Datavideo NVS-34, Instruction Manual

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Level
ID Max. Video
Bitrate in
kbits/s Max Frame
Size in
macroblocks Max decoding
speed in
macroblocks
per second Resolution, Frame Rate
(Max Stored Frames)
3.1 14000 3600 108000 720×480@80.0 (13)
720×576@66.7 (11)
1,280×720@30.0 (5)
3.2
(HD) 20000 5120 216000 1,280×720@60.0 (5)
1,280×1,024@42.2 (4)
4.0 20000 8192 245760 1,280×720@68.3 (9)
1,920×1,080@30.1 (4)
2,048×1,024@30.0 (4)
4.1
(FHD) 50000 8192 245760 1,280×720@68.3 (9)
1,920×1,080@30.1 (4)
2,048×1,024@30.0 (4)
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, you can select 16
GOP sizes ranging from 1 to 255.

255

240

200

120

100

60

50