I have a PDF constructed using Imagemagick converting text to png overlaying onto a background and converting to PDF.

It renders perfectly on Linux using DocumentViewer or Adobe viewers showing a little red logo in the header - nice.

If I transfer the file to a Windows 7 the logo is in grey scale when viewed in Adobe Acrobat or any Adobe product.
This happens a number of Windows machines I have tried.

If I use Chrome or Windows 7 PDF viewer the colour renders okay.

I've looked through the Adobe settings and nothing seems to affect the lack of colour.

I tried converting a jpeg image to PDF transferring to Windows and viewing with adobe and the colour is good.

This is weird. does anyone know about such weird things?

microsoft really dislikes opensource

png is fully open

xp HATED the png format ,it is not to surprising that the Adobe reader on 7 is only seeing grayscale


what version of libpng is installed on the win machines ?

i am betting a very random mix of multiple installs 11 through 16

but what is in C:\\WINDOWS\system32

Although a great fan of the png format, the mystery colour loss is with the PDF format.
On linux it renders as colour and also on Windows but not using Adobe.
Unfortunately many people will be viewing the pdf image on Windows using Adobe.

It would be great to be able to find why this is so and thus do business with the devil.

that pdf has a png image in it
and you stated that the JPG version did not turn gray

that pdf has an embedded png image in it

and seeing as SOME windows7 machines see the color and some do not

it is likely a libpng problem

like
you made the pdf using libpng16
but windows7 has libpng 11 or 12

Okay I didn't realise an image format was preserved in the PDF - I assumed it would be converted to some internal native format.

Even so the colour shows on a Windows machine for Chrome, Windows 7 PDFviewer and Firefox which infers that therere is a graphic library in there somewhere that recognises PNG format.

Unfortunately the world at large uses Adobe to view PDFs and Adobe doesn't show the colour.

I am doubtful the problem is because of the version of libpng but I may be wrong.
Please can you explain how I can find what version of libpng is on a Windows machine?