Bugs item #896, was opened at 2007-12-29 21:00 Status: Closed Priority: 3 Submitted By: Jim Diamond (zsd) Assigned to: Martin Schröder (oneiros) Summary: including an image (pdf or png) with transparency messes up other colours on that page Category: Image inclusion Group: v1.50.0-alpha Resolution: Fixed Initial Comment: Download http://www.libpng.org/pub/png/img_png/stefan_255_rgba.png (which has a transparent background) and run it through png2pdf as follows: png2pdf -i stefan_255_rgba.png stefan_255_rgba-i.pdf png2pdf -a stefan_255_rgba.png stefan_255_rgba-a.pdf png2pdf stefan_255_rgba.png stefan_255_rgba-neither.pdf Then run the following through pdflatex (pdfTeXk, Version 3.141592-1.40.3 (Web2C 7.5.6)) \documentclass{beamer} \mode<presentation> { \usetheme{Madrid} \setbeamercovered{transparent} } \usepackage{ifpdf} \usepackage{graphicx} \usepackage{color} \ifpdf \hypersetup{% pdfpagemode=FullScreen, pdfpagetransition={Wipe /Di 0 /D 0.5} } \fi \title[Beamer and png2pdf]{Using png2pdf with the beamer class} \author[Krause]{D.~Krause} \subject{png2pdf} \begin{document} \beamertemplateshadingbackground{yellow!50}{magenta!50} \begin{frame} \frametitle{NO Image over background} This is some text \end{frame} \begin{frame} \frametitle{Original stefan... png image over background} \includegraphics{stefan_255_rgba.png}% \end{frame} \begin{frame} \frametitle{png2pdf -a stefan... image over background} \includegraphics{stefan_255_rgba-a.pdf}% \end{frame} \begin{frame} \frametitle{png2pdf -i stefan... image over background} \includegraphics{stefan_255_rgba-i.pdf}% \end{frame} \begin{frame} \frametitle{png2pdf stefan... over background} \includegraphics{stefan_255_rgba-neither.pdf}% \end{frame} \end{document} Now look at the resulting PDF (attached) with Acroread 7.0.9 or 8.1.1 on Linux. On the page which includes the PNG and also on the page which includes the png2pdf -a version, the other colours on the page are messed up somewhat. This also happens on Acroread 8.? running on Windoze xp under vmware, although it seems a bit less noticeable. There is no apparent problem when looking at the file with xpdf or kpdf (Slackware 12.0 Linux). It's not clear to me whether this is an acroread bug or a pdftex bug, but Martin Schröder suggested I open a bug here. Cheers. Jim ---------------------------------------------------------------------- Comment By: Yannick B (bers) Date: 2010-09-04 09:38 Message: Hi, I just ran this example through pdfTex 1.40.11 (MiKTeX 2.9 beta). What I found out is that this issue is fixed for the png, but not for the transparent pdf file (png2pdf -a). File: beamer_1.40.11.pdf. You see that the colors on slides 1 and 2 are different. This might need another fix. (I assume it worked once, but was accidently removed in a later revision, perhaps due to what I'll point out now.) I also noted that the bug fix for the png has a very ugly side-effect, which I illustrate by two snapshots (snapshot_original.png, snapshot_1.40.11.png). You clearly see that the white font is more "bold" in the new version; also, you note a white frame around the image, and that the symbols in the lower right corner show some artifacts - especially the circle-arrows. This is a rendering issue in Acrobat on some systems, which has been encountered and described by others already. A minimal example of this effect can for example be found here: http://forums.adobe.com/message/3108003 A reason for this might be the missing inclusion of "blending space" information, as pointed out in the reply to above's post. This same issue has also been described for pdf file inclusion, see here: http://sarovar.org/tracker/?func=detail&atid=493&aid=4294&group_id=106 In that case, it is based on incomplete page group information of the included pdf. However, as also pointed out in that discussion, a new page group is synthesized for png files, so there needs to be something wrong with that. It is really an annoying bug, as pages with an without transparent pngs in them may look different to your reader. I do not have enough knowledge to assign the different effects to their respective root causes, but I do believe that this bug entry here might be a good starting point. Last question: How do I attach files? I will as soon as I have found out. ---------------------------------------------------------------------- Comment By: Martin Schröder (oneiros) Date: 2008-01-14 17:25 Message: Logged In: YES user_id=421 A fix for this will be included in the next release (1.40.6/1.50.0). ---------------------------------------------------------------------- Comment By: Martin Schröder (oneiros) Date: 2007-12-31 16:07 Message: Logged In: YES user_id=421 Our contact at adobe confirms that pages with transparent objects on them (like pngs) must have a /Group entry in the /Page object. I'll fix that next year. ---------------------------------------------------------------------- Comment By: Martin Schröder (oneiros) Date: 2007-12-29 22:05 Message: Logged In: YES user_id=421 This is not related to #764, as there are no page Groups. It also happens only with the png or rgba-a. I'll ask our contact at Adobe. ---------------------------------------------------------------------- Comment By: Jim Diamond (zsd) Date: 2007-12-29 22:03 Message: Logged In: YES user_id=4814 I just d/l'ed and compiled pdftex Version 3.141592-1.40.5 (Web2C 7.5.6) The pdf files (1.40.3 and 1.40.5 versions) are slightly different (when compared as text) but when viewed with acroread 7.0.9 they look identical (as far as my eyes can tell). ---------------------------------------------------------------------- Comment By: Jim Diamond (zsd) Date: 2007-12-29 21:15 Message: Logged In: YES user_id=4814 Done ---------------------------------------------------------------------- Comment By: Martin Schröder (oneiros) Date: 2007-12-29 21:08 Message: Logged In: YES user_id=421 Please attach the pdfs from png2pdf. ---------------------------------------------------------------------- You can respond by visiting: http://sarovar.org/tracker/?func=detail&atid=493&aid=896&group_id=106