50> cat batik-config
-q .99 -dpi 96

I think you can also add a "java-config" file here if you want to add java command line options, for example if you want to bump up the java heap memory.

-Jay Baldwin (Tweddle Group)

Thank you for this helpful information.

And just to add to everyone else's excellent comments.

As far as I can remember this is the only thing in XPP where filename extensions on images are important (excerpt from latest XPP 9.6 version of Managing XPP manual):

That's very interesting and good information to know. Thank you!