Hi, dear SANE developers! Proposed patch enable support of 50/150/600dpi Color/Gray/LineArt modes for Hewlett-Packard ScanJet 2400 scanner.
This was made by parsing UsbSnoop logs with stef's scripts (thank you!). 100/300dpi modes were already good, so I didn't touch them. I have also refined sensor and motor values for 1200dpi modes, but there are some problems with them. Here is a list of remaining problems I can't solve: 1. 1200dpi Gray mode works, but the resulting image is interlaced vertically with black one-pixel width lines. Why this can happen? Example: http://lion-simba.github.com/1200dpi_gray_lines.tiff 2. 1200dpi Color mode works, but very slow. Scanner warm-up and calibration takes approx 5 mins before head even moves. Then, when scanning begins, head moves forward and backward each few lines. I have made timestamped logs of this situation (truncated log attached). You can see - problem is in "gl646_bulk_read_data" which regularly hangs for approx 10 seconds like this: during warm-up and calibration: --------------------- 1307470777: [genesys_gl646] gl646_bulk_read_data: trying to read 65472 bytes of data 1307470778: [genesys_gl646] gl646_bulk_read_data read 65472 bytes, 679896 remaining 1307470778: [genesys_gl646] gl646_bulk_read_data: trying to read 65472 bytes of data 1307470778: [genesys_gl646] gl646_bulk_read_data read 65472 bytes, 614424 remaining 1307470778: [genesys_gl646] gl646_bulk_read_data: trying to read 65472 bytes of data [9 seconds delay] 1307470787: [genesys_gl646] gl646_bulk_read_data read 65472 bytes, 548952 remaining 1307470787: [genesys_gl646] gl646_bulk_read_data: trying to read 65472 bytes of data 1307470787: [genesys_gl646] gl646_bulk_read_data read 65472 bytes, 483480 remaining --------------------- during scan: --------------------- 1307471061: [genesys_gl646] gl646_bulk_read_data: requesting 30464 bytes 1307471061: [genesys_gl646] gl646_bulk_read_data: trying to read 30464 bytes of data [9 seconds delay] 1307471070: [genesys_gl646] gl646_bulk_read_data read 30464 bytes, 0 remaining 1307471070: [genesys_gl646] gl646_bulk_read_data: end --------------------- Any ideas of what is wrong? Proprietary driver running on the same system scan well in 1200dpi Color, so I think this is not libusb bug. Maybe some GL646 miscofiguration? 3. In all modes, there are extra pixels to the left of the image, which are beyond of glass window of scanner. Meanwhile, right side of image is cropped by (i guess) same number of pixels. I think it can be fixed by tuning CCD_start_xoffset/dummy_pixel/sensor_pixels in Genesys_Sensor, but I'm unsure what is for exactly? What is dummy_pixel? Regards, Alexey. -------------- next part -------------- A non-text attachment was scrubbed... Name: genesys-hp2400-50_150_600_1200dpi.patch Type: text/x-patch Size: 5164 bytes Desc: not available URL: <http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20110608/078f1bff/attachment-0002.bin> -------------- next part -------------- A non-text attachment was scrubbed... Name: 1200dpi_color.log.trunc.gz Type: application/x-gzip Size: 57714 bytes Desc: not available URL: <http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20110608/078f1bff/attachment-0003.bin>
