Alisson Maurilo :
I use fedora 18. I tested these programs, but in all them, my scanner is not recognized. Only appears my webcam as digitizer device. how to solve this?
Check the Fedora forums or IRC channels to see if there is a specific driver package you need to load. Chances are the Fedora repos already have the package available and you just need to figure out its name.
The software that handles the scanner for most programs is SANE. They may have specific instructions for your scanner model:
http://www.sane-project.org
I'm unfamiliar with Fedora but it could also be a permissions problem with the scanner device. Your user account may not have access to it. Check the Fedora documentation to see if there is a specific scanner group that your user account needs to be a member of.
Another common problem is that most scanners require firmware to be loaded into them when they are turned on, very similar to what most wireless NICs require. Normally this is handled by the driver but license restrictions often prevent Linux distributions from including the firmware file. The normal solution is to obtain it from the Windows driver. Sometimes the firmware is wrapped up in a driver file and needs to be extracted using a "firmware cutter" utility.