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.

Extensions enabling

By default the Video API extensions are blocked. For unblocking it is necessary to set 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 MJPG 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 (MPJPG) 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.

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