Hi, On Thu, Jun 09, 2005 at 04:47:05PM +0200, Giuseppe Sacco wrote: > Basically I do a scan of 210.0x297.0mm, using a 200dpi resolution. > Prior to scan I call get_parameters and receive an *estimated* values > for lines, pixelsperline, bytesperline; after receiving this data I > receive the frame data.
Which frontend do you use? > while, when scanning, I get a different amount of data: This is perfectly legal (see SANE standard). The normal way is: sane_get_parameters (returns estimated values) sane_start sane_get_parameters (returns exact parameters) --> malloc memory for image, ... > I see two possible options: > > 1. Change the snapscan algorithm to have better supposed values If snapscan doesn't return the correct parameters after sane_start, it's broken. But I'd be very surprised if that were the case as that would break all frontends. > 2. Change the sane network protocol in order to get all corrected > parameter *with* or *after* the scanned data. I haven't checked that but you can get the parameters after running sane_start, can't you? You can test the behaviour of frontends concerning the estimated parameters with the "test" backend (use option "fuzzy parameters"). Bye, Henning