Comment 8 for bug 786117

You might be able to narrow down the problem by running the filters in the chain by hand.

You can find out the job attributes that were sent for the job by examining the /var/spool/cups/c* file like this:

python
import cups, pprint
r=cups.IPPRequest()
r.readIO(file("c00038").read)
pprint.pprint(r.attributes)

First of all, check that they look correct.

If they are fine, run the next filter in the chain. If your print job is the PNG file as-is, and you're using the hpcups driver, the next filter will be "imagetoraster".

You can run it like:

PPD=/etc/cups/ppd/myprinter.ppd \
  /usr/lib/cups/filter/imagetoraster 1 me '' 1 \
    'number-up=1 InputSlot=Auto other-job-attributes...' \
    /var/spool/cups/data/d00038-1 \
    > image.rast

where the relevant attributes you got from examining the c* file go on line 3, and line 4 is the PNG file you sent.

You can then examine the "CUPS Raster" format output using the rasterview package.