On Sat 09 Jan 2021 at 03:53:28 +0000, Dr. Jennifer Nussbaum wrote: > Just to clarify what someone else in the thread asked about, the user > I'm running this under _does_ appear in the scanner group.
For what you wish to achieve, being a member of the scanner group is completely unnecessary. See https://wiki.debian.org/Scanner > On Friday, January 8, 2021, 07:07:40 PM EST, Brian <a...@cityscape.co.uk> > wrote: > On Fri 08 Jan 2021 at 17:28:16 -0500, Jen Nussbaum wrote: > > >> When I run simple-scan, it detects the printer and announces itself > >> ready to go, but when I try to scan anything, I get the message > >> "Failed to scan Unable to connect to scanner". I Googled for anything > >> related to this; there's a bunch of stuff on Ubuntu and Mint forums > >> about purging the "ippusbxd" package, but this isn't on Debian. > > > > ippusbxd is certainly not on Debian but ipp-usb is. See the wiki. > > Yes, and I do have that; the point was just that the solution that > worked onMint (to remove ippusbxd and install ipp-usb) isn't relevant > here. ipp-usb is relevant insofar as it enables the sane-escl and sane-airscan backends to be used for scanning. > >> I then ran simple-scan with the debug flag, and at the moment I try to > >> initiate a scan, I got: > >> > >> [+20.83s] DEBUG: simple-scan.vala:1817: Requesting scan at 150 dpi from > >> device 'escl:http://127.0.0.1:60000' > >> [+20.83s] DEBUG: scanner.vala:1683: Scanner.scan > >> ("escl:http://127.0.0.1:60000", dpi=150, scan_mode=ScanMode.GRAY, depth=2, > >> type=single, paper_width=0, paper_height=0, brightness=0, contrast=0, > >> delay=3000ms) > >> [+20.83s] DEBUG: scanner.vala:828: Processing request > >> [+20.83s] DEBUG: scanner.vala:889: sane_open > >> ("escl:http://127.0.0.1:60000") -> SANE_STATUS_NO_MEM > >> [+20.83s] WARNING: scanner.vala:893: Unable to open device: Out of memory > > > > Nothing about the pixma backend (driver)? > > pixma only appears during the startup: > [+7.62s] DEBUG: scanner.vala:353: Device: name="pixma:04A91913_47A8A4" > vendor="CANON" model="CanoScan LiDE 300" type="multi-function > peripheral" > > > Just to confirm your experience, what happens with scanning with > > > > simple-scan "pixma:04A91913_47A8A4" > > This fires up simple scan, and when I click on "scan" it scans the > document successfully. I would not expect this to hapen when ipp-usb is active, which it is. See https://wiki.debian.org/CUPSDriverlessPrinting > > and > > > > simple-scan "escl:http://127.0.0.1:60000" > > This does _not_ work; the response here is the same as when I run it > normally, i.e. the "Unable to contact scanner" error. sane-escl is designed to work with an active ipp-usb. This may be a bug in the backend. > >> I don't know why I tried this, but I then ran simple-scan as root, > >> and...it worked perfectly. > > > > I do not understand why this should be so. Do both the previous commands > > work as root? > > The "pixma" version worked as root, as it did as the regular user. > Curiously, the "escl" version did not work as root,even though when I > run simple-scan without any arguments, it did work as root. At this site, neither simple-scan nor xsane opens a display when run as root. > > > I'm bewildered by this--any idea what I should be looking at? > > > > Yes; there is a possible solution. Give what you get for > > > > lsusb -v | grep -A 3 bInterfaceClass.*7 > > ---$ lsusb -v | grep -A 3 bInterfaceClass.*7Couldn't open device, some > information will be missing bInterfaceClass 7 Printer > bInterfaceSubClass 1 Printer bInterfaceProtocol 4 > iInterface 0 can't get debug descriptor: Resource temporarily > unavailableCouldn't open device, some information will be missingCouldn't > open device, some information will be missing-- bInterfaceClass > 7 Printer bInterfaceSubClass 1 Printer bInterfaceProtocol > 4 iInterface 0 Couldn't open device, some information will > be missingCouldn't open device, some information will be missingcan't get > debug descriptor: Resource temporarily unavailableCouldn't open device, some > information will be missing--- > (The "Couldn't open device" line was repeated multiple times wherever > it appeared;I deleted it here for brevity.) "bInterfaceProtocol 4" indicates that the Canon LiDE 300 understands the IPP-over-USB protocol. > > and > > > > systemctl list-units "ipp-usb*" | grep service > > ---$ systemctl list-units "ipp-usb*" | grep service ipp-usb.service loaded > active running Daemon for IPP over USB printer support--- Indicates that the IPP-over-USB protocol is being used. Install sane-airscan and give scanimage -L and airscan-discover -- Brian.