qiv (Quick Image Viewer)

Quick Image Viewer (qiv) is a very small and pretty fast GDK3 image
viewer. Features include zoom, maxpect, scale down, fullscreen,
brightness/contrast/gamma correction, slideshow, pan with keyboard and
mouse, rotate left/right, flip, delete (move to .qiv-trash/), jump to
image x, jump forward/backward x images, filename filter, and you can
use qiv to set your X11 desktop background.

These formats are supported by default:

GIF TIFF XPM PNG PPM PNM PGM BMP JPEG SVG ICO TGA ICNS

Optional supported formats:

Format                  | Optional dependenc(y|ies)
------------------------+-----------------------------------------------
HEIF, AVIF              | libheif
------------------------+-----------------------------------------------
JP2 (JPEG2000)          | jp2-pixbuf-loader
------------------------+-----------------------------------------------
PCX                     | pcx-pixbuf-loader
------------------------+-----------------------------------------------
PSD (PhotoShop native)  | gdk-pixbuf-psd
------------------------+-----------------------------------------------
RAW (camera images,     | libopenraw. Note that only a few raw image
    various extensions) | formats will actually display with qiv. These
                        | include .crw (Canon), .erf (Epson), and
                        | .nef (Nikon). YMMV.
------------------------+-----------------------------------------------
WEBP                    | webp-pixbuf-loader
------------------------+-----------------------------------------------
WMF (Windows MetaFile)  | libwmf-type1-fonts (only needed for .wmf files
                        | with embedded text, but all the ones I tested
                        | do have text...)
------------------------+-----------------------------------------------
XCF (Gimp native)       | xcf-pixbuf-loader
------------------------+-----------------------------------------------

These are runtime dependencies, so they can be installed at any time
without rebuilding qiv.

To easily build all the optional dependencies, use sbopkg with the
qiv-allfmt.sqf in the SlackBuild directory.

Upgrade note: Starting with version 3.0.0, qiv no longer uses
imlib2. If you have images that would display in qiv-2.3.x, but not in
3.0.x, *please* contact the SlackBuild maintainer, so I can fix it!