L8 script

L8.sh

#!/bin/bash

echo "Enter bands (ie 4 3 2)"

read B1 B2 B3

echo "Enter the resulting filename"

read outputname

#unzip all files in directory
for filename in *.tar
do
  tar zxf $filename
done

filename=$B1$B2$B3

#project each band epsg 3857, which is web mercator
for BAND in $B1 $B2 $B3; do
  gdalwarp -t_srs EPSG:3857 *$BAND.TIF $BAND-projected.tif;
done

mkdir results

for BAND in $B1 $B2 $B3; do
mv $BAND-projected.tif results
done

cd results

#combine the bands in one image
convert $B1-projected.tif $B2-projected.tif $B3-projected.tif -combine $filename.tif

#adjust the colors in two step process
convert -sigmoidal-contrast 50x15% $filename.tif $filename-adj.tif

convert -channel B -gamma 1.25 -channel G -gamma 1.25 \
-channel RGB -sigmoidal-contrast 25x25% $filename.tif $filename-corrected.tif

#convert to 8 bit for tile mill rendering
convert -depth 8 $filename-corrected.tif $filename-corrected-8bit.tif

#create a geo reference file
listgeo -tfw $B3-projected.tif

#rename the file to match our created image
mv $B3-projected.tfw $filename-corrected-8bit.tfw

#srs, rename
gdal_edit.py -a_srs EPSG:3857 $filename-corrected-8bit.tif
mv $filename-corrected-8bit.tif $outputname-projected.tif

Nice!