Impressive (and various dependencies) installed just fine, but when I tried to open one of my slide shows, I got the following error:
So I tried opening a random PDF I had lying around my laptop's desktop screen, and lo and behold it opened! After banging on Google and finding mostly rather antiquated posts, the most plausible explanation I could find was something about graphics being produced in a "recent" (several years ago) version of PDF and the current (back then) version of the PDFtk toolkit (pdftk) having a bug, with the suggested fix being to revert to an older version of pdftk. I looked in the Synaptic package manager to see what version I had, and it turned out the answer was none!Warning: The input file `<path to my file>' could not be analyzed. The presentation doesn't have any pages, quitting.
I installed pdftk (and necessary dependencies) from the Canonical repositories, and that fixed the problem. Impressive now worked just fine with my presentation. This leaves me with a few observations:
- Neither pdftk nor any of the dependencies that installed with it must be absolute dependencies of Impressive, since Impressive was able to display the second file I tried without having pdftk etc. installed.
- The pdftk bug mentioned in the old posts has, I'm pretty sure, long since been fixed ... and, in any case, that wasn't the problem, since I did not have any version of pdftk, buggy or not, installed.
- Either pdftk or one of its dependencies, while not strictly required to run Impressive, must be required to correctly parse something (all graphics? some graphics? something to do with the use of overlays?) in my presentation.