dubstep-data

The programs I wrote for the Encoding data in dubstep drops blog post: https://blog.benjojo.co.uk/post/encoding-data-into-dubstep-drops

Note this does not work on Windows machines at this point in time

Packages Required

• SoX (Sound Exchange) - Convert various formats of computer audio files to other formats. Also applies various effects to these sound files
  • sudo apt-get install sox
• Google Golang - Google's Go Language
  • sudo apt-get install golang
  • Note: You will need to set the GOPATH
• FFMPEG - Decode, encode, filter and play files
  • sudo apt-get install ffmpeg

How to run

• Note: If you have not set your GOPATH correctly, it will not be able to perform the go get commmands

Acquire repos:

go get github.com/dgryski/go-bitstream
go get github.com/benjojo/dubstep-data

Once they have downloaded, navigate to the 'github.com' folder. By default it can be found through the home/ directory

cd benjojo
cd dubstep-data
go env
go build

Once go has compiled the main file, you will need to edit the bash script 'prep-wav.sh'.

Change ./ASK-dubstep -input in.f64.data -data "$2" to ./dubstep-data -input in.f64.data -data "$2"

This will be fixed at a later date.

./prep-wav.sh "*.wav" "`date`"

If you encounter an error with Sox, saying that the "filter frequency must be less than sample-rate / 2", this might be an indication that the wav file is corrupt or too small.

The script file will complete, creating new files, most importantly the 'encoded-bassline.wav'.

Move to the decode folder

cd decode
go build
ffmpeg -i ../encoded-bassline.wav -f f64le -ar 44100 -ac 1 -y in.f64.data

To show steganograph:

mkfifo sound
ffplay -f f64le -ar 44100 -ac 1 -i sound & cat in.f64.data | tee sound | ./decode -input /dev/stdin

Otherwise run cat in.f64.data | tee sound | ./decode -input /dev/stdin

To view the decoded message: ./decode