gThumb is an image viewer and browser for the GNOME Desktop. It also includes an importer tool for transferring photos from cameras.

gThumb allows the filesystem to be browsed for images. They can be organized into catalogs, or viewed as a slideshow. Folders and catalogs can be bookmarked, and comments can be added to images.

Via gPhoto it can also acquire data directly from digital cameras.

gThumb offers a certain range of image editing operations suited for digital photography, such as the change of image hue, saturation, lightness, contrast or the adjustment of colors and sharpness. It can also crop, scale and rotate images by 90° or custom angles, and it features a red-eye effect removal function. Manipulated images can be saved in the formats JPEG, PNG, TIFF and TGA.

gThumb can export web-based photograph albums with various theme templates. These albums can be uploaded to a website, providing a very simple mechanism for publishing collections of photos on the web.

gThumb also includes many basic features such as copying, moving, deleting or duplicating images, printing, zooming, format transcoding, and batch renaming.

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