allan:
I tried to fix it out, I can know this brightness => protcol map from Usbpcap on Windows OS. 0: 0x80 1: 0x81 -1: 0x7f -100: 0x01 100: 0xff sb[0x16] and sb[0x17] is sync. to sane-backends, I can see this #define set_WD_threshold(sb, val) sb[0x16] = val there miss sb[0x17], so I try to force to 0x80(0). I added this in canon_dr.c desc1[0x16] = 0x80; desc1[0x17] = 0x80; with SANE_DEBUG_CANON_DR, I can see brightness number is cool from log. but the image from scanner is also bad. I have no idear for it. I thought it will work fine when I set the brightness value like Windows OS driver. but It wasn't. kangear At 2020-03-21 17:45:49, "Tony" <[email protected]> wrote: Hi allan: there is picture, win7 vs 1.0.24 vs 1.0.29 https://drive.google.com/file/d/19-ahQYcj6TK9ZPtdi2Eh9-V3nImeEzys/view 1.0.24 only little red; 1.0.29 only little brightness problem. And I want to try fix it, if you can help me. I also do some reverse engineered. :P tony At 2020-03-20 08:19:05, "m. allan noah" <[email protected]> wrote: >Thanks for the report. I've been unable to correct the calibration >issues on these scanners in the past, as all the calibration code is >reverse engineered. It would be helpful if someone else could pick it >up and try to improve it. > >allan > >On Thu, Mar 19, 2020 at 10:58 AM Tony <[email protected]> wrote: >> >> Hi all, I tried to test Canon P215II, backend version: 1.0.29. >> >> ./scanimage --format=png > test.png >> > test.png is gray; >> >> ./scanimage --format=png --mode=Color > test.png >> > test.png is color, but seems brightness high. The image looks like adjust >> > brightness to max effect on Windows OS; >> >> ./scanimage --format=png --mode=Color --brightness=-100 > test.png >> > test.png always like that, Maybe brightness option has no effect for now. >> >> And scan speed is slow. >> >> that's all. if you need more, just email me. I'll try to be the best tester. >> :P >> >> kangear > > > >-- >"well, I stand up next to a mountain- and I chop it down with the edge >of my hand"
