Mjpeg Settings - Axis 215 PTZ User Manual

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 Settings

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 bandwidth and storage usage during low light. Limiting the frame size will prevent
excessive bandwidth and storage usage, but image quality will suffer. To prevent increase in bandwidth and
storage usage, the maximum frame size should be set to an optimal amount. During ideal light conditions follow
these instructions to optimize frame size:
1. Click the View button and a pop-up window appears with Frame size and Compression in the text field.
2. Note the current frame size. To calculate a maximum frame size add 10 - 20% to the current frame size.
3. Enter the calculated frame size in the Limited to... field.
4. Verify the quality of the image in low light. Increase the maximum frame size if needed.
Note:
The maximum frame size allowed increases compression in order to maintain a low frame size starting at the compression value set
under Image Settings > Image Appearance > Compression. When compression is 100, the image cannot be made smaller. You may also
need to adjust the Resolution setting if a smaller frame size is needed.
For more information on these settings please refer to the online help
AXIS 215 PTZ/AXIS 215 PTZ-E - Setup
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