I just found about podofocolor on http://domseichter.blogspot.dk/2011/01/modifying-and-analyzing-colors-in-pdf.html - and I got really interested in "Analyzing colors - Find out, which colorspaces or colors are used in a PDF". I couldn't find an example of how to do that on that page, and I assumed the only way to do is through Lua.
Unfortunately, while there are some PPA builds for Ubuntu ( see http://sdaaubckp.svn.sf.net/viewvc/sdaaubckp/offext-call-scripts/podofo.sh ), those do not have Lua built-in, so I rebuilt podofo and utils on Lucid, and posted the executables here - since they are statically linked, they may be useful to others as well:
I have also recorded the steps to building those executables in http://sdaaubckp.svn.sf.net/viewvc/sdaaubckp/source-build-scripts/get-podofo-src.sh
The above directory also contains a modification of the example.lua script:
... which can be used to simply print out any color encountered in a PDF, by using this command line:
$ ./libpodofo-utils-lucid/podofocolor lua example-colorlist.lua /path/to/mytest.pdf /dev/null
<</ID[<XXXX><XXXX>]/Info 2 0 R/Root 1 0 R/Size 16>>
Processing page 1...
-> Lua is parsing page: 1
Reading object 6 0 R with type: Number
set_non_stroking_color_cmyk: 0.233887 1 1 0.218994
Note that it is important to add `/dev/null` as output file - otherwise, both the color report _and the pdf in its entirety_ will be dumped to the terminal - making the report about colors impossible to read.
I would have appreciated a lot a similar guide/explanation on the blogspot webpage (or in a help/readme); and I'd be very happy if some of this here can contribute towards more detailed examples in then documentation.
Many thanks for the great software,