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diff --git a/bin/crossfade_cat.sh b/bin/crossfade_cat.sh
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+#!/bin/bash
+#
+# crossfade_cat.sh
+#
+# Concatenates two files together with a crossfade of $1 seconds.
+# Filenames are specified as $2 and $3.
+#
+# $4 is optional and specifies if a fadeout should be performed on
+# first file.
+# $5 is optional and specifies if a fadein should be performed on
+# second file.
+#
+# Example: crossfade_cat.sh 10 infile1.wav infile2.wav auto auto
+#
+# By default, the script attempts to guess if the audio files
+# already have a fadein/out on them or if they just have really
+# low volumes that won't cause clipping when mixxing.  If this
+# is not detected then the script will perform a fade in/out to
+# prevent clipping.
+#
+# The user may specify "yes" or "no" to force the fade in/out
+# to occur.  They can also specify "auto" which is the default.
+#
+# Crossfaded file is created as "mix.wav".
+#
+# Original script from Kester Clegg.  Mods by Chris Bagwell to show
+# more examples of sox features.
+#
+
+SOX=sox
+SOXI=soxi
+
+if [ "$3" == "" ]; then
+    echo "Usage: $0 crossfade_seconds first_file second_file [ fadeout ] [ fadein ]"
+    echo
+    echo "If a fadeout or fadein is not desired then specify \"no\" for that option.  \"yes\" will force a fade and \"auto\" will try to detect if a fade should occur."
+    echo
+    echo "Example: $0 10 infile1.wav infile2.wav auto auto"
+    exit 1
+fi
+
+fade_length=$1
+first_file=$2
+second_file=$3
+
+fade_first="auto"
+if [ "$4" != "" ]; then
+    fade_first=$4
+fi
+
+fade_second="auto"
+if [ "$5" != "" ]; then
+    fade_second=$5
+fi
+
+fade_first_opts=
+if [ "$fade_first" != "no" ]; then
+    fade_first_opts="fade t 0 0:0:$fade_length 0:0:$fade_length"
+fi
+
+fade_second_opts=
+if [ "$fade_second" != "no" ]; then
+    fade_second_opts="fade t 0:0:$fade_length"
+fi
+
+echo "crossfade and concatenate files"
+echo
+echo  "Finding length of $first_file..."
+first_length=`$SOX "$first_file" 2>&1 -n stat | grep Length | cut -d : -f 2 | cut -f 1`
+echo "Length is $first_length seconds"
+
+trim_length=`echo "$first_length - $fade_length" | bc`
+
+# Get crossfade section from first file and optionally do the fade out
+echo "Obtaining $fade_length seconds of fade out portion from $first_file..."
+$SOX "$first_file" -e signed-integer -b 16 fadeout1.wav trim $trim_length
+
+# When user specifies "auto" try to guess if a fadeout is needed.
+# "RMS amplitude" from the stat effect is effectively an average
+# value of samples for the whole fade length file.  If it seems
+# quite then assume a fadeout has already been done.  An RMS value
+# of 0.1 was just obtained from trail and error.
+if [ "$fade_first" == "auto" ]; then
+    RMS=`$SOX fadeout1.wav 2>&1 -n stat | grep RMS | grep amplitude | cut -d : -f 2 | cut -f 1`
+    should_fade=`echo "$RMS > 0.1" | bc`
+    if [ $should_fade == 0 ]; then
+        echo "Auto mode decided not to fadeout with RMS of $RMS"
+        fade_first_opts=""
+    else
+        echo "Auto mode will fadeout"
+    fi
+fi
+
+$SOX fadeout1.wav fadeout2.wav $fade_first_opts
+
+# Get the crossfade section from the second file and optionally do the fade in
+echo "Obtaining $fade_length seconds of fade in portion from $second_file..."
+$SOX "$second_file" -e signed-integer -b 16 fadein1.wav trim 0 $fade_length
+
+# For auto, do similar thing as for fadeout.
+if [ "$fade_second" == "auto" ]; then
+    RMS=`$SOX fadein1.wav 2>&1 -n stat | grep RMS | grep amplitude | cut -d : -f 2 | cut -f 1`
+    should_fade=`echo "$RMS > 0.1" | bc`
+    if [ $should_fade == 0 ]; then
+        echo "Auto mode decided not to fadein with RMS of $RMS"
+        fade_second_opts=""
+    else
+        echo "Auto mode will fadein"
+    fi
+fi
+
+$SOX fadein1.wav fadein2.wav $fade_second_opts
+
+# Mix the crossfade files together at full volume
+echo "Crossfading..."
+$SOX -m -v 1.0 fadeout2.wav -v 1.0 fadein2.wav crossfade.wav
+
+echo "Trimming off crossfade sections from original files..."
+
+$SOX "$first_file" -e signed-integer -b 16 song1.wav trim 0 $trim_length
+$SOX "$second_file" -e signed-integer -b 16 song2.wav trim $fade_length
+$SOX song1.wav crossfade.wav song2.wav mix.wav
+
+echo -e "Removing temporary files...\n" 
+rm fadeout1.wav fadeout2.wav fadein1.wav fadein2.wav crossfade.wav song1.wav song2.wav
+mins=`echo "$trim_length / 60" | bc`
+secs=`echo "$trim_length % 60" | bc`
+echo "The crossfade in mix.wav occurs at around $mins mins $secs secs"
+