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Audio
Use the Audio tab to manage the basic audio settings for the camera.
Figure 15. Basic Configuration / Audio
Audio Setting:
Click the Enable audio checkbox to enable audio. This page describes how to
configure the basic audio settings for the camera. This camera supports the audio full duplex that
can be transmits and receives audio in both directions at a time.
Compression type:
G.711 is the international standard for encoding wired-telephone audio on
64kBit/s channel. It is a PCM (Pulse Code Modulation) scheme operating at 8 kHz sample rate. The
default setting is G.711 µ-law.
Sample rate:
Indicates the number of times per second the sound is sampled. The default
setting is 8 kHz.
NOTE
G.711, also known as Pulse Code Modulation (PCM), is a very commonly used waveform codec.
G.711 uses a sampling rate of 8,000 samples per second, with the tolerance on that rate 50 parts
per million (ppm). Non-uniform quantization (logarithmic) with 8 bits is used to represent each
sample, resulting in a 64 kbit/s bit rate. There are two slightly different versions; μ-law, which is
used primarily in North America, and A-law, which is in use in most other countries outside North
America. G.711 μ-law tends to give more resolution to higher range signals while G.711 A-law
provides more quantization levels at lower signal levels.