Kivy Tensorflow Hello World

This is a "Hello World" for running Tensorflow Lite on iOS, Android, MacOS, Windows and Linux using Python and Kivy.

Create a Tensorflow Lite model

You can use the Jupyter notebook in notebooks to create a Tensorflow Lite model file. A dummy example is provided for testing purposes.

Install buildozer

Install basic Python requirements (all platforms)

pip install buildozer cython

Follow the instructions for your platform here.

MacOS, Windows and Linux

pip install tensorflow numpy kivy
python3 main.py

Android

Currently you can only build for Android using buildozer on Linux.

Use the included buildozer.spec file or make the following changes to one created by buildozer init

source.include_exts = py,png,jpg,kv,atlas,tflite
requirements = python3,kivy,numpy
android.api = 30
android.minapi = 24
android.gradle_dependencies = org.tensorflow:tensorflow-lite:+,org.tensorflow:tensorflow-lite-support:+

Note that if your tflite model file is too big to be packaged with your APK, you will have to find some other way of getting it on to the device. If this is the case then change this line to ensure it is not included in the package.

source.include_exts = py,png,jpg,kv,atlas

Change the architecture you are building for to match that of your device or emulator

android.arch = x86

Build the APK

buildozer android debug

and install it with

adb install bin/myapp-0.1-x86-debug.apk

iOS

Remember that you will need an Apple developer account to be able to install your app on a real iPhone.

Install prerequisite system packages

brew install cocoapods pkg-config autoconf automake

Install additional Python requirements

pip install pbxproj cookiecutter

Build your app and install the Tensorflow Lite pod

buildozer ios debug
cd .buildozer/ios/platform/kivy-ios/myapp-ios/
cp YourApp/Podfile .
pod install
open -a Xcode myapp.xcworkspace

As indicated in the warning messages, you will need to make some changes to the project configuration. You can either do this by editing myapp-ios\myapp.xcodeproj or by editing the Build Settings for myapp in Xcode. Search for GCC_PREPROCESSOR_DEFINITIONS and add $(inherited) to the Debug target. Then repeat the process for HEADER_SEARCH_PATHS, OTHER_LDFLAGS and (possibly) EXCLUDED_ARCHS[sdk=iphonesimulator*] for all targets. Now you should be able to build and run your app. All being well you should see the following output (give or take rounding errors)

[[ 0.01647118,  1.0278152 , -0.7065112 , -1.0278157 ,  0.12216613, 0.37980393,  0.5839217 , -0.04283606, -0.04240461, -0.58534086 ]]

Every time you build you will need to run buildozer ios debug and then build and deploy from Xcode.