kopia lustrzana https://gitlab.com/sane-project/backends
106 wiersze
3.9 KiB
Plaintext
106 wiersze
3.9 KiB
Plaintext
gt68xx.TODO -*-text-*-
|
|
|
|
General:
|
|
--------
|
|
|
|
- some sort of fixed lookup-table may be necessary to compensate for the
|
|
non-linear CCD/CIS behaviour. A gamma value is not good enough. Or maybe line
|
|
calibration can be used for that?
|
|
- Some Plustek scanners are advertised with e.g. 1200x2400 but the maximum
|
|
vertical resolution seems to be limited to the horizontal one. Check if
|
|
that's really the case.
|
|
- Keep a log of all gain/offset combinations already tested and break if
|
|
one is repeated to avoid endless loops.
|
|
- Print commands that are send to the scanner in clear text.
|
|
- Try to implement non-blocking USB bulk reads, check libusb CVS.
|
|
|
|
CCD:
|
|
----
|
|
|
|
Mustek BearPaw 2400 TA Plus:
|
|
- some lines at the beginning of each image have wrong colors (linedistance?)
|
|
This seems to happen with other scanners, too.
|
|
- 600 dpi no backtrack, 1200, 2400 dpi backtrack (gray), check with windows for
|
|
color
|
|
- 600 dpi 12 bit seems to work in pixel mode only (but long lines are too big!)
|
|
|
|
Mustek BearPaw 1200 TA:
|
|
- similar color problem as 2400 TA Plus, doesn't always happen?
|
|
|
|
Mustek BearPaw 2448 TA Plus:
|
|
- all modes are slow (massive backtracking). If connected to a USB2 port, the
|
|
backtracking ich much less despite this scanner can't do USB2. Strange.
|
|
- Sometimes there is a USB protocol error when cancelling the scan?
|
|
- top borders move with resolution (happened in the early days with 2400 TA!)
|
|
- gray scans have different brightness
|
|
- scan motor is bumpy and freezes sometimes, looks like accelaration is too big
|
|
(firmware problem?)
|
|
- vertical stripes
|
|
- TA settings are wrong
|
|
- no backtrack >= 600 dpi (also gray!)
|
|
- don't move before and after scan
|
|
- check jpeg output, maybe this can be used for faster scans
|
|
|
|
Plustek 1248U:
|
|
- Linedistance seems to have problems in the first few and the last lines.
|
|
- Gain and offset values are quite high. Optimum values are not reached. Problem
|
|
with coarse calib? Better algorithm needed.
|
|
- Images in color mode sometimes look too redish (result of above problem).
|
|
- quite slow when full width is selected. Lots of backtracking.
|
|
- Check if pixel mode is possible.
|
|
- Check again 600x1200 dpi.
|
|
|
|
Plustek U16B:
|
|
- 600 dpi 16 bit is limited to about half the size of the scan area because
|
|
only pixel mode works and 16k is the maximum buffer size.
|
|
- After scanning, a run of sane-find-scanner leads to a protocol error and
|
|
scanning does no longer work.
|
|
|
|
Genius ColorPage Vivid 1200XE
|
|
- 16 bit per color is advertized but this mode doesn't seem to work
|
|
(only 12 bit)?
|
|
- 1200x1200 and 1200x2400 dpi doesn't seem to work despite being advertized
|
|
- Y-positioning varies slightly with resolution (some mm)
|
|
|
|
CIS:
|
|
----
|
|
|
|
- It may be necessary to do an additional exposure calibration before the
|
|
offset/gain calibration to compensate for different intensities of the
|
|
colored leds. Especially for the Mustek 2400 CU Plus.
|
|
- Changing exposure doesn't seem to have any effect during calibration
|
|
sometimes while it has an effect on the final image?
|
|
|
|
Mustek BearPaw 1200 CU
|
|
- ok
|
|
|
|
Mustek BearPaw 1200 CU Plus (0x021b)
|
|
- ok, but similar exposure problems as 2400 CU Plus
|
|
|
|
Mustek BearPaw 2400 CU Plus
|
|
- ok, but exposure setting may need to be done automatically if the intensity
|
|
of the colors varies for different scanners.
|
|
- calibration/exposure has sometimes sharp jumps in intensity. Reason is
|
|
unknown.
|
|
|
|
Mustek ScanExpress A3 USB
|
|
- still slight vert. stripes
|
|
- why is line distance setup necessary?
|
|
- line distance varies with resolution (0,5,5 at 300 dpi, 0, 6, 7 with 150 dpi)
|
|
- exposure doesn't seem to have any effect
|
|
|
|
Mustek ScanExpress 1248 UB
|
|
ok
|
|
|
|
Plustek OpticSlim 2400
|
|
- only upto 1200 dpi vertical works
|
|
- only 8 and 12 bit work, 16 doesn't (check Windows)
|
|
- exposure is extremely high and seems to have similar problems as with other
|
|
CIS scanners (reaches limit also)
|
|
|
|
Mustek ScanExpress 2400 USB
|
|
- make it work (nobody seems to have this device)
|
|
|
|
Visioneer OneTouch 7300
|
|
- 16 bit doesn't seem to work despite beeing advertized
|