record-gif.sh

#!/bin/bash

# FILE: record-gif.sh
# DEPS: sudo apt install byzanz gifsicle
# SOURCE: http://askubuntu.com/questions/107726/how-to-create-animated-gif-images-of-a-screencast

# delay in seconds before recording (defaults to 2s).
DELAY=2

# duration in seconds of recording (defaults to 10s).
if [ $# -gt 0 ]; then
    D="--duration=$@"
else
    D="--duration=10"
fi

# output file base name (defaults to "recorded.gif" in current dir).
F="$PWD/recorded"

# use mouse cursor to retrieve window bounds.
XWININFO=$(xwininfo)
read X <<< $(awk -F: '/Absolute upper-left X/{print $2}' <<< "$XWININFO")
read Y <<< $(awk -F: '/Absolute upper-left Y/{print $2}' <<< "$XWININFO")
read W <<< $(awk -F: '/Width/{print $2}' <<< "$XWININFO")
read H <<< $(awk -F: '/Height/{print $2}' <<< "$XWININFO")

# start pre-recording delay.
echo Delaying $DELAY seconds. After that, byzanz will start
for (( i=$DELAY; i>0; --i )) ; do
    echo $i
    sleep 1
done

# start recording and save recorded gif.
byzanz-record --verbose --delay=0 --x=$X --y=$Y --width=$W --height=$H $D $F.gif

# optimize recorded gif.
gifsicle -O $F.gif -o $F.opt.gif