Difference between revisions of "Video API Extensions legacy"

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Given realization of Video API has a number of opportunities which are absent in standard Axis Video API.
 
Given realization of Video API has a number of opportunities which are absent in standard Axis Video API.

Revision as of 13:53, 21 December 2005

Template:Ru=Video API Extensions.Ru

Given realization of Video API has a number of opportunities which are absent in standard Axis Video API.


Extensions enabling

By default the Video API extensions are blocked. For unblocking it is necessary to establish a corresponding variable:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ElphelExtensions.Enabled=yes


Obtaining of static and dynamic images

The standard interface for the static and dynamic images obtaining in JPEG and MJPEG formats is have a few additional parameters.

e_dcm_hor - horisontal decimation (resolution/image size reduction)
e_dcm_vert - vertical decimation (resolution/image size reduction)
e_bin_hor - horizontal binning (sensitivity for lower resolution)
e_bin_vert - vertical binning (sensitivity for lower resolution)
e_woi_width - sensor active window width (before decimation)
e_woi_height - sensor active window height (before decimation)
e_woi_left - sensor active window left margin (before decimation)
e_woi_top - sensor active window top margin (before decimation)
e_virt_width - virtual frame width
e_virt_height - virtual frame height
e_fliph - flip (mirror) image horizontally (uses in-sensor capabilities)
e_flipv - flip (mirror) image vertically (uses in-sensor capabilities)
e_color - consider sensor to be the color one, if not - skip Bayer color filters processing
e_quality - JPEG Quality (%)

Examples

Example of the static image obtaining with using the next parameters:

http://192.168.0.9/axis-cgi/jpg/image.cgi?e_dcm_hor=2&e_dcm_vert=2&e_woi_width=1000&e_woi_height=900&e_woi_left=600

Example of the dynamic image (MJPEG) obtaining with using the next parameters:

http://192.168.0.9/axis-cgi/mjpg/video.cgi?e_dcm_hor=2&e_dcm_vert=2&e_woi_width=1000&e_woi_height=900&e_woi_left=600

You can play this videostream, for example, by using the MPlayer (more detailed description see at Using Mplayer With Video API.Ru):

$mplayer -demuxer lavf "http://192.168.0.9/axis-cgi/mjpg/video.cgi?e_dcm_hor=2&e_dcm_vert=2&e_woi_width=1000&e_woi_height=900&e_woi_left=600&bogus.mjpg"

If any from parameters is not specified, the default values are used. You can find these values at the address:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=list&group=ImageSource.I0.Sensor

Note: All API extensions have the prefix "E_".

You can change the default value by standard way for Axis Video API. For example:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ImageSource.I0.Sensor.E_DcmHor=1

Obtaining the information about the system condition and default values

For obtaining the information about the system condition variable you must use the next path:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=list&group=ImageSource.I0.E_CurrentState

In an addition to the obtaining of the standard "rfc" format there is the obtaining in XML format also. You must use the responseformat parameter for it. For example:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=list&group=ImageSource.I0.E_CurrentState&responseformat=xml

Note. If the responseformat not specified or specified incorrect, will be used the default value of "rfc".


Video streaming RTP/MJPG and RTP/Theora

The Elphel cameras can transfer the video stream by RTP protocol.

RTP/MJPG

RTP/Theora

Exposure control

The Elphel cameras support the standard and advanced exposure control interface. About the standard settings see First_Acquaintance_With_Video_API.Ru

For autoexposure enabling is necessary to use the following command:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ImageSource.I0.Sensor.Exposure=auto

Enabling the manual control of exposure:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ImageSource.I0.Sensor.Exposure=manual

Obtaining the exposure state:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=list&group=ImageSource.I0.E_CurrentState.E_Exposure

Window settings:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ImageSource.I0.Sensor.E_Exposure.E_WinWidth=30&ImageSource.I0.Sensor.E_Exposure.E_WinHeight=45&ImageSource.I0.Sensor.E_Exposure.E_WinLeft=10&ImageSource.I0.Sensor.E_Exposure.E_WinTop=20

Exposure max.values:

http://192.168.0.9/axis-cgi/admin/param.cgi?action=update&ImageSource.I0.Sensor.E_Exposure.E_Max=3000&ImageSource.I0.Sensor.E_Exposure.E_OverMax=30