Large bitmaps inside SVGs are not displayed

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Large bitmaps inside SVGs are not displayed

Postby vocx » Sat Dec 14, 2019 11:13 pm

I tried uploading a large SVG file that has an embedded bitmap image (PNG).

I did it this way because the PNG image shows static information, and with Inkscape I add annotations, text, arrows, squares and similar vector graphics.

The image is this one ... isions.svg

This should work fine, but the wiki doesn't display it. You can however, download it and open it fine in your computer.

The wiki shows this error: "Invalid SVG file: Expected <svg> tag, got in NS"

I investigated the problem and it seems the MediaWiki software has a limit on the size of the SVG files that it will show. Since an SVG is an XML file that has a shape description language, its contents are normally just text, so the software expects to parse a small file (maybe less than 50 KB). However, when it includes the bitmap image, there is a lot of binary information embedded in the file, and the wiki fails parsing the file. This file in particular is around 350 KB, which isn't very big for a bitmap image, but it is for an SVG.

It seems the solution is to set the variable "wgSVGMetadataCutoff" to a larger value in the configuration files of the wiki, which only administrators can do.

* Invalid SVG files (Using Inkscape)
* Thumbnails of certain SVG files fail to render

Meanwhile to solve this issue, I convert the entire SVG file to a static PNG, and this is displayed correctly. ... isions.png
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