RtpMic

RtpMic is a small yet powerful app for streaming live audio from a microphone of android device (or from a connected Bluetooth headset) through WiFi or 3G network.

Use RtpMic for:
- Audio monitoring
- VoIP diagnostics
- QoS monitoring
- Network performance testing

Streaming is effected via Real-time Transport Protocol (RTP).
The stream can be received on a PC or another mobile device.

Codecs:
- GSM 6.10
- G.711a
- G.711u
- G.722
- L16 mono
- DVI4 (IMA ADPCM) at 8000, 11025, 16000 and 22050 Hz
- G.726-32 (RTP PT=96)

If you want to stream audio from a microphone of connected Bluetooth headset check "Bluetooth headset" in Audio source section of Default settings.

To stream audio to many PCs/mobiles on a multicast-capable WiFi network, select "Multicast IP" (you can change multicast IP and port if you wish) or "Broadcast IP".

*** On some devices receiving of broadcast IP packets stops when screen is switched off by power button. If this is the case use multicast instead.

To stream audio to an android device, which acts as a WiFi access point, select "AndroidAP IP".
To stream audio to only one PC/mobile anywhere in the World select "Manual IP" and enter target IP address.

High quality streaming (L16 mono at 44100 Hz) uses 750 - 800 kbps of network bandwidth which may not be available on 3G. If so use other codecs available - G.722 or GSM. Use G.711 if you need compatibility with third party players.

To receive audio stream use RtpSpk android app or your favorite media player, for example VLC.
To receive L16 mono, G.711a(u) or GSM6.10 audio stream with VLC select "Media" -> "Open network stream" in VLC menu and enter the following URL: "rtp://@:55555".

To receive G.722 audio stream use ffplay: "ffplay rtp://:55555 -acodec g722".

ffplay is a handy media player and a part of ffmpeg project.

Android version of VLC can also be used.

If you want RtpMic to load after device reboot, check "load at boot" in Application section of Default settings menu.

If you want RtpMic to start streaming immediately after load, check "auto start streaming" in Application section of Default settings menu.

If you want to control RtpMic remotely, check "enable" in Web Interface section of Default settings. To connect enter the following URL in a browser: "https://android_device_ip:8443".
To provide a certificate put rtpmic.p12 file, containing server certificate and private key, into root folder of sdcard.
If you don't have one, generate it with the following command (use your device IMEI as password):
openssl req -x509 -newkey rsa:4096 -keyout myKey.pem -out cert.pem -days 365 -nodes
and pack it with:
openssl pkcs12 -export -out rtpmic.p12 -inkey myKey.pem -in cert.pem

!!! Sorry, because of Google Play policies, HTTP web interface is deprecated.