It is a workflow oriented photo retouching software with all necessary tools to quickly process camera raw images. For this purpose GTKRawGallery brings together the most powerfull open source tools existing to work with 16 bit color depth images: Dcraw, Imagemagick and Exiftool. It is also a full featured photo manager for most popular image formats.

Here is a summary list:

• Image browser and album manager;
• Full featured Dcraw GUI for a fine-tuned raw image pre-processing;
• Image modification tools for 16 bit/channel post-processing;
• Batch conversion with styles;
• Batch Processor to speed up workflow;
• Fast tagging;
• Advanced Metadata Editor with EXIF, IPTC and XMP write support;
• Color Management;
• Print support;
• Facebook, Flickr and Picasa Web Albums Publisher;
• Dropbox Uploader;

Popular formats: jpeg, tiff, gif, png, bmp, emf, apm, wmf, cur, ico, qif, qtif, icns, pcx, targa, tga, xbm, xpm, ras, ppm, pgm, pbm, pnm, wbmp, ani.
Camera raw files: cr2, nef, crw, raf, kdc, dcr, mrw, sr2, orf, ptx, pef, arw, srf, x3f, erf, dng, bay, bmq, cs1, dc2, fff, k25, mos, rdc, rw2, 3fr, ari, cap, iiq, eip, dcs, drf, mef, nrw, pxn, r3d, raw, rw1, rwz.
So you can manage a raw image like a jpeg or tiff :-)

Wow! Is it for free?

Yes.

How is it licensed?

GTKRawGallery is an open source project released with the GNU GPL 3 license.

Then only for Linux?

No, it runs on Windows XP, Vista and Seven too.