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Terminal Image and Video Viewer

License: GPL v2   Ubuntu Build macOS Build macOS Brew Building HEAD

A user-friendly terminal image viewer that uses graphic capabilities of terminals (Sixel, Kitty or iterm2), or 24-Bit color capabilities and unicode character blocks if these are not available.

On terminals that implement the sixel protocol, the Kitty Graphics Protocol, or the iTerm2 Graphics Protocol this displays images in full resolution.

But even the fallback block display is usable.

Displays regular images, plays animated gifs, scrolls static images and plays videos.

Useful if you want to have a quick visual check without leaving the comfort of your shell and having to start a bulky image viewer. Sometimes this is the only way if your terminal is connected remotely via ssh. And of course if you don't need the resolution. While icons typically fit pixel-perfect, larger images are scaled down to match the resolution.

The command line accepts any number of image/video filenames that it shows in sequence one per page or in a grid in multiple columns, depending on your choice of --grid. The output is emitted in-line with minimally messing with your terminal, so you can simply go back in history using your terminals' scroll-bar (Or redirecting the output to a file allows you to later simply cat that file to your terminal. Even less -R seems to be happy with it).

Pixelation

On a regular terminal, block-characters are used to output images. Half blocks present pixels color-accurately, and quarter blocks provide a higher spatial resolution at the expense of slightly worse color accuracy. These modes should be compatible with most common terminals that support UTF8 and 24Bit color.

If you are on a Kitty, iTerm2, or wezterm terminal, or a terminal that supports the sixel protocol, images can be shown in full resolution.

-p kitty, -p iterm2, or -p sixel -p quarter -p half

Grid display

Images can be shown in a grid, which is very useful if you quickly want to browse through a lot of images. You can choose to show the filename as title, so it is easy to find exactly the filename you're looking for (The following grid uses --grid=2 and is pixelated -p iterm2).

Grid view of 4 pictures

This is how the same grid looks if no high-res mode is available with - `-p quarter` ...

Synopsis

usage: timg [options] <image/video> [<image/video>...]
Options (most common first):
        -p<pixelation> : Pixelation: 'h' = half blocks    'q' = quarter blocks
                                     'k' = kitty graphics 'i' = iTerm2 graphics
                                     's' = sixel graphics
                         Default: Auto-detect graphics, otherwise 'quarter'.
        --grid=<cols>[x<rows>] : Arrange images in a grid ("contact sheet").
        -C, --center   : Center image horizontally in available cell.
        --title[=<fmt_str>]: Print title above each image. Accepts the following
                         format parameters: %f = full filename; %b = basename
                                            %w = image width; %h = height
                                            %D = internal decoder used
                         If no parameter is given, defaults to "%f"
                         Env-var override with TIMG_DEFAULT_TITLE
        -f<filelist>   : Read newline-separated list of image files to show.
                         Relative filenames are relative to current directory.
                         (-f and -F can be provided multiple times.)
        -F<filelist>   : like -f, but relative filenames considered relative
                         to the directory containing the filelist.
        -b<str>        : Background color to use behind alpha channel. Format
                         color name like 'yellow', '#rrggbb', 'auto' or 'none'.
                        'auto' is terminal background color. (default 'auto').
        -B<str>        : Checkerboard pattern color to use on alpha.
        --pattern-size=<n> : Integer factor scale of the checkerboard pattern.
        --auto-crop[=<pre-crop>] : Crop away all same-color pixels around image.
                         The optional pre-crop is the width of border to
                         remove beforehand to get rid of an uneven border.
        --rotate=<exif|off> : Rotate according to included exif orientation.
                              or 'off'. Default: exif.
        -W, --fit-width: Scale to fit width of available space, even if it
                         exceeds height.
        -U, --upscale[=i]: Allow Upscaling. If an image is smaller than the
                         available frame (e.g. an icon), enlarge it to fit.
                         Optional parameter 'i' only enlarges in integer steps.
        --clear[=every]: Clear draw area first. Optional argument 'every' will
                         clear before every image (useful with -w/-wr,
                         but not with --grid)
        -V             : Directly use Video subsystem. Don't probe image
                         decoding first (useful, if you stream video from stdin)
        -I             : Only  use Image subsystem. Don't attempt video decoding
        -w<seconds>    : Wait time between images (default: 0.0).
        -wr<seconds>   : like above, but wait time between rows in grid.
        -a             : Switch off anti-aliasing (default: on).
        -g<w>x<h>      : Output geometry in character cells. Partial geometry
                         leaving out one value -g<w>x or -gx<h> is possible,
                         the other value it then derived from the terminal size.
                         Default derived from terminal size is 160x50
        -o<outfile>    : Write to <outfile> instead of stdout.
        -E             : Don't hide the cursor while showing images.
        --compress[=level]: Only for -pk or -pi: Compress image data. More
                         CPU use, but less used bandwidth. (default: 1)
        --threads=<n>  : Run image decoding in parallel with n threads
                         (Default 3, 3/4 #cores on this machine)
        --color8       : Choose 8 bit color mode for -ph or -pq
        --version      : Print detailed version including used libraries.
                         (v1.5.3+)
        --verbose      : Print some stats after images shown.
        -h             : Print this help and exit.
        --help         : Page through detailed manpage-like help and exit.

  Scrolling
        --scroll[=<ms>]       : Scroll horizontally (optionally: delay ms (60)).
        --delta-move=<dx:dy>  : delta x and delta y when scrolling (default:1:0)

  For Animations, Scrolling, or Video
  These options influence how long/often and what is shown.
        --loops=<num> : Number of runs through a full cycle. -1 means 'forever'.
                        If not set, videos loop once, animated images forever
                        unless there is more than one file to show.
        --frames=<num>: Only show first num frames (if looping, loop only these)
        --frame-offset=<num>: Start animation/video at this frame
        -t<seconds>   : Stop after this time, independent of --loops or --frames

Examples

timg some-image.jpg                # display a static image
timg -g50x50 some-image.jpg        # display image fitting in box of 50x50 pixel

# Multiple images
timg *.jpg                         # display all *.jpg images
timg --title *.jpg                 # .. show name in title (short option -F)
timg --title="%b (%wx%h)" *.jpg    # show short filename and image size as title
timg --grid=3x2 *.jpg              # arrange in 3 columns, 2 rows in terminal
timg --fit-width --grid=3 *.jpg    # maximize use of column width (short: -W)
timg --grid=3 -t5 *.gif            # Load gifs one by one in grid. Play each for 5sec.

# Putting it all together; making an alias to list images; let's call it ils = 'image ls'
# This prints images two per row with a filename title. Only showing one frame
# so for animated gifs only the first frame is shown statically.
# With hi-res iTerm or Kitty terminals, consider more columns, e.g --grid=4x1
# Put this line in your ~/.bashrc
alias ils='timg --grid=2x1 --upscale=i --center --title --frames=1 '

# ... using this alias on images outputs a useful column view
ils *.jpg *.gif

# Read the list of images to load from a file. One filename per line.
locate "*.jpg" > /tmp/allimg.txt ; timg -f /tmp/allimg.txt

# Show a PDF document, use full width of terminal, trim away empty border
timg -W --auto-crop some-document.pdf
timg --frames=1 some-document.pdf    # Show a PDF, but only first page

# Reading images from a pipe. The filename '-' means 'read from stdin.
# In this example generating a QR code and have timg display it:
qrencode -s1 -m2 "http://timg.sh/" -o- | timg -

# Here, using gnuplot output right in the shell
echo "set terminal png; plot sin(x);" | gnuplot | timg -

# Open an image from a URL. URLs are internally actually handled by the
# video subsystem, so it is treated as a single-frame 'film', nevertheless,
# many image-URLs just work. But some image-specific features, such as trimming
# or scrolling, won't work.
timg --center https://i.kym-cdn.com/photos/images/newsfeed/000/406/282/2b8.jpg

# Sometimes, it is necessary to manually crop a few pixels from an
# uneven border before the auto-crop finds uniform color all-around to remove.
# For example with --auto-crop=7 we'd remove first seven pixels around an image,
# then do the regular auto-cropping.
#
# The following example loads an image from a URL; --auto-crop does not work with
# that, so we have to get the content manually, e.g. with wget. Piping to
# stdin works; in the following example the stdin input is designated with the
# special filename '-'.
#
# For the following image, we need to remove 3 pixels all around before
# auto-crop can take over removing the remaining whitespace successfully:
wget -qO- https://imgs.xkcd.com/comics/a_better_idea.png | timg --auto-crop=3 -

timg multi-resolution.ico   # See all the bitmaps in multi-resolution icons-file
timg --frames=1 multi-resolution.ico  # See only the first bitmap in that file

timg some-video.mp4         # Watch a video.

# Play content of webcam (This assumes video4linux2, but whatever input devices
# are supported on your system with libavdevice-dev)
timg /dev/video0

# If you read a video from a pipe, it is necessary to skip attempting the
# image decode first as this will consume bytes from the pipe. Use -V option.
youtube-dl -q -o- -f'[height<480]' 'https://youtu.be/dQw4w9WgXcQ' | timg -V -

# Show animated gif, possibly limited by timeout, loops or frame-count
timg some-animated.gif      # show an animated gif forever (stop with Ctrl-C)
timg -t5 some-animated.gif                   # show animated gif for 5 seconds
timg --loops=3 some-animated.gif             # Loop animated gif 3 times
timg --frames=3 --loops=1 some-animated.gif  # Show only first three frames
timg --frames=1 some-animated.gif            # Show only first frame. Static image.

# Scroll
timg --scroll some-image.jpg       # scroll a static image as banner (stop with Ctrl-C)
timg --scroll=100 some-image.jpg   # scroll with 100ms delay

# Create a text with the ImageMagick 'convert' tool and send to timg to scroll
convert -size 1000x60 xc:none -fill red -gravity center -pointsize 42 \
        -draw 'text 0,0 "Watchen the blinkenlights..."' -trim png:-   \
      | timg --scroll=20 -

# Scroll direction. Horizontally, vertically; how about diagonally ?
timg --scroll --delta-move=1:0 some-image.jpg  # scroll with dx=1 and dy=0, so horizontally.
timg --scroll --delta-move=-1:0 some-image.jpg # scroll horizontally in reverse direction.
timg --scroll --delta-move=0:2 some-image.jpg  # vertical, two pixels per step.
timg --scroll --delta-move=1:1 some-image.jpg  # diagonal, dx=1, dy=1

# Background color for transparent images (SVG-compatible strings are supported)
# and generally useful if you have a transparent PNG that is otherwise hard
# to see on your terminal background.
timg -b auto some-transparent-image.png  # use terminal background if possible
timg -b none some-transparent-image.png  # Don't use blending
timg -b lightgreen some-transparent-image.png
timg -b 'rgb(0, 255, 0)' some-transparent-image.png
timg -b '#0000ff' some-transparent-image.png

# Checkerboard/Photoshop-like background on transparent images
timg -b lightgray -B darkgray some-transparent-image.png

# .. with adjustable size.
timg -b lightgray -B darkgray --pattern-size=4 some-transparent-image.png
Partially transparent icon on champagne-colored terminal emulator
-b auto -b lightgreen -b lightgreen -B yellow -b none
--pattern-size=1 --pattern-size=4

Include in file browsers

There are many terminal based file-browsers. Adding timg to their configuration is usually straight forward.

# Another use: can run use this in a fzf preview window:
echo some-image.jpg | fzf --preview='timg -E --frames=1 --loops=1 -g $(( $COLUMNS / 2 - 4 ))x$(( $FZF_PREVIEW_LINES * 2 )) {}'

# Use in vifm. ~/.config/vifm/vifmrc
filextype *.avi,*.mp4,*.wmv,*.dat,*.3gp,*.ogv,*.mkv,*.mpg,*.mpeg,*.vob,
         \*.fl[icv],*.m2v,*.mov,*.webm,*.ts,*.mts,*.m4v,*.r[am],*.qt,*.divx,
         \*.as[fx]
        \ {View in timg}
        \ timg --title --center --clear %f,

filextype *.bmp,*.jpg,*.jpeg,*.png,*.gif,*.xpm
        \ {View in timg}
        \ timg --title --center --clear %f; read -n1 -s -r -p "Press any key to return",

Other fun things

# Also, you could store the output and cat later to your terminal...
timg -g80x40 some-image.jpg > /tmp/imageout.txt
cat /tmp/imageout.txt

# Of course, you can redirect the output to somewhere else. I am not suggesting
# that you rickroll some terminal by redirecting timg's output to a /dev/pts/*
# you have access to, but you certainly could...

# Of course, you can go really crazy by storing a cycle of an animation. Use xz
# for compression as it seems to deal with this kind of stuff really well:
timg -g60x30 --loops=10 nyan.gif | xz > /tmp/nyan.term.xz

# ..now, replay the generated ANSI codes on the terminal. Since it would
# rush through as fast as possible, we have to use a trick to wait between
# frames: Each frame has a 'move cursor up' escape sequence that contains
# an upper-case 'A'. We can latch on that to generate a delay between frames:
xzcat /tmp/nyan.term.xz | gawk '/\[.*A/ { system("sleep 0.1"); } { print $0 }'

# You can wrap all that in a loop to get an infinite repeat.
while : ; do xzcat... ; done

# (If you Ctrl-C that loop, you might need to use 'reset' for terminal sanity)

Terminal considerations

This section contains some details that you only might need to ever look at if the output is not as expected.

Many terminals support direct hi-res image output

The Kitty, iTerm2, and wezterm terminals as well as other modern terminals such as Konsole or the terminal in vscode allow to directly display high-resolution pictures.

If timg is running in such a terminal, it will attempt to auto-detect that feature and use that mode. If your terminal does support the feature but can't be auto-detected, you can explicitly choose the pixelation option in question with command line flag or environment variable (see timg --help). (Please file an issue with timg if auto-detect does not work).

VSCode Terminal

The terminal in vscode to display images in high-resolution, you need to enable the Terminal > Integrated: Enable Images setting in vscode. Otherwise you have to explicitly choose -pq to show the 'block' images.

In tmux

The terminal multiplexer tmux prevents high-resolution images as it filters out the escape codes. However, with some ... workarounds, timg can show such pictures in tmux >= version 3.3 iff in a kitty-terminal.

So if you need hi-res pictures in tmux, use a kitty terminal; you also have to explicitly set the pixelation to -pk (see timg --help for details).

Sixel

Other terminals support an older high-resolution sixel-protocol, which you can choose with -ps. Note, for this to work in xterm, you need to invoke it with xterm -ti vt340.

High resolution and low bandwidth

If watching hi-res videos remotely is too slow (due to high bandwidth requirements or simply because your terminal has to do more work), try setting the environment variable TIMG_ALLOW_FRAME_SKIP=1 to allow timg leaving out frames to stay on track (see timg --help, environment variable section). You can also attempt to set the --compress level higher.

Half block and quarter block rendering

Terminals that do not support high-resolution image output can still show images by virtue of showing colored blocks.

The half block pixelation (-p half) uses the the unicode character [▄](U+2584 - 'Lower Half Block') or [▀](U+2580 - 'Upper Half Block') (depending on the TIMG_USE_UPPER_BLOCK environment variable). If the top and bottom color is the same, a simple space with background color is used.

The quarter block pixelation (-p quarter) uses eight different blocks.

With both of these pixelations, choosing the foreground color and background 24-bit color, timg can simulate 'pixels'. With the half-block pixelation, this can assign the correct color to the two 'pixels' available in one character cell, in the quarter pixelation, four 'pixels' have to share two colors, so the color accuracy is slighlty worse but it allows for higher spatial resolution.

The -p command line flag allows to choose between -p half, -p quarter, also possible to just shorten to -ph and -pq. Default is -pq (see above how this looks like).

Terminals that don't support Unicode or 24 bit color will probably not show a very pleasant output. For terminals that only do 8 bit color, use the --color8 command line option.

Half block: Choice of rendering block

By default, timg uses the 'lower half block' to show the pixels in -p half mode. Depending on the font the terminal is using, using the upper block might look better, so it is possible to change the default with an environment variable. Play around with this value if the output looks poor on your terminal. I found that on my system there is no difference for konsole or xterm but the cool-retro-term looks better with the lower block, this is why it is the default.

In some terminals, such as alacritty (and only with certain font sizes), there seems to be the opposite working better. To change, set this environment variable:

export TIMG_USE_UPPER_BLOCK=1   # change default to use upper block.

(this only will work fully with -p half. In -p quarter mode, there are additional blocks that can't be worked around)

What a problematic choice of block looks like

The image generally looks a bit 'glitchy' if the terminal leaves little space between blocks, so that the wrong background color shows on a single line between pixels. This is likely not intended by the terminal emulator and possibly happening on rounding issues of font height or similar.

Anyway, we can work around it (fully in -p half, partially in -p quarter mode). In the following illustration you see how that looks like. If you see that, change the TIMG_USE_UPPER_BLOCK environment variable.

Glitchy. Change TIMG_USE_UPPER_BLOCK Looks good

Other artifacts

Some terminals leave one pixel of horizontal space between characters that result in fine vertical lines in the image. That can't be worked around, send a bug or better pull request to your terminal emulator.

Wrong font aspect ratio

Usually, timg attempts to determine the font aspect ratio and apply some correction if it is off from the nominal 1:2. But if you notice that the image displayed is not quite the right aspect ratio because of the terminals font used, you can set an environment variable TIMG_FONT_WIDTH_CORRECT with a factor to make it look correctly.

Increasing the visual width by 10% would be setting the value to 1.1 for instance.

export TIMG_FONT_WIDTH_CORRECT=1.1
timg myimage.jpg

This is an environment variable, so that you can set it once to best fit your terminal emulator of choice and don't have to worry about later.

Example
Terminal font too narrow Correct. Here with TIMG_FONT_WIDTH_CORRECT=1.375

Installation

Install pre-built package

Packaging status

Debian-based systems

sudo apt install timg

NixOS or Nix package manager

nix-env -i timg

macOS

brew install timg

Use AppImage

The timg release page also has a minimal binary in the AppImage package format. To keep the size small, it does not include video decoding or some more fancy image formats. It is good for many contexts or if you want to try out timg, but for a full-featured binary, use one from your distribution or build from source.

Build and Install from source

Get dependencies on Debian/Ubuntu

sudo apt install cmake git g++ pkg-config
sudo apt install libgraphicsmagick++-dev libturbojpeg-dev libexif-dev libswscale-dev libdeflate-dev librsvg2-dev libcairo-dev # needed libs

# For sixel output.
sudo apt install libsixel-dev

# If you want to include video decoding, also install these additional libraries
sudo apt install libavcodec-dev libavformat-dev

sudo apt install libavdevice-dev # If you want to read from video devices such as v4l2

sudo apt install libopenslide-dev # If you want to add OpenSlide images support
sudo apt install libpoppler-glib-dev  # if WITH_POPPLER enabled.

sudo apt install pandoc  # If you want to recreate the man page

Get dependencies on NixOS or Nix package manager

The dependencies are set-up in the shell.nix, so you're ready to go opening a nix shell

nix-shell

Get dependencies on Fedora

sudo dnf install cmake git g++ pkg-config
sudo dnf install GraphicsMagick-c++-devel turbojpeg-devel libexif-devel libswscale-free-devel librsvg2-devel cairo-devel libdeflate-devel poppler-glib-devel libsixel-devel qoi-devel

# If you want to include video decoding, also install these additional libraries
sudo dnf install libavcodec-free-devel libavformat-free-devel libavdevice-free-devel openslide-devel

sudo dnf install pandoc  # If you want to recreate the man page

Get dependencies on macOS

# Homebrew needs to be available to install required dependencies
brew install cmake git GraphicsMagick webp jpeg-turbo libexif librsvg cairo  # needed libs

# If you want to include video decoding, install these additional libraries
brew install ffmpeg

# If you want to add OpenSlide images support
brew install openslide

brew install pandoc  # If you want to recreate the man page

Get repo and compile timg

In the script below you see that the build system allows for some compile-time choices:

  • WITH_LIBSIXEL Use libsixel to output images in sixel graphics format. Default ON.
  • WITH_VIDEO_DECODING allow for video decoding. Requires ffmpeg-related libraries. You typically want this ON (default)
    • WITH_VIDEO_DEVICE this allows for accessing connected video devices, e.g. you can watch your webcam input (requires WITH_VIDEO_DECODING).
  • WITH_GRAPHICSMAGICK This is the main image loading library so you typically want this ON (default).
  • WITH_TURBOJPEG If enabled, uses this for faster jpeg file loading. You typically want this ON (default).
  • WITH_POPPLER High-quality and faster PDF renderer. Needs poppler and cairo. If not compiled-in, will fallback to GraphicsMagick, but that typically results in lower quality renderings. Typically want this ON (default).
  • WITH_RSVG High-quality SVG renderer. Needs librsvg and cairo. If not compiled-in, will fallback to GraphicsMagick, but that typically results in lower quality renderings. Typically want this ON (default).
  • WITH_OPENSLIDE_SUPPORT Openslide is an image format used in scientific applications. Rarely used, so default off, switch ON if needed.
  • WITH_QOI_IMAGE Allow decoding of Quite Ok Image format QOI. Small and simple, default ON.
  • WITH_STB_IMAGE Compile the simpler STB image library directly into the timg binary in cases where Graphicsmagick is not suitable for dependency pruning reasons; output can be slower and of less quality. It is default ON (default) but will always only attempted after other image loading fails. Turn off if you can use GraphicsMagick and want to reduce potential security vectors.

You can choose these options by providing -D<option>=ON on the cmake command line, see below.

git clone https://github.com/hzeller/timg.git  # Get repo
cd timg                     # Enter the checked out repository directory.
mkdir build                 # Generate a dedicated build directory.
cd build
# cmake with your desired options, see descriptions above
cmake ../ -DWITH_OPENSLIDE_SUPPORT=On
make

# After compilation, you can run from build/src/timg or install on your system with
sudo make install