An easy (ha!) way to resize and png optimize screenshots in OSX. This is good for resampling and then optimizing retina screenshots when sending to people. It dumps things into Dropbox/public/Screenshots, and copies the public URL to the clipboard. Bind it to a hot key to to make it easy to use. Check out the output: https://dl.dropboxuserconten…

gistfile1.txt

#!/bin/bash

# *******************************
# Instructions on turning this into an OSX service:
#    http://blog.lanceli.com/2012/08/downscale-screenshot-at-hight-resolution-on-retina-mackbook-pro.html
# *******************************


# the path where screenshots to save
DROPBOX_ID= ENTER YOUR DROPBOX ID HERE
SS_PATH="/Users/$(whoami)/Dropbox/Public/Screenshots"

if [ ! -e $SS_PATH ]
then
    mkdir  -p $SS_PATH
fi

# if you want to save them to your desktop, SS_PATH should be "/Users/YOURNAME/Desktop"

# a variable of unix timestamp for screenshot file name
NOW=$(date +%s)
OUT=$(mktemp /tmp/XXXXX)

PNGQUANT='/Applications/ImageAlpha.app/Contents/Resources/pngquant'

# execute screen capture command, screenshot$NOW.png is the name of file
screencapture -t png -i $OUT

# check the DPI, if it is 2x res (144dpi), then reduce it... 
DPI=$(sips -g dpiWidth $OUT | tail -1 | awk '{print $2/1}')
echo $DPI

if [ $DPI -eq 144 ]
then 
	WIDTH=$(sips -g pixelWidth $OUT | awk '/pixelWidth/ {print $2/2}')
    
    TMP=$(mktemp /tmp/XXXXX)
	sips --resampleWidth $WIDTH $OUT --out $TMP
    rm $OUT
    mv $TMP $OUT
fi

if [ -e $PNGQUANT ]
then
    TMP=$(mktemp /tmp/XXXXX)
    cat $OUT | $PNGQUANT - > $TMP
    rm $OUT
    mv $TMP $SS_PATH/$(basename $OUT).png
else
    mv $OUT $SS_PATH/$(basename $OUT).png
fi

# copy that 
echo "https://dl.dropboxusercontent.com/u/$DROPBOX_ID/Screenshots/$(basename $OUT).png" | pbcopy