VK2-1080BXDNe manual V1.0
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4.3 Audio
This camera supports full duplex audio.
4.3.1 Audio - Basic
Use the Audio tab to manage and configure the basic audio settings for the camera.
Audio Setting:
Click the Enable audio checkbox to enable audio. This page describes how to
configure the basic audio settings for the camera.
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.
NOTES
- 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.