AXIS Q7404 Video Encoder
Video and Audio
Audio Input
An external microphone or a line source can be connected to the Audio-in connector. Configure the audio input settings under
Video
& Audio
>
Audio Settings
.
Select
Microphone
to use an external microphone or
Line
to use a Line in device, e.g. an audio mixer for multiple microphones
or a microphone with a built-in amplifier, as audio source.
Select the microphone sensitivity level (
High/Low
) depending on the sound level in the monitored area. For example, if the Axis
product is installed in a noisy environment, try setting the input sensitivity to
Low
.
The
Microphone power
option provides DC power for an external microphone. Microphone power should only be used with
microphones that have no battery. This setting should not be enabled when using a dynamic or battery powered microphone.
Microphone power will not harm the microphone; if you are uncertain, try switching it off and on. To use a professional microphone
requiring 48 V phantom power, you need an external power supply and a balanced-unbalanced converter (audio transformer) in
between.
Use the
Input gain
to control the volume (dB Full Scale) of the audio input. If the sound is too low, choose a higher dB, to amplify
the sound. If the sound is too high, choose a lower dB. The
Level
bar gives a visual representation of the audio signal level in dB
relative to the full-scale input level.
•
Green — the signal is at a good level.
•
Yellow — the signal is becoming distorted.
•
Red — the signal is distorted.
Use the
Encoding
option to select digital audio encoding format.
•
AAC
requires a license for both encoding and decoding. AAC is the least complicated and most widely used codec. If
achieving the best possible audio quality is a priority, AAC is the recommended codec to use. An AAC license is included
in the Axis product.
•
G711
is an unlicensed standard codec that is useful when integrating audio into a VoIP system
•
G726
is an unlicensed speech codec that is most commonly used within the security industry.
The
Sample rate
defines the number of times per second the sound is sampled. A higher sample rate will provide better audio
quality, but also requires a greater bandwidth.
Set the required
Bit rate
depending on the selected encoding. A higher bit rate will give better audio quality. A lower bit rate
may have latency or delay, but will require less bandwidth.
For more information about these settings, please see the online help
.
Audio Output
An external speaker can be connected to the Audio-out connector (a built-in amplifier is required for this). The output can be
connected to another amplifier with speakers. A stereo connector must be used for the audio out.
Configure the audio output settings under
Video & Audio
>
Audio Settings
.
Output gain -
Control the volume (dB Full Scale) of the line audio output. If the sound is too low, choose a higher dB. If the
sound is too high, choose a lower dB.
Audio Clips
An audio clip is a sound file that can be played when events occur or directly from the
Live View
page. The audio clip must first be
uploaded to the Axis product or recorded by a microphone connected to the product.
To add, download, modify or remove audio clips, go to
Video & Audio > Audio Clips
. For more information see the online help
.
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