User`s manual

AXIS 223M - Audio
17
Audio
The AXIS 223M can transmit audio to other clients using a connected external microphone and can play audio
received from other clients via connected speakers. This section describes how to configure the basic audio
settings for the AXIS 223M, e.g. set the communication mode and adjust the sound levels in the microphone and
speakers connected to the camera.
Note: The speakers connected to the audio output must have a built-in amplifier, e.g.
PC speakers.
Audio Settings - Enable Audio
Check this box to enable audio in the AXIS 223M.
Audio Channels - Audio mode
Half-duplex mode transmits and receives audio in both directions,
but only in one direction at a time. This means that you must select
when to receive or transmit audio with the push-to-talk button. To
speak, press and hold the button (check that the microphone is not
muted). When finished speaking, release the button and you will
receive audio from the other end of the connection.
Note that the push-to-talk button is configured from AMC. It is also possible to configure the push-to-talk
button so that it toggles between speaking and listening modes.
When selecting Simplex - Network Camera speaker only mode, the speaker connected to the camera will play
audio, but no audio will be transmitted from the camera to other web clients. This could be used to e.g. provide
spoken instructions to a person seen in the camera. This mode requires you to use the push-to-talk button.
Simplex - Network Camera microphone only mode transmits audio only from the AXIS 223M to web clients. It
will not receive audio from any other web clients. This can be used in remote monitoring, web attractions etc.,
to provide live audio, as well as video, of a monitored situation.
When using half-duplex, the Send the sound from the active client to all other clients option transmits the
audio signal from the client that is talking to all the other clients.
Audio Input
Audio from a connected microphone or a line source can be connected to the Audio in connector of the AXIS
223M. The audio source must be set to Microphone or Line depending on the connected device.
The Enable microphone power option provides DC power for an external microphone. If using a small electret
condenser microphone such as a clip-on mic or a PC microphone, this option needs to be enabled.
Note: To use a high impedance dynamic microphone, DC power should not be enabled. DC power will not harm the microphone, but if you are
uncertain, try switching it off and on. The default value is DC power enabled. To use a professional microphone requiring 48V phantom
power, you need an external power supply and must use a balanced-unbalanced converter (audio transformer) in between.
If there are problems with the sound input being too low or high, adjust the input gain for the microphone
connected to the AXIS 223M.
Select the desired audio Encoding format, AAC, G711, G726.
Select the desired Sample rate (the number of samples of a sound that are taken per second). The settings
depend on the available bandwidth and the required audio quality, i.e. 16kHz produces better sound but requires
more bandwidth.
Depending on the selected encoding, set the desired Bit rate (audio quality). The settings depend on the
available bandwidth and the required audio quality, i.e. a high bit rate setting requires more bandwidth.
Client PC
TCP/IP Network
Example of a network
using AXIS 223M cameras to transmit
audio and video across the network.