QTR-Quadtone RIP

Hi Kamil,

I've had some more time to look into this.  From what I can tell its a
memory allocation failure for
images greater than 2 Gigabytes (2**31 -1).  Unfortunately your 1-bit
tiff file is converted to a regular
8-bit grayscale when read with the standard OSX routines.  (I'm
guessing that way most of system code
can handle your 1-bit data).  So if your height x width > 2147483647
there's a memory failure
and the "all black" output is essentially a zero buffer.

Interestingly the OSX program Preview handles the large file because
it apparently chops up the
file into lots of smaller pieces.  This obviously has some advantages
(like here) but seems much
slower for some operations like re-sizing.  I have seen problems in
the past with the seams of chopped
images not lining up exactly correctly -- not sure if this would
happen here.  So you might try
Preview for printing and see if that gives you what you want.

However backing up to your original issue:
I looked at the screen capture images you've posted.  You seem to be
trying to print resolutions that
are way over what's actually possible.  QTR prints 720x720 ppi images
-- i.e. everything is scaled to 720.
You have 100/mm resolution which is 2540 dpi.  All this extra dpi is
being thrown away.  If you
get your images down to 720ppi you'll be able to deal with very large prints.

Roy


On Sun, Mar 3, 2013 at 6:11 AM, kamiltresnak <kamiltresnak@yahoo.com> wrote:
>
>
> Hi,
>
> many thanks to Roy for the private reply.
> I am attached better images from the real printing tests.
> Meanwhile, i tested our files with some others applications, and it is interresting, that Graphic Converter, while opening file, is reporting error that dimesnion of image is larger than 64000 pixels.
>
> Seems to me that problem is somewhere in variable declaration (unsigned integer?) in printing application QTR Print tool or OSX printing routines, which QTR Print Tool uses.
>
> As you can see on new images, when one of the dimensions of the image exceed some at the moment undiscovered size under 65000 pix, print fail. I am pretty sure that QTR will be capable print files with bigger data size, as we test some grayscale (8bit) files with large dimensions.
>
> Is there any possible fix in QTR tool? Or this is limitation of OSX?
> maybe some others ways? ImageMagick? Or some simple routine, which can "slice" large images to smaller parts and print this file separately?
>
> Driver (QTR RIP) is working like a charm, so basically, we need any tool which can send print data to QTR.
>
> Thank you for any idea,
>
> Best regards
>
> Kamil Tresnak
> (sorry for possible grammar and languaqe errors)
>
>
>
> --- In QuadtoneRIP@yahoogroups.com, "kamiltresnak" <kamiltresnak@...> wrote:
>>
>> Dear all,
>>
>> we have problem (i suppose) with Print Tool on a Mac.
>> We print 1-bit tiff files through QRT to the Epson 9900, and print is OK if we print files with dimensions cca 30000x47000 pixels, even when we place to GUI several copies of that file and print them together. But when printed file with height more than cca 50000 pixels, printer prints just solid black area, no matter image data. We do not know where limit exactly is, as testing is very time consuming. Printing the same file cropped to approx 1/2 is OK, but what is interesting, original big file, which we move cca 1/2 outside from paper format is printed not OK (same black box again). We test another workflow, and original not cropped big file, printed from Mac application Preview to QTR Rip is OK.
>> Considering all of this, IMHO this is some kind of problem in QRT Print tool, which -probably- is working with some pixel size limit (probably not in terms of data size or resolution, but linear pixel limit).
>> I understand, that 60000 pixels is not low value, but note that image file size is consíderably lower, cca 350MB.
>> Any ideas, workarounds, experiences?
>>
>> Attached in album (see link bellow) are images (original screenshot was "stolen" from www.piezography.com, sorry, but i have not access to QTR Print tool at this time) with very basic and rough explanation fo problem (not real screenshots).
>>
>> Thank you very much for your time and support.
>> Hope you understand, as English is not my native language.
>>
>> All the best
>> Kamil Tresnak
>>
>>
>>
>> http://groups.yahoo.com/group/QuadtoneRIP/photos/album/886111318/pic/1239631189/view
>>
>
>
>
>
> ------------------------------------
>
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>
>
>



-- 
Roy Harrington
roy@...
www.harrington.com