Datavideo KMU-300, Инструкция по эксплуатации

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
Main

Baseline
Entropy
There are two coding options available for generating H.264 content:

CAVLC (Context-Adaptive Variable Length Coding)

CABAC (Context-based Adaptive Binary Arithmetic Coding)
CABAC encoding provides a 7-10% quality improvement over CAVLC but requires an extra
10-15% CPU. CABAC encoding is only available in H.264 Profiles Main & High. When
targeting at low-powered devices, such as older cell phones and tablets, we recommend the
Baseline Profile that uses CAVLC which requires less computing power.
GOP
GOP pattern with longer GOP length encodes video very efficiently. Shorter GOP lengths
usually work better with video that has quick movements, but they do not compress the
data rate as much. Depending on your applications, the NVS-31 MARK IV offers the user 16
GOP sizes ranging from 1 to 255.

255

240

200

120

100

60

50

30

25

20

15

10

5

3

2

1
Audio Bitrate (bps)
Audio Bitrate is the compression ratio for encoding the input audio source. The higher the
bit rate, the better the sound quality and file size. The NVS-31 MARK IV provides five audio
bitrate options for you to select, and the range is from 32Kbps to 384Kbps.

384K

256K