7. Installing and Using Scanners

This section explains how to install a scanner through ScannerDrake, and how to use it with SANE and XSane (scanner interface software). We also present a list of other scanner interface software you could use with GNU/Linux.

[Dica]Dica

Please note that not all scanners are supported under GNU/Linux. Before buying new hardware, remember to check out Mandriva's Hardware Database and the SANE home page for compatibility issues.

7.1. Configuring your Scanner

7.1.1. ScannerDrake

 The ScannerDrake wizard helps you install your scanner. Make sure your scanner is powered on and launch ScannerDrake by clicking on the Scanners entry of the Mandriva Linux Control Center's Hardware section.

The program tries to detect your scanner's manufacturer and model. If it finds one information about it is displayed in the upper part of the wizard's main window. Other options are also available (Figura 3.21, “Installing your Scanner”):

Figura 3.21. Installing your Scanner

Installing your Scanner

Click on Search for new scanners to autodetect a new scanner you just plugged in. Click on Add a scanner manually if the automatic detection fails and look for the specific model you own by browsing through the list of available models.

Figura 3.22. The Tree-list of All Known Scanner Models

The Tree-list of All Known Scanner Models

After choosing the appropriate model, you can leave the default Auto-detect available ports option and click on OK. If you have a parallel port scanner, selecting /dev/parport0 in the pull-down list should be the right choice.

Your scanner should now be installed and you should be ready to use the programs which come with SANE, XSane or other acquisition software.

[Atenção]Atenção

Note that HP multi-function devices, such as the OfficeJet and PSC printers, must be configured through PrinterDrake. Please refer to Seção 6, “Configuring Printers with PrinterDrake”. The scanning part of non-HP multi-function devices can be set up with ScannerDrake as a stand-alone scanner.

To test that everything works correctly, launch xscanimage[2] from a terminal and try to acquire a picture from your scanner. You may first acquire a preview of the scanned image by clicking on the Preview window button, as shown in Figura 3.23, “Acquiring Images with xscanimage”.

Figura 3.23. Acquiring Images with xscanimage

Acquiring Images with xscanimage

Note that xscanimage can also be launched directly from GIMP by choosing File+Acquire+xscanimageDevice dialog.

ScannerDrake allows for scanner sharing between users connected via a LAN. Installation is very easy: just click on Scanner sharing and either select The scanners on this machine are available to other computers or Use scanners on remote computers depending on what you want to do. With these buttons you can define which machines are allowed to use your scanners and which remote scanners you want to use.

Figura 3.24. Sharing Scanners within a LAN

Sharing Scanners within a LAN
[Nota]Nota

In order to share your scanner on your LAN, the saned package needs to be installed. If it isn't, ScannerDrake will ask you if you want to install it. You also need to set up scanner sharing on the machines from which you want to access the scanner. Check the Use scanners on remote computers box, and then click on Add host. Fill in the information in the Name/IP address of host field for each of the machines which scanners.

7.2. Using Image Acquisition Software

7.2.1. XSane

While xscanimage is more than enough for your basic scanning needs, more experienced and/or graphic-oriented users will want to use a more sophisticated program. XSane[3] offers more options and a more informative display during the image acquisition process.

You can launch XSane through the Multimedia+GraphicsXSane menu item. Several windows pop up on your screen.

Figura 3.25. XSane Multiple Windows

XSane Multiple Windows
[Nota]Nota

If the xsane-gimp package is installed, a GIMP plugin will be at your disposal. It allows you to import your images directly into GIMP for image retouching tasks. Choose File+Acquire XSane: device dialog to launch XSane. You can now scan your image and have it sent directly to GIMP.

7.3. Advanced Configuration

7.3.1. Fine-Tuning the Resolution

Most modern scanners boast high resolutions, such as 1200, 1600 or 2400 DPI (Dots Per Inch). But it would be a mistake to perform all of your scanning at the maximum available resolution. You will notice very little — if any — quality difference between a 300 and a 600 DPI image scan, but the file size will grow exponentially, up to many MBs of disk space for a single image file.

The resolution value should be chosen according to the device on which the image is to be reproduced. For images to be viewed on computer monitors, e.g. for web sites, the resolution should be close to typical monitor resolution values, between 70 and 100 DPI. Higher values will result not only in bigger images, but the dimensions will also increase, so that an image scanned at 160 DPI instead of 80 will be about twice as large[4].

If you intend to print your images, a resolution of 300 DPI should be enough for most home printers. Increase this value if you have a very high quality printer.

Higher values should be chosen only for specific uses, such as enlarged images on very high quality printers, or quality scans of black and white originals. You will have to experiment a little until you're satisfied with the results.

7.3.2. OCR Software

By installing the kdegraphics-kooka and ocrad packages, you'll be able to use Kooka, a simple graphical front-end to SANE which is also able to perform OCR tasks. To launch it, choose Multimedia+GraphicsKooka from the main menu.

First choose the scanning device and then Kooka's main window appears.

Figura 3.26. Kooka's Main Window

Kooka's Main Window

Place the image you want to scan onto your scanner and click on Preview Scan at the bottom left of Kooka's window. For better results, you should choose the Grayscale Scan mode. Then adjust the resolution (200 DPI should be enough), select the part of the image to be scanned and click on Final Scan.

To benefit from Kooka's OCR features, you must configure it. Access the SettingsConfigure Kooka menu, click on OCR, and select the OCR engine you want to use.

Figura 3.27. Kooka's Configuration Window

Kooka's Configuration Window

 Once this is done you can click on this icon (ImageOCR Image) and click on Start OCR. The resulting text will appear along with a spell-correction window.

[Nota]Nota

Kooka is still in beta phase. Although it's possible to make it work properly you will need to adjust its parameters until you obtain a decent rendering. For more information on Kooka please read its handbook (HelpKooka Handbook).

7.4. Other Scanner Interface Software

Here is a list of other scanner interface software which is known to work under GNU/Linux.

  • Users of the FLTK (“Fast Light Tool Kit”) graphic user interface could try FlScan, a FLTK front-end for SANE.

  • For EPSON scanners, you could download Image Scan! for Linux, a scanner utility provided free of charge to GNU/Linux users by EPSON KOWA Corporation.

  • While multi-functional HP devices are configured using PrinterDrake, owners of these devices should have a look at the HP Linux Inkjet Project. The developers involved in the project aim at providing GNU/Linux support for most Hewlett-Packard OfficeJet, PSC, LaserJet, and PhotoSmart printer multi-function peripherals (MFPs).



[2] The sane-frontends package must be installed.

[3] The xsane package must be installed.

[4] However scanning at a higher resolution and then reducing the resulting image size using graphic manipulation software such as GIMP is one method often used to obtain better results than directly scanning at the desired final resolution.