Compatibility 0.91 with older versions

Please add information about OS/platform to the bug description.

If on Windows, please provide also information about which installer was used (32bit, 64bit).

<off-topic opinion>Please keep in mind that Inkscape is not a PDF Editor - Inkscape's native file format is SVG, a vector file format with a different feature set than PDF. Opening/saving as PDF is always a conversion between file formats (PDF -> SVG, SVG -> PDF) which is bound to be lossy, due to the different nature of the file formats (and due to the two different external graphic libraries used for import (poppler) and export (cairo). Repeated round-trip editing of PDF files in Inkscape will at some point very likely produce visual differences.</off-topic opinion>

The background of the SVG file uses sliced bitmap images which due to a bug in older Inkscape versions lack the attribute 'preserveAspectRatio' (in the SVG source). This bug in older Inkscape versions (non-conformance to the SVG 1.1 specification) was fixed in Inkscape 0.91, with the side-effect that bitmap images in SVG files created with older Inkscape versions which are non-uniformaly scaled, and don't have the correct 'preserveAspectRatio' attribute set (value: "none"), render differently in 0.91.

Reports which tracked the original problem in older versions:
- Bug #461467 “Image scale saved incorrectly (preserveAspectRatio)”
- Bug #616717 “Resized bitmap images are rendered differently by Firefox or Batik ('preserveAspectRatio' attribute not set)”

Ideally, Inkscape 0.91 should offer an internal feature to "fix" such files, as described in this report:
- Bug #1357808 “trunk: add extension to fix rendering of non-uniformly scaled bitmap images”
  https://bugs.launchpad.net/inkscape/+bug/1357808

Bug #1357808 includes an extension which you can apply (in 0.91) to files like the one attached here, to "fix" the mistake of earlier Inkscape versions, and have all images rendered with the applied scaling without restrictions (preserved ratio).

On 2015-02-11 09:50 (+0100), Tobias Schunn wrote:
> By zooming in into the drawing there appear white splashes to the
> places, where the mouse-pointer is.

Not sure - this could be a renderer issue, and depend on which cairo version is used by Inkscape on your system ( information about OS/platform pending).

Attaching test case saved after running the extension from bug #1357808.

The same issue was also reported in bug #1417277 - imvho both 1417277 and this one (1420679) could be tracked as duplicates of 1357808 (Inkscape 0.91 is correct, but needs options to adjust "incorrect" files created with older inkscape versions).

Another difference wrt to linked or embedded bitmap images between 0.48 and 0.91 is their "smoothness", as tracked in
- Bug #1418038 “Interpolation while viewing in-file bitmap image”
The report has another extension attached which can be used to adjust the rendering mode of bitmap images in various scopes (convenient for files with many bitmap images since 0.91 only has a GUI option to change the rendering mode for a single selected bitmap image).

Thank You for the fast answers. I've tested it with Windows 7 and Windows 8.1. It's the installer "inkscape-0.91-x64"
The extension works - thanks! Unfortunately thin lines from the bitmap weren't rendered.

On 2015-02-11 21:26 (+0100), T. Schunn wrote:
> Unfortunately thin lines from the bitmap weren't rendered.

Did you try to chnage the rendering mode to 'blocky' (optimizeSpeed)? (see earlier comment wrt bug #1418038)

I am also having the same problem. If you use the example file the initial posting had...Although the extension preserveAspectRatio does work in restoring the imported pdf image...now file editing with .91 i.e. just adding text becomes painfully slow. I can type a line of text and watch is slowly appear in slow motion on my screen. No such problem if using .48 with the same file.

I am using .paf versions of .48 and .91
windows 7 pro x64 intel I-7 8gb ram

On 2015-02-16 03:41 (+0100), mrw2day wrote:> I am also having the same problem. If you use the example file the
> initial posting had...Although the extension preserveAspectRatio does
> work in restoring the imported pdf image...now file editing with .91
> i.e. just adding text becomes painfully slow. I can type a line of text
> and watch is slowly appear in slow motion on my screen. No such problem
> if using .48 with the same file.
>
> I am using .paf versions of .48 and .91
> windows 7 pro x64 intel I-7 8gb ram

@mrw2day - performance issues as described are unrelated to the issue tracked here (Inkscape's improved SVG compliance wrt rendering of scaled bitmap images affects files generated with older Inkscape versions) and should be tracked separately. Please check for existing performance-related reports before filing a new one.

Note that on many systems (depending on installed graphics card) the new 64bit build of Inskcape for Windows will be affected by bug #1351597.