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6.2.1.
Serverpush modifiers
The following table explains serverpush modifiers.
Modifier
X value
Effect
snap=X
Spush
Uses server push connection
Spushn
Uses server push, but updates it at most every n seconds (n can be a floating
point) Spush with a value of 0 will send images as fast as the camera can acquire
them. Spush with a value of 0.2 will send five images per second.
For example, to request a serverpush stream downsampled by four at a frame rate of 4 frames per second use
the following URL:
http://<camera_ip>/now.jpg?snap=spush0.25?ds=4
6.2.2.
Image control modifiers
Image control.
Modifier
X value
Effect
ds=n
Downsamples image by the value of n (1, 2, 4, 8)
6.2.3.
Source/Destination resolution
Some cameras support the ability to request a “destination resolution” rather than just an integer downsample
value. The camera will format the source video to fit into the desired destination resolution. This insulates
the video recording system from having to know the specific resolution of the camera and just request the
desired resolution. This could be quite useful for things like multi-view displays.
Modifier
Effect
wl=n
window absolute left (lowercase
“
L
”
not the number
“
1
”
)
wt=n
window absolute top
wrw=n
window absolute raw width
wrh=n
window absolute raw height
wdw=n
window destination width
wdh=n
Windows destination height. If only one of the
“
wdw
”
or
“
wdh
”
parameters is specified a 1:1
aspect ratio will be assumed.
Note:
Absolute coordinates have (0,0) at the top left corner of the image.
For an example, to ask for a stream of 320 by 240 pixels, 10 pixels to the right and 20 pixels down from the
upper left corner of the full image, use the URL:
http://<camera_ip>/now.jpg?snap=spush&wl=10&wt=20&wrw=320&wrh=240
This request will deliver the 320x240 image as a separate serverpush stream, completely independent of any
other streams of data on the camera.
