Hi I spent some time on fixing the last few bugs in the gl841 part known to me and preparing the backend for the final inclusion of gl841 support needed for my scanner.
The attached patch primarily adds yet another shading calibration method, using the black and white strips at the top of the scanning area. It also adds support for led exposure calibration needed for cis scanners and instant power saving features. The latter is needed because my scanner uses some gpio to completely shut down some circuits like motor drivers and led drivers. The function slot is called from sane_start and sane_cancel, as these seem to be the functions at the begin and end of each scan. The version in the patch mainly shuts down the afe. The patch is not a full patch to get a Canon LiDE 35/50 scanner to work. There is a patch on my private webspace which does that(see below). Regarding the problem of the scanner not delivering any data i found that it's only a problem of the first read after opening the scanner. So my solution is to prepare a simple one line read, setting the usb timeout to 1 second and then read, without checking the result(timeout is reset to 30s afterwards). If the transmission fails, the scanner will still think it succeeded, and later reads will work. It is not clear to me why the scanner sometimes missends the first bulk transfer originated from the scanner, but i suspect a bad usb transmission, although the transfer does not generate any log messages. I tried to implement real lineart, and got it to work most of the time. It was a matter of setting the scanner to do lineart and then simply pass the data on to the frontend, inverting all bits. There are still some combinations of settings which may lead to a failed scan, as there are some more complicated things still missing(stagger correction, line shrinking). Powersaving for the Canon LiDE 35(and hopefuly LiDE 50) works now, too. I don't know if it is complete, but i could not measure a difference between the scanner just plugged in and after a scan. My measuring method was rather inaccurate, so i may be missing something. As always a full patch to get Canon LiDE 35/50 to work can be found here(will be updated to match experimental cvs): http://www.pirsoft-dsl-dropzone.de/genesys_gl841.diff.bz2 It is now ready to be extensively tested. I guess using lineart will reveal some problems, as mentioned above. But i stress tested the color and gray modes to some extend using xsane and zooming the preview. Regards, Pierre -------------- next part -------------- A non-text attachment was scrubbed... Name: genesys_calibration.diff.gz Type: application/x-gzip Size: 6525 bytes Desc: not available Url : http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20050923/1a0204aa/genesys_calibration.diff.bin From x.mo...@gmail.com Fri Sep 23 23:20:38 2005 From: x.mo...@gmail.com (Martin Haag) Date: Fri Sep 23 23:21:03 2005 Subject: [sane-devel] USB recordings MD6190 available Message-ID: <f9a986b805092316207bc6f...@mail.gmail.com> Hi, I've recorded some USB traffic with SniffUSB from the Medion MD6190 scanner tonight. I am going to analyse them in the near future, but if one can't wait the scans are available on http://mibix.de/wiki/index.php/MD6190_USB_Recording . By the way, maybe someone can give me some hints how to analyse such a huge amount of data :) I thought about comparing always two of the files with a block orientated compare tool such as beyond compare on wind-ws. ( hm I can't belive that I sayed this. Ok let's use diff *g* ) cya Martin Haag -- http://mibix.de mailto:x.mo...@gmail.com
