Inkscape

Changed appearance in roundtrip-edited PDF (incorrect export of masked element inside a transformed group; alpha loss inside clipped groups)

Bug #1457791 reported by hejkki on 2015-05-22

This bug affects 1 person

Affects		Status	Importance	Assigned to	Milestone
	Inkscape	Confirmed	Medium	Unassigned

Bug Description

When i open a specific pdf file, it opens ok.
But when i save it as pdf or svg, the output is totally different from the input file even if i didn't edit anything, i just saved / exported it.

Attached file is an example pdf. Open it in inkscape, save it with another name and open it with adobe reader or other pdf reader.

System info:
“The latest on ubuntu and the development release and windows / linux both.”

--
(Ubuntu version was not shared, nor which Windows installer was tested (32bit or 64bit) --> poppler and cairo versions used by the reporter's Inkscape builds are not known)

See original description

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Revision history for this message

hejkki (heikki-kniivila) wrote on 2015-05-22:

an example input file Edit (295.6 KiB, application/pdf)

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su_v (suv-lp) wrote on 2015-05-22:

Please add information about OS/platform and Inkscape version to the bug description, thank you.

Changed in inkscape:
status:	New → Incomplete

Revision history for this message

hejkki (heikki-kniivila) wrote on 2015-05-22:

i didn't put version information since it affects all versions available.

The latest ion ubuntu and the development release and windows / linux both.
Try the demo file.

Revision history for this message

Alvin Penner (apenner) wrote on 2015-05-22:

Kermatäytekaramelli 72x44mm.svg Edit (748.1 KiB, image/svg+xml)

not reproduced on the input side, using Windows 7 and Inkscape 0.91 r13725 (Jan 30 2015)

attached is the svg obtained on input.

Revision history for this message

Alvin Penner (apenner) wrote on 2015-05-22:

Kermatäytekaramelli 72x44mm_ink.pdf Edit (486.0 KiB, application/pdf)

there is a color change in a background when re-saving this as pdf, see attached file

is this what you were referring to?

su_v (suv-lp) on 2015-05-22

tags:

added: exporting masking pdf

Revision history for this message

hejkki (heikki-kniivila) wrote on 2015-05-22:

yes, the color change.

su_v (suv-lp) on 2015-05-22

description:	updated
Changed in inkscape:
status:	Incomplete → New

Alvin Penner (apenner) on 2015-05-22

Changed in inkscape:
status:	New → Confirmed

Revision history for this message

su_v (suv-lp) wrote on 2015-05-23:

AFAICT the SVG structure generated by the PDF import triggers at least two known issues if resaved as PDF:

1) Bug #427540 - the mask applied to the (scaled) bitmap image inside a group with a preserved transform is incorrectly exported (displaced, or wrong scale): ungrouping the immediate parent group of the masked bitmap image (the group has a matrix() transformation) produces expected appearance in exported PDF (independent of whether the clip-path is released and deleted or not).
2) Bug #1258265 - with cairo >= 1.12.4 the transparency of the masked bitmap image is lost altogether due to being inside a clipped group (cairo bug). Releasing the clip on the wrapping group (doesn't change appearance since nothing is actually clipped off), and ungrouping the parent group of the bitmap image produces expected appearance in exported PDF, even with cairo >= 1.12.4.

Changed in inkscape:
importance:	Undecided → Medium

su_v (suv-lp) on 2015-05-23

summary:

- Generates bad output when opening a pdf
+ Generates bad pdf output when opening a pdf

su_v (suv-lp) on 2015-05-23

summary:

- Generates bad pdf output when opening a pdf
+ Changed appearance in roundtrip-edited PDF (incorrect export of masked
+ element inside a transformed group; alpha loss inside clipped groups)