For the final variation I wanted to explore the linear progression of the video. That is, up till now all of the variations have jumped randomly between different parts of the video. A skipping CD will always attempt to play from start to finish, even if it does skip occasionally. So, for this variation I wrote a script that created sequenced segments of varying lenghts (between 0.1-0.99 seconds) and then repeats them up to six times.

Observations

This variation, like the last one, resembles a skipping CD. By sequencing the samples I’ve lost some of the unpredictable, YTP-style edits but have gained more clarity. It has also been pointed out (thanks Rosa!) that a skipping CD doesn’t always skip. There may be periods of it working followed by glitches/skipping.

#Usage: ./movie_cut.sh /path/to/file.avi Clip-duration-in-seconds
#e.g. ./movie_cut.sh 4.01

#start position
startPos=0

filenumber=$(printf "%05d")
while [ $filenumber -le 50 ]
do

#define random integer
rand=$RANDOM

#define random duration (up to 0.999 seconds)
duration=$(echo "0.$rand") 

#get path of file
path=$( readlink -f "$( dirname "$1" )" )

#get filename minus extension
file=$(basename "$1")
filename="${file%.*}"

#cut the video
avconv -i $1 -ss $startPos -t $duration -qscale 0 -ab 384k -y "$path"/"$filenumber"_"$filename"_cut.avi

filenumber=`expr $filenumber + 1`
filenumber=$(printf "%05d" $filenumber)

#increment the start position of the next video by the duration of the previous video
startPos=$(echo "scale = 2; $startPos + $(echo "0.$rand")" | bc | sed -e s/^/0/)

done

The following script was then run on the output files from the previous script. It creates numbered diplicates of the source files.

#!/bin/bash

for file in *.avi
do

#number of times to duplicate the file (between 1 and 6)
max=$(shuf -i 1-6 -n 1)

number=1
while [ $number -le $max ]
do

#get path of file
path=$( readlink -f "$( dirname "$file" )" )

#get filename minus extension
file=$(basename "$file")
filename="${file%.*}"

#get extension
extension="${file##*.}"

#copy the file to a new file
cp $file "$path"/"$filename"_"$number".$extension

number=`expr $number + 1`

done

done

For the third variation I began to explore rhythm further by repeating the random segments a number of times. I used the script from Variation #2 – although I only created 20 segments – and then repeated these between two and six times each.

Observations

This variation bears more resemblance to a skipping CD than the previous two. The possibility of this being performed by live musicians becomes impossible due to the very short length of some of the segments.

Code

This script requires libav to run and has been tested on Ubuntu 13.04.

#!/bin/bash
#Usage: ./movie_cut.sh /path/to/file.avi
#e.g. ./movie_cut.sh video.avi

filenumber=$(printf "%05d")
while [ $filenumber -le 20 ]
do

#calculate the length of the video
length=`expr $(avprobe -loglevel error -show_streams $1 | grep duration | cut -f 2 -d = | head -1 | cut -d "." -f 1) \* 100`
 
#start position
startPos=$(echo "scale=2;$(shuf -i 1-$length -n 1) / 100" | bc | sed -e s/^/0/)

#define random duration (up to 0.999 seconds)
duration=$(echo "0.$RANDOM")

#get path of file
path=$( readlink -f "$( dirname "$1" )" )

#get filename minus extension
file=$(basename "$1")
filename="${file%.*}"

#cut the video
avconv -i $1 -ss $startPos -t $duration -qscale 0 -ab 384k -y "$path"/"$filenumber"_"$filename"_cut.avi

filenumber=`expr $filenumber + 1`
filenumber=$(printf "%05d" $filenumber)

done

The following script was then run on the output files from the previous script. It creates numbered duplicates of the source files.

#!/bin/bash

for file in *.avi
do

#number of times to duplicate the file (between 1 and 6)
max=$(shuf -i 1-6 -n 1)

number=1
while [ $number -le $max ]
do

#get path of file
path=$( readlink -f "$( dirname "$file" )" )

#get filename minus extension
file=$(basename "$file")
filename="${file%.*}"

#get extension
extension="${file##*.}"

#copy the file to a new file
cp $file "$path"/"$filename"_"$number".$extension

number=`expr $number + 1`

done

done

For the second and subsequent variations I used only seven instances of the chorus line as a source. For this variation I then wrote a script on each of the seven videos that created 90 segments of varying lengths (up to 0.999 seconds) from random positions in the video. I then finally composed them into one video.

Observations

With a shorter source input, this variation is more rhythmic than the first. There are more instances of the audio resembling a stuttering CD, though still lots of instances where it jumps around erratically.

Code

This script requires libav to run and has been tested on Ubuntu 13.04.

#!/bin/bash
#Usage: ./movie_cut.sh /path/to/file.avi
#e.g. ./movie_cut.sh video.avi

filenumber=$(printf "%05d")
while [ $filenumber -le 90 ]
do

#calculate the length of the video
length=`expr $(avprobe -loglevel error -show_streams $1 | grep duration | cut -f 2 -d = | head -1 | cut -d "." -f 1) \* 100`
 
#start position
startPos=$(echo "scale=2;$(shuf -i 1-$length -n 1) / 100" | bc | sed -e s/^/0/)

#define random duration (up to 0.999 seconds)
duration=$(echo "0.$RANDOM")

#get path of file
path=$( readlink -f "$( dirname "$1" )" )

#get filename minus extension
file=$(basename "$1")
filename="${file%.*}"

#cut the video
avconv -i $1 -ss $startPos -t $duration -qscale 0 -ab 384k -y "$path"/"$filename"_"$filenumber"_cut.avi

filenumber=`expr $filenumber + 1`
filenumber=$(printf "%05d" $filenumber)

done

For the first variation I used the video of the entire performance – minus the introduction from Don Cornelius and the fade out – as input. I then wrote a script that created 600 segments of varying lengths (up to 0.999 seconds) from random positions in the video and finally composed them into one video.

Observations

This variation is perhaps too chaotic to be considered a reproduction of the aesthetics of a skipping CD. The individual segments jump from extreme ends of the video too quickly to be recognisable, which bears little resemblance to skipping CDs or broken video files, which often repeat segments at the point at which they encounter an error.

Code

This script requires libav to run and has been tested on Ubuntu 13.04.

#!/bin/bash
#Usage: ./movie_cut.sh /path/to/file.avi
#e.g. ./movie_cut.sh video.avi

filenumber=$(printf "%05d")	
while [ $filenumber -le 600 ]
do

#calculate the length of the video
length=`expr $(avprobe -loglevel error -show_streams $1 | grep duration | cut -f 2 -d = | head -1 | cut -d "." -f 1) \* 100`
 
#start position
startPos=$(echo "scale=2;$(shuf -i 1-$length -n 1) / 100" | bc | sed -e s/^/0/)

#define random duration (up to 0.999 seconds)
duration=$(echo "0.$RANDOM")

#get path of file
path=$( readlink -f "$( dirname "$1" )" )

#get filename minus extension
file=$(basename "$1")
filename="${file%.*}"

#cut the video
avconv -i $1 -ss $startPos -t $duration -qscale 0 -ab 384k -y "$path"/"$filenumber"_"$filename"_cut.avi

filenumber=`expr $filenumber + 1`
filenumber=$(printf "%05d" $filenumber)

done