I have Acrobat 8 Professional 8.1.2 as part of the CS3 Design Premium Suite on a Mac Pro (running Leopard 10.5.4). I have a Fujitsu S510M document scanner, and recently used it to scan an enormous pile of old personal documents. Most were black and white documents (e.g. xeroxes), and with the settings I chose for these documents, the scanner's software produced what look like bitmap or 1-bit black and white PDF files. So far so good. If I attempt to use Acrobat's Touchup Object tool to clean up scanned pages in these PDFs, I get a message in Photoshop CS3 saying: "Could not complete your request because a color was specified using an unsupported color space". A peek at one of these PDFs thru Preflight reveals the following about one of these troublesome objects:
"Bits per color component: 1
Treated as a mask: False
Perform interpolation: False
Rendering intent: Perceptual
ZIP/Flate compression: FlateDecode
Number of color components: 1
Alternate color space
DeviceGray color space
ICC profile data
Profile version number: "2.2.0"
Color Management Module (CMM) type: "appl"
Profile/Device class signature: "mntr"
Color space of data: "GRAY"...
Profile description: "Generic Gray Profile"
Is it the DeviceGray color space that is making these objects uneditable?
Is there a color conversion I do with Convert Color or some other trick I can
do to make these objects more Photoshop-friendly?
I just tried that in Acrobat 8 Pro here at work--no change.
I also tried converting to sRGB, to Grayscale, etc. within
Preflight. No luck. I get Error messages saying that
"Trimbox or Artbox missing" and the following explanation
at the bottom of the Preflight window" "Either ArtBox or
TrimBox should be defined for pages in a PDF file that is
used in prepress. For PDF/X files this is mandatory."
Peculiarly, if I change the Touchup/Image Editor preference
to Graphic Converter, I can successfully open these bitmap
images for editing without a problem, which is a workaround.
Those errors were not related to your particular file - did it not open
in Photoshop? Make sure you're fully patched to the latest version of
BOTH Acrobat and Photoshop - if problems still exist then post on a
website for us to take a look ...
I cannot tell you why you cannot get to it. I couldn't in PS directly
nor with the Acrobat touchup tool in Acrobat 9. The best way to get to
these files is to export to tiff, where they show up as B&W. Then you
can touchup in PS to your hearts content.
It's puzzling to me, especially because these are generic PDF files generated by the Fujitsu S510M's scanner's software, a thoroughly Mac- and Leopard- compatible product which even comes bundled with a full license for Acrobat Pro 8 (which I didn't need, BTW, as I already had the CS3 Design Premium Suite with Acrobat 8 in it). Also, the fact that Graphic Converter can handle these scanned pages as an image editor points to something anomalous--why would a non-Adobe product be able to edit a bitmap image without a problem, whereas a supremely capable and powerful application like Adobe's Photoshop can't handle something embedded in a file that is an Adobe file-format. These files can be even be rezzed down thru Acrobat's PDF Optimizer...
The image is ICCBased Grey and indeed, Photoshop seems to have an issue
opening the file through touch-up. If I use a third-party plugin
(Pitstop) then I can convert back to DeviceGrey without any issues ...
Jon, thanks for taking the time to confirm this problem. I don't have Pitstop nor do I really have any need for it in my home studio, so I guess I'll be using GraphicConverter as my cheap and easy workaround. Did you use Acrobat Pro 9 or 8? I was wondering if Acrobat 9 can handle it, but I won't be upgrading to Acrobat 9 until all of CS4 comes out.
Thanks, Steve. I'm still hoping there is some not-so-obvious setting within Acrobat 8 that can do it. So far this has seemed like needing to cut a simple piece of paper that not even my super-sharp scissors can't cut.
Sorry - was on the way out of the door this morning when I typed the
response. I could not get Acrobat to convert the colour via decalibrate,
preflight, direct conversion of any other means inside of Acrobat ... hmmm
I tried the file and also was not able to open it. It appears that the PDF has the image saved with some ZIP compression, and I'm gonna bet that there might be an error in the zip encoding. Exporting to Tiff from Acrobat worked OK for me. But oddly, using Acro 8 Pro default Tiff export settings, Photoshop says that Pixel Aspect Ratio is turned on, and the image is compressed horizontally. The image's pixel aspect ratio is .5, so maybe the compression of the image is non-standard or broken. If I turn OFF all image compression when exporting to Tiff, it was OK when opening in PS.
I'd guess perhaps Graphic Converter's algorithm is more lenient to opening problem files than PS is. I've also seen PS report color space errors when files had non-matching file extensions (ie a JPEG saved with ".tif" or vice versa).
I think I'm going to contact Fujitsu's tech support to inquire about this. Even though the mighty Photoshop is inexplicably choking on simple images that behave well within the Acrobat environment, it's still Fujitsu's software that is creating these problematic PDFs.
I truly appreciate everyone's input. For all I knew, I was being blind to something easily fixable, but in this case it seems like there is something truly buggy going on.