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@swarminglogic
Last active June 5, 2018 20:22
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gifcapture -- A linux tool to record a region of the screen and convert it to a well optimized gif.
#!/bin/bash
delay=0.2
title='default'
count=0
loop=1 #0 for infinite loop
# Set if you want to skip mouse selection
if [[ $# -eq 6 ]]
then
xpos=$3
ypos=$4
xsize=$5
ysize=$6
fi
if [[ $# -eq 0 ]]
then echo "./gifcapture TITLE [OUTPUTDIR] [xpos ypos xsize ysize]"
exit
fi
if [[ $# -ge 1 ]] ; then title=$1 ; fi
if [[ $# -ge 2 ]] ; then outdir=$2 ; fi
outdir=$title
if [[ ! -n $xsize || ! -n $ysize || ! -n $xpos || ! -n $ypos ]]
then
if [ ! `which xdotool` ] ; then echo "You need xdotool!" && exit ; fi
echo -n "Move mouse cursor to TOP LEFT of region. Press enter";
read -n 1
eval $(xdotool getmouselocation --shell 2>/dev/null)
xpos=$X;
ypos=$Y;
echo -n "Move mouse cursor to BOTTOM RIGHT of region. Press enter";
read -n 1
eval $(xdotool getmouselocation --shell 2>/dev/null)
xsize=$(($X-$xpos))
ysize=$(($Y-$ypos))
fi
if [[ $xsize -le 0 || $ysize -le 0 ]] ; then echo "Bad region" && exit; fi
echo "Input:
----------------------------------------
xpos=$xpos
ypos=$ypos
xsize=$xsize
ysize=$ysize"
echo -n "Press enter to start recording. CTRL-C to end recoding.";
read -n 1
if [ ! -e $outdir ]
then
mkdir $outdir
fi
finalizeGif ()
{
# Remove potentially broken temporary file due to interrupt
badfile=`find ./$outdir -name "*.png~"|head -n1`
rm -f $badfile
rm -f `sed 's/~//g' <<< $badfile`
# Specify delay in tics for gif delay
delayInTics=`bc <<< "$delay * 100"`
# N Colors in gif optimization
ncolors=256
# Old way of creating an unoptimized gif. This creates poor results!
# echo -n "Converting to animated gif: "
# convert -delay 20 -loop 0 -trim $outdir/*.png $outdir/$title.gif
# echo "... Done: $outdir/$title.gif";
# Good way
echo -n "Creating optimized animated gif: "
# Determine cpu cores
nCores=`cat /proc/cpuinfo | grep cores | head -n 1 | sed 's/.*:\s//g'`
# Temporarily converts pngs to gifs, with good quantization.
# Operation is quite CPU intensive and is therefore parallelized
mkdir $outdir/tmp
(cd $outdir && find . -name "*.png" -print0 | xargs -0 -n 1 -P $(($nCores + 1)) sh \
-c 'nice convert $1 +dither -colors '$ncolors' ./tmp/$1.gif ' sh)
# Creating the optimized gif. Also ignores color variations that are less than 9%
convert -delay $delayInTics $outdir/tmp/*.gif -loop $loop -layers Optimize \
-fuzz 9% $outdir/$title.opt.gif
rm -rf tmp
echo "... Done: $outdir/$title.opt.gif";
exit 0
}
trap finalizeGif SIGINT SIGTERM
while true
do
((count++))
numtext=`printf '%.3d' $count`
nice import -window root -crop ${xsize}x${ysize}+${xpos}+${ypos} -quality 100 $outdir/${numtext}_${title}_${delay}.png
nice mogrify -strip $outdir/${numtext}_${title}_${delay}.png
sleep $delay
done
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