moarsaic-v1

#!/bin/bash
#
# GTFO license:
# this program is provided with NO GUARANTEE and NO SUPPORT
# if it breaks or does not do what you want, FIX IT YOURSELF
#
# a script for building a screen-size tile-mosaic-thingy out of the 16 colours extracted from an image.
# tile-divisor is args[2], so you can decide the size of the tiles, somewhat.
# by rhowaldt
#
# depends: xdpyinfo, imagemagick

#FUNCTIONS AND SHIT

# SHUFFLE FUNCTION based on Knufth-Fisher-Yayes shuffle algorithm
# http://mywiki.wooledge.org/BashFAQ/026 thank you!
# takes an array[@] as input through 'shuffle ARRAY[@]', outputs arr[@]
shuffle() {
   local i tmp size max rand
   arr=("${!1}") # retrieve array from $1
   # $RANDOM % (i+1) is biased because of the limited range of $RANDOM
   # Compensate by using a range which is a multiple of the array size.
   size=${#arr[*]}
   max=$(( 1600 / size * size ))

   for ((i=size-1; i>0; i--)); do
      while (( (rand=$RANDOM) >= max )); do :; done
      rand=$(( rand % (i+1) ))
      tmp=${arr[i]} arr[i]=${arr[rand]} arr[rand]=$tmp
   done
}

#VARIABLES AND SUCH
if [[ $# -ne 2 ]]; then
   echo
   echo "Your arguments are wrong."
   echo "Usage: moarsaic [image] [divisor (integer)]"
   exit 1
fi

IMAGE="$1"
DIVISOR=$2
x="x" #this is pathetic, but who cares?
MAXTILES=1000 # the amount of tiles needed to receive a prompt
COLAMOUNT=16

# TODO: create flags for
# --cols [NUM] # amount of colours to grab from original
# --resize # resize image before processing (faster)
# --view # open resulting image in feh
# --compare # open original + resulting image in feh side-by-side
# --output # filename
# --filter # send output through filter (separate script)


#THE WORKINGS
echo
echo "* * * * * M O A R S A I C * * * * *"
echo

# 1. wanna know how many tiles
read RES_X RES_Y <<<$(xdpyinfo | grep dimensions | awk '{print $2}' | awk -Fx '{print $1, $2}') # determine screen resolution: thanksss http://superuser.com/questions/418699

SMALLEST=$(( RES_X < RES_Y ? RES_X : RES_Y )) #find the smallest side
if [[ $SMALLEST -eq $RES_X ]]; then
   TILESIZE_X=$(( SMALLEST/DIVISOR )) #make sure still X=X
   TILESIZE_Y=$TILESIZE_X # make them square
else [[ $SMALLEST -eq $RES_Y ]]
   TILESIZE_Y=$(( SMALLEST/DIVISOR ))
   TILESIZE_X=$TILESIZE_Y
fi
TILES_X=$(( ( RES_X/TILESIZE_X ) + 1 )) #the amount of tiles along one side will always be 1 greater than the amount that fits - for now
TILES_Y=$(( ( RES_Y/TILESIZE_Y ) + 1 )) #because what happens when it fits exactly...
TILES=$(( TILES_X * TILES_Y ))

echo
echo "Image: $1"
echo "Screen Resolution: $RES_X$x$RES_Y"
echo "Tilesize: $TILESIZE_X$x$TILESIZE_Y"
echo "Tiles: $TILES ($TILES_X$x$TILES_Y)"
echo

# make sure you really want to hang your terminal
if [ "$TILES" -ge "$MAXTILES" ]
then
    while true; do
        read -p "Mate, this will create $TILES tiles. That's quite a lot. Proceed? " yn
        case $yn in
            [Yy]* ) echo "Splendid Superninja, let'ssssssss do it!"; echo; break;;
            [Nn]* ) echo "Baibai."; exit;;
            * ) echo "Answer yes or no. It's not that difficult. Let's try again."; echo;;
        esac
    done
fi

# 2. create a 16 colour palette from the temporary image

# resize the image to save loads on speed with wallpapers etc
convert "$IMAGE" -resize 800 tmp_image.png
# comment this out if you just want to use the full image without downsizing.
# downsizing reduces the number of pixels and thus induces a loss of colours
# this is easiest seen when comparing between different resizings, and noting the vibrancy of colours
#IMAGE=tmp_image.png

echo "Creating colour palette..."
PALETTE=$(convert "$IMAGE" -colors $COLAMOUNT -format "%c" histogram:info:)
rm tmp_image.png
HEXLIST=$(echo "$PALETTE" | sed 's/^.*\#\(.*\) srgb.*/\1/g') #grab just the numbers
COL=("0" "8" "1" "9" "2" "A" "3" "B" "4" "C" "5" "D" "6" "E" "7" "F"); #these numbers need to be added to the front of the previous
q=0

declare -a COLOURS

while read line; do
      COLOURS=("${COLOURS[@]}" "$line"); #concatenate the shit.
      let q=q+1
done <<< "$HEXLIST"

# 3. get enough colours to fill all the tiles
# pick randomly from the 16-colour list, removing each pick until none are left. repeat until all tiles are filled.
declare -a COLOURTILES
while [[ ${#COLOURTILES[@]} -lt $TILES ]] #check whether we are at $TILES yet.
do
   for index in `shuf --input-range=0-$(( ${#COLOURS[*]} - 1 )) | head -${TILES}`
    do
        COLOURTILES=("${COLOURTILES[@]}" "${COLOURS[$index]}")
    done
done

# 4. build a tile-mosaic-thingy out of the colours
echo "Grab the lube in eager anticipation. Placing colours..."
echo

# convert into imagemagick xc-tags (xc:#222222) and arrange in grid through append+/-
COLLINE="(" # the line with the colour setup
xcount=1
ycount=1
for (( i=0; i<${#COLOURTILES[@]}; i++ ))
do
    # echo "ycount: $ycount - xcount: $xcount" #debug for correct iteration
    if [ $ycount -lt $TILES_Y ]
    then
        if [ $xcount -lt $TILES_X ]
            then
            COLLINE+=" xc:#${COLOURTILES[i]}"
            xcount=$((xcount + 1))
        else
            COLLINE+=" xc:#${COLOURTILES[i]} +append ) -append ("
            xcount=1
            ycount=$((ycount + 1))
        fi

    else # final row, final column

        if [ $xcount -lt $TILES_X ]
            then
            COLLINE+=" xc:#${COLOURTILES[i]}"
            xcount=$((xcount + 1))
        else # final colour
            COLLINE+=" xc:#${COLOURTILES[i]} +append ) -append"
            break
        fi
    fi
done

# echo "$COLLINE" # debug for correct imagemagick syntax

convert $COLLINE -filter point -resize "$RES_X$x$RES_Y"\! moarsaic-result.jpg

# (temp) feh for viewing the result
feh -m -H 410 -W 800 -E 400 -y 400 $1 moarsaic-result.jpg

echo "C'est fini."
exit