Hi, [email protected] writes:
> Hi, > > thank you for your hints. I reconnected the book scanner and was now > recognized as video2. The number is likely to change between power-cycling of the device. > scanimage --list-devices > device `v4l:/dev/video2' is a Noname JY-VP216: JY-VP216 virtual device > device `v4l:/dev/video0' is a Noname USB2.0 HD UVC WebCam: USB2.0 HD > virtual device > > Then I tried > > scanimage -d v4l:/dev/video2 --help --all-options > > with result > > Usage: scanimage [OPTION]... > Start image acquisition on a scanner device and write image data to > standard output. > [...] > Options specific to device `v4l:/dev/video2': > Scan Mode: > --mode Gray|Color [Gray] > Selects the scan mode (e.g., lineart, monochrome, or color). > --channel Camera 1 [inactive] > Selects the channel of the v4l device (e.g. television or video-in. > Geometry: > -l 0..-513pel (in steps of 1) [inactive] > Top-left x position of scan area. > -t 0..-209pel (in steps of 1) [inactive] > Top-left y position of scan area. > -x 1280..767pel (in steps of 1) [inactive] > Width of scan-area. > -y 720..511pel (in steps of 1) [inactive] > Height of scan-area. > Enhancement: > --brightness 0..255 [102] > Controls the brightness of the acquired image. > --hue 0..255 [0] > Controls the "hue" (blue-level) of the acquired image. > --color 0..255 [119] > Sets the picture's color. > --contrast 0..255 [136] > Controls the contrast of the acquired image. > --white-level 0..255 [0] > Selects what radiance level should be considered "white". > > All options specific to device `v4l:/dev/video2': > [same output ...] > > Geometry settings seem not to be supported by V4L module. > > I also tried successlessly > > SANE_DEBUG_V4L=128 scanimage -v -d v4l*/dev/video2 > Output format is not set, using pnm as a default. > scanimage: open of device v4l*/dev/video2 failed: Invalid argument Is that asterisk a typo in your command? It should be a colon. Whoops, I now see that typo was in my suggestion. Sorry. # That's what I get for mixing Japanese and US ASCII keyboards. > Regards, > > --- > > Michael Dittmer > > FSFE fellower > > Am 2020-09-06 um 08:18 schrieb Olaf Meeuwissen: >> Hi, >> >> Suggestions inlined below. >> >> [email protected] writes: >> >>> ---------- Ursprüngliche Nachricht ---------- >>> Von: Michael Dittmer >>> An:"[email protected]" >>> <[email protected]> >>> Datum: 23.08.2020 12:00 >>> Betreff: book scanner recognized as v4l device >>> >>> I bought a book scanner >>> >>> JOURIST BT16 >>> >>> from a german dealer >>> >>> looks like: >>> http://www.scanner.expert/de/images/products/buchscanner/description/5_JOURIST_Buchscanner_BS16_Standalone.jpg >>> >>> >>> It takes photos from the pages with a camera like a CZUR book >>> scanner. My bookscanner camera also can be opened by >>> >>> guvcview >>> >>> It has maximum resolution of >>> >>> 4608x3456 >>> >>> pixels for A3 scan (resolution can be selected by gucview and is shown >>> later when starting xsane). >>> >>> When I plug it onto a usb port, several devices are recognized (dmesg >>> output) >>> >>> [...] >>> >>> All book scanner manufacturers seem to deliver only twain drivers. So >>> I tried to handle the scanner as an generic v4l device >>> >>> My linux mint 19.3 (based on Ubuntu 18.04) distribution has a sane >>> backend package (1.0.27) without compiled v4l backend. >>> After compiling current 1.0.30 sources with v4l-dev libraries I >>> obtained the v4l backend >>> >>> scanimage --list-devices >>> device `v4l:/dev/video3' is a Noname JY-VP216: JY-VP216 virtual device >>> >>> but xsane and scanimage are not able to perform scan ("illegal argument") >> Check the supported settings and allowed values with >> >> scanimage -d v4l:/dev/video3 --help --all-options >> >>> SANE_DEBUG_SANEI_USB=4 scanimage -v -d v4l:/dev/video3 --format tiff > >>> output.tif >>> scanimage: ignored request to set inactive option br-x >>> scanimage: ignored request to set inactive option br-y >>> scanimage: sane_start: Invalid argument >> Try >> >> SANE_DEBUG_V4L=128 scanimage -v -d v4l*/dev/video3 >> >> and see if that sheds any light upon your issue. >> >>> Another program >>> >>> simple scan >>> >>> from Ubuntu distribution is able to scan into pdf with 1600x1200 pixel >>> but not with maximum resolution. >>> >>> It seems for me that the v4l backend has to support higher >>> resolutions, like 4608x3456 e.g. Hope this helps, -- Olaf Meeuwissen, LPIC-2 FSF Associate Member since 2004-01-27 GnuPG key: F84A2DD9/B3C0 2F47 EA19 64F4 9F13 F43E B8A4 A88A F84A 2DD9 Support Free Software https://my.fsf.org/donate Join the Free Software Foundation https://my.fsf.org/join
