[sane-devel] Exif informations

Georges Roux georges.roux@pacageek.org
Sun, 18 May 2003 23:40:29 +0200

I use this device:
device `coolscan2:usb:libusb:001:004' is a Nikon    LS-40 ED         
film scanner

it's a film scanner (USB).
And I would like to have some informations, about  the date, the 
parameters, the version, the author and all that I have
to know about the image and more... if you please. May be it's a dream, 
but yes there is a library who can help to do that.
I use exif command line, to search about somes images, and I think may 
be usefull to retrieve the applied correction.
I don't understand why a scanner can't do less than my digital camera.


Till Kamppeter wrote:

> Is the device which you are using really a scanner?
> If it is a locally (USB, SCSI, parallel, ISA or PCI card) scanner and 
> the Windows driver gives you the possibility to save the scanned image 
> as a JPEG with EXIF info, the EXIF info is most probably generated by 
> the Windows driver, as local scanners usually send raw image data over 
> the wire. In this case it would be an idea of enhancement for SANE or 
> its frontends to save info about the image and or applied correction 
> operations in an EXIF header when saving the image as JPEG.
> If it is a network-connected high-end multi-function device (usually 
> based on an office copy machine) which allows the user to download 
> scans as JPEG files via a web interface, FTP, or e-mail you can apply 
> libexif-based tools on the JPEG files as soon as they are onm your 
> hard disk, see below about these tools.
> If your device is a digital camera (or the small HP PhotoSmart scanner 
> which scans onto a photo memory card) the camera´s firmware stores the 
> camera settings in an EXIF haeder when you let the camera save the 
> photo as JPEG on the memory card. Use gtkam (gphoto2 frontend with 
> remote control feature, http://www.gphoto.org/) or the buttons of the 
> camera to take the photos, then they get saved on the card. If there 
> is a driver for SANE to take or download photos (does this exist?) it 
> is possible that you get the image as raw data, without EXIF header 
> (as from a local scanner). Download the photos via USB mass storage or 
> gphoto2. Then use libexif-base tools for reading and editing the EXIF 
> headers.
> libexif and the "exif" (command line) and "gexif" (graphical) 
> frontends you can find in many distros or on 
> http://sourceforge.net/projects/libexif. In addition, gtkam, gphoto2, 
> flphoto (http://www.easysw.com/~mike/flphoto/), and several web album 
> systems support EXIF (when compiled with libexif).
>    Till