1gt68xx.TODO -*-text-*- 2 3General: 4-------- 5 6- some sort of fixed lookup-table may be necessary to compensate for the 7 non-linear CCD/CIS behaviour. A gamma value is not good enough. Or maybe line 8 calibration can be used for that? 9- Some Plustek scanners are advertised with e.g. 1200x2400 but the maximum 10 vertical resolution seems to be limited to the horizontal one. Check if 11 that's really the case. 12- Keep a log of all gain/offset combinations already tested and break if 13 one is repeated to avoid endless loops. 14- Print commands that are send to the scanner in clear text. 15- Try to implement non-blocking USB bulk reads, check libusb CVS. 16 17CCD: 18---- 19 20Mustek BearPaw 2400 TA Plus: 21- some lines at the beginning of each image have wrong colors (linedistance?) 22 This seems to happen with other scanners, too. 23- 600 dpi no backtrack, 1200, 2400 dpi backtrack (gray), check with windows for 24 color 25- 600 dpi 12 bit seems to work in pixel mode only (but long lines are too big!) 26 27Mustek BearPaw 1200 TA: 28- similar color problem as 2400 TA Plus, doesn't always happen? 29 30Mustek BearPaw 2448 TA Plus: 31- all modes are slow (massive backtracking). If connected to a USB2 port, the 32 backtracking ich much less despite this scanner can't do USB2. Strange. 33- Sometimes there is a USB protocol error when cancelling the scan? 34- top borders move with resolution (happened in the early days with 2400 TA!) 35- gray scans have different brightness 36- scan motor is bumpy and freezes sometimes, looks like acceleration is too big 37 (firmware problem?) 38- vertical stripes 39- TA settings are wrong 40- no backtrack >= 600 dpi (also gray!) 41- don't move before and after scan 42- check jpeg output, maybe this can be used for faster scans 43 44Plustek 1248U: 45- Linedistance seems to have problems in the first few and the last lines. 46- Gain and offset values are quite high. Optimum values are not reached. Problem 47 with coarse calib? Better algorithm needed. 48- Images in color mode sometimes look too redish (result of above problem). 49- quite slow when full width is selected. Lots of backtracking. 50- Check if pixel mode is possible. 51- Check again 600x1200 dpi. 52 53Plustek U16B: 54- 600 dpi 16 bit is limited to about half the size of the scan area because 55 only pixel mode works and 16k is the maximum buffer size. 56- After scanning, a run of sane-find-scanner leads to a protocol error and 57 scanning does no longer work. 58 59Genius ColorPage Vivid 1200XE 60- 16 bit per color is advertized but this mode doesn't seem to work 61 (only 12 bit)? 62- 1200x1200 and 1200x2400 dpi doesn't seem to work despite being advertized 63- Y-positioning varies slightly with resolution (some mm) 64 65CIS: 66---- 67 68- It may be necessary to do an additional exposure calibration before the 69 offset/gain calibration to compensate for different intensities of the 70 colored leds. Especially for the Mustek 2400 CU Plus. 71- Changing exposure doesn't seem to have any effect during calibration 72 sometimes while it has an effect on the final image? 73 74Mustek BearPaw 1200 CU 75- ok 76 77Mustek BearPaw 1200 CU Plus (0x021b) 78- ok, but similar exposure problems as 2400 CU Plus 79 80Mustek BearPaw 2400 CU Plus 81- ok, but exposure setting may need to be done automatically if the intensity 82 of the colors varies for different scanners. 83- calibration/exposure has sometimes sharp jumps in intensity. Reason is 84 unknown. 85 86Mustek ScanExpress A3 USB 87- still slight vert. stripes 88- why is line distance setup necessary? 89- line distance varies with resolution (0,5,5 at 300 dpi, 0, 6, 7 with 150 dpi) 90- exposure doesn't seem to have any effect 91 92Mustek ScanExpress 1248 UB 93ok 94 95Plustek OpticSlim 2400 96- only up to 1200 dpi vertical works 97- only 8 and 12 bit work, 16 doesn't (check Windows) 98- exposure is extremely high and seems to have similar problems as with other 99 CIS scanners (reaches limit also) 100 101Mustek ScanExpress 2400 USB 102- make it work (nobody seems to have this device) 103 104Visioneer OneTouch 7300 105- 16 bit doesn't seem to work despite being advertized 106