Am 18.02.2012 12:40, schrieb ibu ? radempa ?: >> >> You need to investigate 2 things: >> (1) 1200 x 1200 dpi: >> (a) Does the scaned image contain all expected pixels (w x h)? > > Yes, the image size is correct. > >> (b) Please check the pnm image for mixed columns. It seems that two half >> pictures are bitwise mixed. The result is a streched image with a shadow >> of the 2nd half picture. It's easy to solve this line by line with a >> (new) reorder_pixels function. You can have a look to similar functions >> in the pixma_mp810.c file. > > With the attached patch (just disabling pixel reordering, as for MP220) > everything ist fine, please commit it.
OK > > (To exclude yet another pixel reordering mistake I tried to swap even > and odd pixels ( > > memcpy (linebuf + c * (1 - (i % 2) + (i / 2) * 2), sptr + c * i, c); > > ) and got parity_inverted.pnm while without reordering I got > correct_order.pnm .) > >> (2) 2400 x 1200 dpi: >> Here we should take care that the scanner gets the correct formatted >> scan command. >> Can you sniff the usb protocols on a windows machine and compare it with >> one from a linux machine? Both for 2400 x 1200 dpi. The positions of the >> parameters can be read from the send_scan_param function. You can use >> e.g. wireshark for sniffing. The scan command starts with "d8 20 00 00 >> 00 00 00 00 00 00 00 00 00 00 00 38". > > Luckily I don't have windows, so I tried Canon's scangearmp 1.70-1 > package for debian and found that it also allows only up to 1200 dpi. I > suggest to leave 1200 dpi as maximum resolution. (For completeness I > attach some hexdumps of the respective usb request blocks.) > OK, we leave 1200 x 1200 dpi as maximum resolution. > In the list of working devices on the website I'd suggest to add a > comment for Canon MX360: ADF working partially. > In sane-pixma.man I added MX360 to the list of sometimes hanging scanners and in pixma.desc I added the comment: ADF empty buggy. I just committed everything to git. Many thanks for reporting and debugging this scanner. Cheers, Rolf
