Solving issues on 2 Applications - PC (Mjsip) and Android (Sipdroid) for sending-receiving Voip.


I'm developping a software that needs, among various other functionalities, to perform Voip communications. I have one applications on PC side and another on Android side.

I'm using as Voip library: on Android clients the libraries "Sipdroid"; on Pc clients the library "Mjsip". I have some issues to be solved.

I'll provide to the Freelancer 2 simple apps (the source code), one for PC (in Java, developped on Netbeans) and one for Android (on Android Studio).

Each app simply send and receive voip packets: the 2 applications perform only the pure Voip job: no GUI is required; no signalling is needed for call setup, it is already done by my main application.

The voip comunication is pure peer-to-peer, so it works without any server.

Being the 2 applications already done, the developper doesn't have to write those, it has only to solve some issues.


- To get perfectly working the 2 applications, in order to have voip calls between:

a) 1 android and 1 PC (that is for me the most important case)

b) 2 androids

c) 2 PCs

- The job is done and specs are 100% satisfied when the 2 applications allow to have a voip call with very good quality, without any speech lost or delay, in the mentioned cases a), b) and c).

- The codecs to be used/implemented must be at least: OPUS, GSM, PCMA, PCMU. It means that the 2 appplication must be able to work at least with all the 4 codecs. Inside the code here provided, the selection is done by setting a parameter.

- The application for PC must work with whatever PC, Windows or Linux, so not depending from audio board for example.

- The application for Android must work with whatever Android device, with Android 4.0 version or later.

- On transmitting, the voice trasmission (then the Voip packet sending) must start immediately after the method is invoked, without any delay.

- On receiving, the voice playing on speaker must start immediately after the method is invoked and packet are received, without any delay.

- The developper will have to get available some static methods (to be invoked from classes of my main application) to activate/disactivate:

- SpeakerPhone (only on Android side); already developped

- Bluetooth (only on Android side) ; already developped

- Mute of microphone (both PC and Android side)


- On PC side, it works with only some PC, depending from audio board; the freelancer will have to sove this problem so to work properly indipendently from PC used.

- On PC side, GSM codec doesn't work properly.

- On both PC and Android side, Opus codec is missing, so the freelance has to provide (it is available on the web) and get it working.

- On Android side I have different behaviours depending from Android device; for example with some devices I loose the first 2-3 seconds of speech.

- Other issues can be present, but not discovered by me.


- The source code must be delivered to the buyer.

- The developper will have to support me (replying to my questions for clarification), when I'll have to integrate his job inside my main application.

- The developper will have to support me (replying to my questions for clarification), about parameters to be used for optimization of voip.

- The application for PC must be opened in Netbeans IDE, without any adaptation.

- The application for Android must be opened in Android Studio IDE (ver 1.3.2), without any adaptation.


Due to one freelancer that tryied to do a fraud, and also according to Freelancer site best practize, I'll NOT pay any milestone in advance. Any milestone will be realised when I'll get the source code with some targets reached.

The developper will have to get available:
- option to save voip streaming in audio file (in standard format: .amr, .wav, .mp3); the pathname of the file will have to be a parameter setted by my main app. Therefore if this option is activated the voip streaming will be saved in a local file. The choosing of file audio format will be discussed with me.
- option to run encrypted Voip; the encryption key will have to be a parameter setted by my main app.Therefore if this option is activated the voip packets will be encrypted according to setted key.

Habilidades: Android, Java, Mobile App Development, VoIP

Veja mais: write on communications, write my speech for me, write code freelance, write application for job, works for freelance, work freelance with this app, work freelance windows server, work apps freelance, windows server job for freelance, windows server freelance, windows on android, windows freelance software, windows app freelancer, web work java freelance, web support freelance, web software developper, web java freelance, web ide java, web developper freelance job, web developper freelance, web application freelance, web app freelance, voip application mobile freelance, the best job in the freelance, the best freelance site

Acerca do Empregador:
( 7 comentários ) Roma, Italy

ID do Projeto: #10496420

5 freelancers estão ofertando em média €792 para esse trabalho


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