Hi again, Dnia Saturday 18 February 2006 17:37, Oliver Schwartz napisa?:
> > You don't need the device nodes. The backend should always use libusb, > which doesn't need the device nodes. You can check what's going on by > running > SANE_DEBUG_SNAPSCAN=255 xsane > done, with success, result is here: http://rmrmg.com/jaroslav/scanner-debug/SANE_DEBUG_SNAPSCAN_255-xsane.log however, I've got strange issues. Sometimes after turning on the scanner works good But sometimes a LED on it starts to pulsate with red light about 15 seconds after the scanner is connected to computer. And then I'm not able to scan: 'sane-find-scanner' finds the device properly, but scanimage/xsane say that no device found. At this moment I'm not sure it this is sane-specific issue, or maybe usb/hotplug/whatever is guilty. -- Jaroslaw Gorny [email protected] -----BEGIN GEEK CODE BLOCK----- Version: 3.12 GMU/E/CS d+/-- s+: a- c++ UL++/US P+>++ L+++>++++ E>++ W N++ o? K w--- !O M V- PS+++ PE++ Y PGP>++ t 5 X- R- tv--/!tv b++ DI-- D G- e++>+++ h-- r+++ z+++ -----END GEEK CODE BLOCK----- -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: not available Url : http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20060218/bb8e3936/attachment.pgp From [email protected] Sun Feb 19 14:48:06 2006 From: [email protected] (Krzysztof Halasa) Date: Sun Feb 19 14:48:21 2006 Subject: [sane-devel] EPSON 3490, calibration and raw data References: <[email protected]> <[email protected]> <[email protected]> Message-ID: <[email protected]> Krzysztof Halasa <[email protected]> writes: > http://www.epson.co.uk/products/scanners/product_spec/Perfection3490Photo.htm > > Not nice, I wouldn't expect that from them. I have changed: #if 0 pc[SET_WINDOW_P_GAMMA_NO] = 0x01; /* downloaded gamma table */ #else pc[SET_WINDOW_P_GAMMA_NO] = 0x00; #endif and now, using 16-bit mode with "255" calibration (BTW the ppm_stat.c program I sent to the list had a bug printing the same "different pixel count" for G and B): test1.ppm: different pixel values: R = 57545 (117-61776) G = 54193 (1002-62775) B = 54548 (2-63413) It's 3192 x 19137 x 16bit (ca. 4 frames of 35 mm negative film at 3200 dpi) and it includes uncovered area (no film at all) and fully-covered (metal film) one. So unless the additional bits come from somewhere else it's really a 16-bit (48-bit) scanner. I just have to figure out how to upload 16-bit gamma table to it (or set it to 1:1, the G and B ranges suggest some correction applied). Of course it doesn't automatically mean that all 16 bits from CCD are usable, at least with a single-pass scanning (I can see some amount of noise with 14-bit) - what I currently want is not a noiseless image but a raw uncorrected data from CCD. BTW: calib-output-8b.ppm: different pixel values: (8-bit raw calibration data) R = 114 (66-234) G = 92 (71-229) B = 92 (75-233) calib-output.ppm: different pixel values: (16-bit data) R = 117 (69-15104) G = 93 (71-14784) B = 93 (74-14976) It looks like the black calibration (lower values, around 70) is the same data in both 8-bit and 16-bit mode (i.e., in 8-bit mode the LSB is present and 6-bit MSB is assumed to be zero). I will experiment with this a bit longer - probably someone has an idea how to set 16-bit gamma tables and/or to set "analog" gamma value (to 1.0) so the scanner doesn't modify the data? Or maybe it's already transparent, i.e., the scanner does no gamma but just brightness and contrast (already set to 128 = neutral)? The peak values are a bit different from the 14-bit calibration data * 4, the range should be something like 280 - 60500. -- Krzysztof Halasa
