bug#14580: 24.3; docview-mode doesn't work for multi-page pdf in 24.3

[Neal Becker]

When using gs to convert, I do get 3 _different_ png files.

Using docview, it's really weird.  I hit 'g', and answer 'yes'.  As I page through, it says pages 1/3 ... 3/3, but it displays _the same image for all 3 pages!!_.  I tried repeatedly killing buffer, visiting, hitting 'g' to reload - nothing I tried seems to fix it. 

On Tue, Jun 11, 2013 at 2:33 AM, Tassilo Horn <tsdh@gnu.org> wrote:

Neal Becker <ndbecker2@gmail.com> writes:

Hi Neal,

> Also, these are not some special files from XeTeX.  I'm using
> matplotlib,

I've tried opening your sample PDF about a dozen times using emacs 24.3
as well as the current emacs trunk, each version both with -Q and with
my customizations.  In all cases, the PDF had 3 pages...

> and it seems to happen something like 50% of the time.

One thing that might explain parts of your problem: when you open the
file initially and then something fails and only the first page is
converted, then any subsequent opening of the file will only access the
single cached image without checking if the PDF has actually more pages
than there are images already.  To force a reconversion, you can hit `g'
in the doc-view buffer.

But still, if ghostscript or mupdf error when converting a document, you
should at least get some message like "ghostscript terminated with exit
code XX"...

Not sure, but maybe it's a problem with your ghostscript or mupdf
version.  What's the value of `doc-view-pdf->png-converter-function'?
If it is `doc-view-pdf->png-converter-mupdf', then try

  $ mudraw -o doc%d.png doc.pdf

on the command line.

If it is `doc-view-pdf->png-converter-ghostscript', then try

  $ gs -dSAFER -dNOPAUSE -sDEVICE=png16m -dTextAlphaBits=4 \
       -dBATCH -dGraphicsAlphaBits=4 -dQUIET -sOutputFile=doc%d.png \
       doc.pdf

Does that produce one image per page in the PDF, i.e., 3 images for your
sample file?

Bye,
Tassilo