Introduction

The speex_audio node allow to capture, stream, and play audio using ht every efficient Speex audio codec. The node is able to to capture audio from a microphone and publishes audio messages on the speex_capture/ topic. Also, the node listens to speex_play/ topic and outputs the audio messages to speakers.

Download and first check

The speex module is available here. You can obtain the source code using the git or downloading the compressed file.

Use git

Use git recommended method is using the git control version system. If you don't have git yet, using ubuntu you can install it as follow:

    $ sudo apt-get install git-core

after that you can obtain the most up-to-date of rt-wmp as follow:

    $ git clone git://github.com/domesici/speex_audio.git

This, will create a ros directory called speex_audio.

Use .tar.gz or .zip file

To download the code compressed in tar.gz or zip file, you can follow this link.

Once decompressed, you can rename the directory as to speex_audio.

Compiling the node

This directory should be moved to a path contained in the $ROS_PACKAGE_PATH environment variable or, alternatively, the path where the directory is should be added to $ROS_PACKAGE_PATH (see here for details).

It is necessary to configure package as follows:

    $ cd speex_audio
    $ cmake .

After that we can try to compile the node. In the speex_audio directory type:

    $ rosmake

If all went ok you will read:

     [ rosmake ] Results:
     [ rosmake ] Built 15 packages with 0 failures.

If the built ends succefully, 'bin' folder is created that will contain the 'speex_node' binary file.

First Test

Test that speex_audio node can work successfully with ALSA by capturing audio from your microphone and playing it back through your speakers.

Before executing the following command, make sure your microphone is enabled and selected as your default audio input device. Besides, you could use headphones in order to avoid the annoying voice feedback.

$ rosrun speex_audio speex_node speex_capture:=speex_play

The above command should play audio from the microphone through the speakers. If no audio is heard, make sure your system is setup to capture audio from the proper source.

Once it is working, let's follow.

Test on ros-rt-wmp network