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AXIS M3007–PV
Video
•
Double Panorama
•
Quad View
H.264
H.264, also known as MPEG-4 Part 10/AVC, is a video compression standard that provides high quality video streams at low bit rates.
An H.264 video stream consists of different types of frames such as I-frames and P-frames. An I-frame is a complete image whereas
P-frames only contain the differences from previous frames.
The
GOV length
is the number of frames between two consecutive I-frames. Increasing the GOV length may save considerably on
bandwidth requirements in some cases, but may also have an adverse affect on image quality.
The Axis product supports two
H.264 profiles
. The Main profile provides higher compression than the Baseline profile with the same
video quality, but requires more processing power to decode.
The bit rate can be set as
Variable Bit Rate
(VBR) or
Constant Bit Rate
(CBR). VBR adjusts the bit rate according to the image
complexity, using up more bandwidth for increased activity in the image, and less for lower image activity. CBR allows you to set a
fixed
Target bit rate
that consumes a predictable amount of bandwidth. As the bit rate would usually need to increase for increased
image activity, but in this case cannot, frame rate and image quality are affected negatively. To partly compensate for this, it is
possible to prioritize either frame rate or image quality. Not setting a priority means that frame rate and image quality are equally
affected. You must save your settings before they can take effect.
The current bit rate can be set to appear as text overlay. To do this, select the
Include text
check box option under
Overlay
Settings
and enter the modifier
#b
in the field.
MJPEG
Sometimes the image size is large due to low light or complex scenery. Adjusting the maximum frame size helps to control the
bandwidth and storage used by the Motion JPEG video stream in these situations. Setting the frame size to the
Default
setting
provides consistently good image quality at the expense of increased bandwidth and storage usage in low light. Limiting the frame
size optimizes bandwidth and storage usage, but may give poor image quality. To prevent increased bandwidth and storage usage,
the maximum frame size should be set to an optimal value.
Stream Profiles
A stream profile is a set of predefined stream settings including resolution, compression, frame rate and overlay settings. Stream
profiles can be used:
•
When setting up recording using action rules. See
Events, on page 31
.
•
When setting up continuous recording. See
Continuous Recording, on page 35
.
•
In the Live View page – select the stream profile from the
Stream profile
drop-down list.
For quick setup, use one of the predefined stream profiles. Each predefined profile has a descriptive name, indicating its purpose. If
required, the predefined stream profiles can be modified and new customized stream profiles can be created.
To create a new profile or modify an existing profile, go to
Setup > Video
>
Stream Profiles
.
To select a default stream profile for the Live View page, go to
Setup > Live View Config
.
Camera Settings
The
Video > Camera Settings
page provides access to advanced image settings for the Axis product.
Image Appearance
Increasing the
Color level
increases the color saturation. The value 100 gives maximum color saturation. The value 0 gives a
black and white image.
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