Quick Image Viewer is a small and fast GDK/Imlib2 image viewer. Features include zoom, maxpect, scale down, fullscreen, slideshow, delete, brightness/contrast/gamma correction, pan with keyboard and mouse, flip, rotate left/right, jump/forward/backward images, filename filter and use it to set X desktop background.

gpicview is a lightweight GTK+ 2.x based image viewer. It is the default image viewer on LXDE desktop environment.

MComix is a customizable image viewer that specializes as a comic and manga reader. It supports a variety of container formats including CBZ, CB7, CBT, LHA.

For PDF support, install the mupdf package.

Nomacs is a simple to use image lounge featuring semi-transparent widgets that display additional information such as metadata, thumbnails and histograms. It is able to browse images compressed archives and add notes to images.

Nomacs includes image manipulation methods for adjusting brightness, contrast, saturation, hue, gamma, and exposure. It has a pseudo color function which allows creating false color images. A unique feature of Nomacs is the synchronization of multiple instances.

Überzug is a command line util which draws images on terminals by using child windows. The advantages of using Überzug are:

• No race conditions as a new window is created to display images.

• Expose events will be processed, so images will be redrawn on switch workspaces.

• Tmux support (excluding multi pane windows).

• Terminals without the WINDOWID environment variable are supported.

• Chars are used as position - and size unit.

• No memory leak (/ unlimited cache).

Überzug is a command line util which draws images on terminals by using child windows. The advantages of using Überzug are:

• No race conditions as a new window is created to display images.

• Expose events will be processed, so images will be redrawn on switch workspaces.

• Tmux support (excluding multi pane windows).

• Terminals without the WINDOWID environment variable are supported.

• Chars are used as position - and size unit.

• No memory leak (/ unlimited cache).

Swayimg is a fully customizable and lightweight image viewer for Wayland based display servers. It supports the most popular image formats (JPEG, JPEG XL, PNG, GIF, SVG, WebP, HEIF/AVIF, AV1F/AVIFS, TIFF, EXR, BMP, PNM, TGA, QOI, DICOM, Farbfeld). It has fully customizable keyboard bindings, colors, and many other parameters. It also supports loading images from files and pipes, and provides gallery and viewer modes with slideshow and animation support. It also includes a Sway integration mode: the application creates an overlay above the currently active window, which gives the illusion that you are opening the image directly in a terminal window.

Qimgv is a configurable Qt image viewer, with optional video support.

sxiv is an alternative to feh and qiv. Its primary goal is to provide the most basic features required for fast image viewing. It has vi key bindings and works nicely with tiling window managers. Its code base should be kept small and clean to make it easy for you to dig into it and customize it for your needs.

Chafa is a command-line utility that converts all kinds of images, including animated GIFs, into ANSI/Unicode character output that can be displayed in a terminal.

Catimg is a little program that prints images in the terminal. It supports JPEG, PNG and GIF formats.

Luminance HDR (formerly QtPFSGui) is a graphical user interface application that aims to provide a workflow for high dynamic range (HDR) imaging. It supports several HDR and LDR image formats, and it can:

• Create an HDR file from a set of images (formats: JPEG, TIFF 8bit and 16bit, RAW) of the same scene taken at different exposure setting;

• Save load HDR images;

• Rotate, resize and crop HDR images;

• Tone-map HDR images;

• Copy EXIF data between sets of images.

PIXterm shows images directly in your terminal, recreating the pixels through a combination of ANSI character background color and the unicode lower half block element. It supports JPEG, PNG, GIF, BMP, TIFF and WebP.

qView is a Qt image viewer designed with visually minimalism and usability in mind. Its features include animated GIF controls, file history, rotation/mirroring, and multithreaded preloading.

qpageview provides a page based document viewer widget for Qt and PyQt. It has a flexible architecture potentionally supporting many formats. Currently, it supports SVG documents, images, and, using the Poppler-Qt5 binding, PDF documents.

ytfzf is a POSIX script that helps you find PeerTube or YouTube videos without requiring API and opens/downloads them using mpv/ytdl.

imv is a command line image viewer intended for use with tiling window managers. Features include:

• Native Wayland and X11 support.

• Support for dozens of image formats including:

  • PNG

  • JPEG

  • Animated GIFs

  • SVG

  • TIFF

  • Various RAW formats

  • Photoshop PSD files

• Configurable key bindings and behavior.

• Highly scriptable with IPC via imv-msg.

Leptonica is a C library and set of command-line tools for efficient image processing and image analysis operations. It supports rasterop, affine transformations, binary and grayscale morphology, rank order, and convolution, seedfill and connected components, image transformations combining changes in scale and pixel depth, and pixelwise masking, blending, enhancement, and arithmetic ops.

Developer's Image Library (DevIL) is a library to develop applications with support for many types of images. DevIL can load, save, convert, manipulate, filter and display a wide variety of image formats.

APNG (Animated Portable Network Graphics) is an unofficial extension of the APNG (Portable Network Graphics) format. APNG patch provides APNG support to libpng.

OpenJPEG is an implementation of JPEG 2000 codec written in C language. It has been developed in order to promote the use of JPEG 2000, a still-image compression standard from the Joint Photographic Experts Group (JPEG). Since April 2015, it is officially recognized by ISO/IEC and ITU-T as a JPEG 2000 Reference Software.

PerceptualDiff visually compares two images to determine whether they look alike. It uses a computational model of the human visual system to detect similarities. This allows it too see beyond irrelevant differences in file encoding, image quality, and other small variations.

JBIG2 is designed for lossy or lossless encoding of bilevel (1-bit monochrome) images at moderately high resolution, and in particular scanned paper documents. In this domain it is very efficient, offering compression ratios on the order of 100:1.

This is a decoder only implementation, and currently is in the alpha stage, meaning it doesn't completely work yet. However, it is maintaining parity with available encoders, so it is useful for real work.

Libtiff provides support for the Tag Image File Format (TIFF), a format used for storing image data. Included are a library, libtiff, for reading and writing TIFF and a small collection of tools for doing simple manipulations of TIFF images.