Huffman encoder-decoder

This is a experiment using Huffman trees to create an "encryption" android app for passing around secret messages to your friends.

Do NOT consider this a serious data protection tool. It is merely part of a fun project that I created to play around with Huffman coding.

Deploying

Source: https://www.youtube.com/watch?v=pzsvN3fuBA0

Install buildozer

Note: clone the buildozer repo on your repos folder

git clone https://github.com/kivy/buildozer.git

cd buildozer

sudo python3 setup.py install

Install dependencies

sudo apt-get update
# sudo apt-get install openjdk-8-jdk # might not be necessary
sudo apt install python3.9-distutils
# sudo apt install cython # Commented out because doesn't work and doesn't seem to be needed
# sudo apt install build-essential libltdl-dev libffi-dev libssl-dev python-dev-is-python3
pip3 install --user --upgrade Cython==0.29.33
sudo apt-get install zip
sudo apt install zip unzip openjdk-17-jdk python3-pip autoconf libtool pkg-config zlib1g-dev libncurses5-dev ipython3

Build and deploy the APK

buildozer android debug

If you want to delete an existing build first, add the clean argument

If you want to deploy onto an already connected phone, add the deploy argument. You can also make it run right away with run. Add logcat to get logging.

Phone config

• Enable developer options: Settings > About > look for build number and tap 7 times
• Go to Dev Options and enable:
  • Stay awake
  • Enable USB debugging (accept the prompts on the phone)

Connect to phone with adb

adb tcpip 5555

Click allow again on the phone

Look for your phone's local ip address (About phone > Status)

adb connect [IP]:5555

Deploy APK

adb devices

adb -s [DEVICEID] install [NAME_OF_APK_FILE]

If installation fails due to NO_MATCHING_ABIS, you might need to check which architecture the phone uses and change buildozer.spec accordingly. After any changes to the spec, you need to run buildozer appclean and rebuild.

The line below in the spec can build multiple architectures and then you can choose:

android.archs = arm64-v8a, armeabi-v7a

Debugging

adb -s DEVICE_ID logcat *:S python:D