On Fri, Dec 31, 2010 at 2:50 AM, Robert Krawitz <rlk at alum.mit.edu> wrote: > On Fri, 31 Dec 2010 02:41:10 +0900, Gernot Hassenpflug wrote: >> On Fri, Dec 31, 2010 at 2:19 AM, Gerard Klaver <gerard.klaver at xs4all.nl> >> wrote: >>> On Fri, 2010-12-31 at 01:29 +0900, Gernot Hassenpflug wrote: >>>> Dear all, >>>> I have been involved in trying to support the Canoscan 9000F, and the >>>> testing community has grown to about 15 individuals. A few of them >>>> have programming knowledge and tonight one individual send in >>>> corrected code to handle the final hurdle: correctly aligning the >>>> sub-images in the 9600dpi TPU mode. So the scanner is now supported >>>> for all modes. >>>> >>>> However, for large images at both 4800dpi and 9600dpi modes, it seems >>>> the max size of the image is limited in some way, so that only a >>>> section of the desired image is delivered. Is this something that can >>>> be set in the individual driver files (like pixma_mp150.c) or in some >>>> of the generic pixma driver .c or .h files (which I do not want to >>>> touch if possible)? I don't see a problem in the linesize or >>>> dimensions, only in the image_size value seen by [pixma] debugging >>>> output. >>>> >>>> Best regards, >>>> Gernot Hassenpflug >>>> >>>> -- >>>> sane-devel mailing list: sane-devel at lists.alioth.debian.org >>>> http://lists.alioth.debian.org/mailman/listinfo/sane-devel >>>> Unsubscribe: Send mail with subject "unsubscribe your_password" >>>> ? ? ? ? ? ? ?to sane-devel-request at lists.alioth.debian.org >>> >>> One possible solution (if not yet done), is to check the declaration of >>> the ?image_size parameter, for a 9600 dpi A4 scan (color) size is about >>> 550 000 000 000 bytes. (long long is needed) >> >> Hi, thank you for that. I see that image_size is currently declared as >> "unsigned". I imagine that changing the declaration will need to be >> checked in all places where the calculations using image_size are >> done, or not? >> >> Currently, from the report I obtain from a test user, a 4800x4800dpi image >> with >> >> dimensions: 32824 px (width) * 47248 px (height) >> >> should have a image_size of 4652605056 bytes (W*H*3 for channel number) >> >> whereas the actual image_size used is 357637760 bytes (approximately >> 341.1 MiB). I am still trying to ascertain whether for some reason the >> wrong calculation for image_size might have been made, but certainly >> the width and height are correctly there. > > 32824 * 47248 * 3 - 357637760 = 4294967296 > > which is exactly 2^32. ?So that suggests exactly the problem described > above.
Ah! I suspected it was that, but forgot I had to take the difference to get this number. Fantastic! Well, that sounds like somewhat of a issue then for the SANE Canon maintainer to comment on. I guess this issue had to come up eventually. Thanks, Gernot Hassenpflug
