[sane-devel] genesys backend

[Pierre Willenbrock]

Hi,

Stéphane VOLTZ schrieb:
> 	Hello,
> 
> 	there are quite some issues with gl646:
> 
> 	- 250, 400 and 500 dpi modes fail with 'invalid argument'.

At least in the log you sent me it fails in gl646_search_start_position,
trying to read the last 64 bytes of a scan. I am not aware of any
changes affecting that function.

> 	- lineart mode is broken .

I could change read_ordered_data to convert gray data to lineart. But
the changes to make the scanner output lineart are small: Set lineart
bit, modify read_bytes_left and words_per_line to correctly take lineart
into account(which would be setting depth correctly).
At least that did the trick for my scanner. I cannot test on a gl646, so
i am just attaching my idea of the changes needed. Please test.

> 	- after a few scan, especially when changing dpi, I get 'color noise' instead 
> of pictures. Restarting the scanning program fix it.

Sounds like memory corruption. Thats always hard to track down..

Regards,
  Pierre
-------------- next part --------------
A non-text attachment was scrubbed...
Name: lineart_gl646.diff
Type: text/x-patch
Size: 630 bytes
Desc: not available
Url : http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20051121/4b8ecaf0/lineart_gl646.bin