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Interact with C++ program from android using parcelable class

Basically, I have a C++ program that finds the sum of two numbers given. I need to provide the two numbers to the C++ program as input using my android app and then display the result in my android app. I guess I need to use parcelable class. Can someone please tell me the steps to be followed?
Edit: I forgot to mention that the C++ program that I intend to communicate with is an executable program (sum.exe)

To run a C++ executable on Android, you can use something like Runtime.exec("sum 1 2"). There are a lot of tutorials, e.g. https://www.mkyong.com/java/how-to-execute-shell-command-from-java/. The output (stdout and stderr) can be parsed, too. A more sophisticated way is to use ProcessBuilder, but the idea is the same.
If you want your executable to keep running in background, and send the numbers to crunch once in a while, you can either use input pipe, or some IPC protocol. Shared memory works well, see e.g. How to use Shared Memory (IPC) in Android.

You can use JNI code, take a look here:
https://github.com/mkowsiak/jnicookbook/tree/master/recipes/recipeNo025
where you can find super simple code with C++ being called via JNI wrapper from Java.

Matlab audioread/audioplay into C/C++ through Coder

I am working on a matlab project where I add effects to audio files (mp3, wav). Therefore, I load the files into arrays using the matlab function audioread(..).
Now, I want to export this to Android. I read that the best way is to use the Matlab Coder to export the matlab code to C/C++ (or Java) and then export it into android (more or less).
However, the function call audioplayer (and play) are Unsupported (that's what the code generation readiness issues says).
What can I do ? One idea was to play the sounds directly using c++ code (so after the code generation). But how to play sounds from arrays using c++ ?
Or if you guys have others ideas without touching c++ codes (so fixing the problem directly in matlab), I would be glad to hear it !
Thanks and have a good day !

Typically what I recommend in cases like this is to factor your code in two pieces:
The part that does the audio file I/O and audio playing (namely the OS-specific part)
The computational kernel for which you will generate code using MATLAB Coder. This piece usually takes numeric arrays representing the image or audio data as arguments.
I've used this approach to leverage MATLAB Coder generated code to do image filtering on Android.
To do part (1), as Navan says, you'll need to use Android APIs to read in audio files, write data back to files, and to play them as desired. Note, I haven't done extensive Android development, so doing these tasks may take some research or be difficult.
Once you have the data in a format suitable for the function(s) in (2), likely a numeric array, then you can call your generated code using JNI to add the desired effects. The generated code would return the data back to the Java code and you can then encode it, play it, or do as you please with it using the Android APIs.

Playing audio normally uses platform dependent libraries. In DSP System toolbox, there is an audio player object called dsp.AudioPlayer which supports C code generation. But I believe this uses platform dependent libraries in the generated code and it will not be straight forward to make it work in Android. You will be better off finding an audio player library for Android and hooking that in manually after generating code.

Can we implement MATLAB code on Android? [duplicate]

This question already has answers here:
How to integrate Matlab code library with Android?
(6 answers)
Closed 8 years ago.
I basically am using MATLAB for image processing. I want to develop an Android app which can support the processing provided by MATLAB. I searched for results about it but failed to get clarity out of it.

If you have an additional product, MATLAB Builder JA for Java, you can produce a .jar file from your MATLAB code.
However, the .jar file requires the MATLAB Compiler Runtime (a freely
redistributable component that you get with MATLAB Compiler and MATLAB
Builder products) to be present. The MCR has a much larger footprint
than is suitable for the typical Android device (it's like a copy of
MATLAB itself, without the user interface).
You could think about either
Running your MATLAB .jar file remotely on a server, and having your Android application connect to it, or
Instead of using MATLAB Compiler and Builder products, use MATLAB
Coder, which will convert a subset of the MATLAB language directly
into C code. This C code doesn't require the MCR, and could be
compiled to run directly on Android. Make sure your MATLAB algorithm
falls within, or can be expressed in, the appropriate subset of the
MATLAB language.
More infos can be found here from Sam Roberts post

How to integrate Matlab code library with Android?

I have an algorithm and some other code which is in MATLAB and I want to use it in my Android application.
How can I do this?
Can I make a jar file from MATLAB for use with Android?
I have to do something else?

If you have an additional product, MATLAB Builder JA for Java, you can produce a .jar file from your MATLAB code.
However, the .jar file requires the MATLAB Compiler Runtime (a freely redistributable component that you get with MATLAB Compiler and MATLAB Builder products) to be present. The MCR has a much larger footprint than is suitable for the typical Android device (it's like a copy of MATLAB itself, without the user interface).
You could think about either
Running your MATLAB .jar file remotely on a server, and having your Android application connect to it, or
Instead of using MATLAB Compiler and Builder products, use MATLAB Coder, which will convert a subset of the MATLAB language directly into C code. This C code doesn't require the MCR, and could be compiled to run directly on Android. Make sure your MATLAB algorithm falls within, or can be expressed in, the appropriate subset of the MATLAB language.
Edit: As of R2015a, functionality from MATLAB Builder JA for Java has been replaced by a new product, MATLAB Compiler SDK.

I am the developer of Addi. http://addi.googlecode.com Addi is quickly becoming a full port of Octave (which is an open source tool that uses Matlab syntax). Addi is going to have intents for other applications to use it as their math engines or plotting engines. So, if you can run your code on Octave, then very soon you will be able to run it on Android.

Our only option is to get C++ code from M code using MATLAB Coder toolbox, that generates standalone C and C++ code from MATLAB® code. It supports only some subset of all Matlab functions, therefore might be not suitable for your needs.
Having C code you can compile it using NDK. MATLAB Compiler is not an option here.

A new feature in Matlab 2014a:
http://www.mathworks.com/help/simulink/samsung-galaxy-android-devices.html
You can now directly install (limited set of) models to Samsung Android devices, and this should work actually on any Android device.

You can convert matlab code into python and then use the python code in the android .There are many tools to do this conversion. Python goes well with android than matlab.

You have 2 options,
Create a JAR and include in your Java Application and start using it. (I have not tested this by creating a JAR outside Eclipse)
You can code the same thing in C and use Android NDK to process it. (This will be faster and safer way)

Replace string in a function at runtime Android NDK

I have an external compiled static C++ library that I'm using in my android application. This library is reading a file. I want to know if there is a way I can "redirect" the function that's reading the file so that it reads another file.
So if it does:
fopen("myfile.txt", "rb");
I want to intercept it and to do this instead:
fopen("myotherfile.txt", "rb");
In Objective-C I use MethodSwizzling. Is there something similar I can do in C++ or the android NDK?

Short of editing the binary (with uncertain results), your best option is to use a symlink... if you're just doing it for development purposes, you could use adb shell into your test device to create the symlink.
http://developer.android.com/guide/developing/tools/adb.html#issuingcommands

How about contact the author of the library and ask them to introduce a parameter? Having hard-coded file paths is a lousy design anyway, the library will be better off.