How to preview images

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Starting with 0.8 vifm provides four macros describing preview area that can be used along with external applications to preview images in a terminal, they are:

  • %px x coordinate of top-left corner of preview area;
  • %py y coordinate of top-left corner of preview area;
  • %pw width of preview area;
  • %ph height of preview area.

Below is a description and an example.

Prerequisites[edit]

1. w3mimgdisplay which might be part of w3m package or a separate one.

2. Terminal emulator without double buffering, otherwise w3m will fail to display images properly.

Setup[edit]

1. Create script that invokes w3m. w3mimgdisplay executable might reside in different locations depending on the distribution. Below is a sample script, which can be used after correcting several parameters at the top.

#!/bin/bash
#
# Based on script by z3bra -- 2014-01-21
 
W3MIMGDISPLAY="/usr/libexec/w3m/w3mimgdisplay"
FONTH=15 # Size of one terminal row
FONTW=7 # Size of one terminal column
 
X=$1
Y=$2
COLUMNS=$3
LINES=$4
FILENAME=$5
 
read width height <<< `echo "5;$FILENAME" | $W3MIMGDISPLAY`
if [ -z "$width" -o -z "$height" ]; then
    echo 'Error: Failed to obtain image size.'
    exit 1
fi
 
x=$((FONTW * X))
y=$((FONTH * Y))
 
max_width=$((FONTW * COLUMNS))
max_height=$((FONTH * LINES))
 
if [ "$width" -gt "$max_width" ]; then
    height=$((height * max_width / width))
    width=$max_width
fi
if [ "$height" -gt "$max_height" ]; then
    width=$((width * max_height / height))
    height=$max_height
fi
 
w3m_command="0;1;$x;$y;$width;$height;;;;;$FILENAME\n4;\n3;"
 
echo -e "$w3m_command" | $W3MIMGDISPLAY

2. Update vifmrc with preview command like the following:

fileviewer *.bmp,*.jpg,*.jpeg,*.png,*.gif,*.xpm
         \ imgt %px %py %pw %ph %c

Replace "imgt" with path to preview script or just update name if script is available in your $PATH (which is the case if you put it under ~/.vifm/scripts).

Notes[edit]

State of terminal support[edit]

One should be aware that this is kinda hack as terminals weren't made to display pictures, thus there might be some difficulties (like double buffering or incomplete clearing). That said, it does work in sufficient amount of configurations.

Positioning[edit]

When running inside terminal emulators, coordinates known to applications are relative to pane/window position. This should be taken into account, because without applying proper offsets images may appear in unexpected locations.

Clearing[edit]

Depending on your terminal this may be enough or require additional script for clearing image leftovers (below), development version of vifm and changed :fileviewer command like this:

fileviewer *.bmp,*.jpg,*.jpeg,*.png,*.gif,*.xpm
         \ imgt %px %py %pw %ph %c
         \ %pc
         \ imgc %px %py %pw %ph

Where imgc is a script that clears background of the terminal (it's configuration is at the top):

#!/bin/bash
 
W3MIMGDISPLAY="/usr/libexec/w3m/w3mimgdisplay"
FONTH=15 # Size of one terminal row
FONTW=7 # Size of one terminal column
 
X=$1
Y=$2
COLUMNS=$3
LINES=$4
 
x=$((FONTW * X))
y=$((FONTH * Y))
 
erase="6;$x;$y;$(( FONTW*COLUMNS ));$(( FONTH*LINES ))\n3;"
echo -e "$erase" | $W3MIMGDISPLAY

This is the case at least for urxvt.

See also[edit]