Mjpeg - Axis 214 PTZ User Manual

Video object type can be:
• Simple - This sets the video coding type to H.263, as used by e.g. QuickTime.
• Advanced Simple - Sets the video coding type to MPEG-4 part 2, as used by e.g. AMC (AXIS
Media Control). This is the recommended setting.
ISMA compliant - This option when enabled configures the generated stream to be ISMA compliant, which
includes limiting the bit rate to 1500 kbit/s.
GOV Settings
The GOV structure can be set to either I or IP, which describes the type of images included in the video
stream, as well as their internal order. The IP-structure generally sends the differences compared to the
previous image and far fewer complete images, so this method uses much less bandwidth than the
I-structure. The I-structure gives higher frame rates when using a high resolution, but requires more
bandwidth.
The GOV length determines the sum total of P-images and I-images in a GOV. Setting the GOV length to a
high value saves considerably on bandwidth. However there may be noticeable decay in the image at high
values.
Note:
GOV = Group of VOPs
VOP = Video Object Plane
Video Object Plane = image
Bit Rate Control
Limiting the maximum bit rate is a good way of controlling the bandwidth used by the MPEG-4 video
stream. Leaving the Maximum bit rate as Unlimited will provide consistently good image quality, but at the
expense of increased bandwith usage whenever there is more activity in the image. Limiting the bit rate to
a defined value will prevent excessive bandwidth usage, but images will be lost when the limit is exceeded.
Note that a maximum bit rate can be used for both variable and constant bit rates.
The bit rate type can be set as Variable Bit Rate (VBR) or Constant Bit Rate (CBR). VBR will adjust the bit
rate according to the images' complexity, thus using a lot of bandwidth for a lot of activity in the image
and less for lower activity in the monitored area.
Note:
Depending on the amount of motion, the required bandwidth may increase by 1-15% for each frame.
Video Stream
This parameter can be set to frame rate to increase the frame rate by 30% in 4CIF resolution. If the
resolution is set to a value lower than 4CIF, the parameter should be set to bandwidth.

MJPEG

In some situations the image size may get
quite large due to low light or complex
scenery. Adjusting the Maximum frame size
is a good way of controlling the bandwidth
and storage used by the MJPEG video stream
in these situations. Leaving the frame size as
Unlimited will provide consistently good
image quality at the expense of increased
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