Difference between revisions of "External Live Stream"

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==Tips==
==Tips==
===A warning about scale===
Scale is used in the above to 'downscale' or downsample the video feed. ergo, if you run scale=50, the video feed will be at 50% resolution. The width and height will remain identical (in my example, where I set the width and height above). Why is this important? Because the higher resolution you use, the more CPU you will use. This comes into play with older 1 or 2 core machines / ARM based SBCs. For those machines, you generally want to set scale to be lower than 100. Failure to do this, will eventually lead to CPU / Memory errors which show up in the form of video feeds on the client dropping in and out, in a strange sort of artistic fashion.
===Quickly Change pixel settings for page===
===Quickly Change pixel settings for page===
It should be possible to use CSS and have the videos fill the page appropriately (I haven't gotten around to it. Contributions welcome.) but it's also possible to use sed here to adjust the pixels as needed:
It should be possible to use CSS and have the videos fill the page appropriately (I haven't gotten around to it. Contributions welcome.) but it's also possible to use sed here to adjust the pixels as needed:

Revision as of 18:01, 21 June 2021

Here is an html file you might use in a ZM client Desktop SBC Camera Monitor to view the streams from the ZM Server. You will need to adjust the resolution, number of cameras, and monitor id of the URL to your setup.

In my experience, Clients viewing the Streams (up to 3 clients, with 20+ cameras) do not slow down the ZM Server.

For more details, see Dummies_Guide#Watching_the_Cameras

<html><body bgcolor="black">
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=1&scale=100"&user="watchinguser"&pass="somepassword" >
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=2&scale=100"&user="watchinguser"&pass="somepassword" >
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=3&scale=100"&user="watchinguser"&pass="somepassword" >
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=4&scale=100"&user="watchinguser"&pass="somepassword" >
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=5&scale=100"&user="watchinguser"&pass="somepassword" >
<img width="412px" height="268px" src="http://IPOFZMSERVER/zm/cgi-bin/nph-zms?mode=jpeg&monitor=6&scale=100"&user="watchinguser"&pass="somepassword" >
</body>
</html>

Setup

In 1.32 and 1.34, you may have to adjust the following setting for auth_relay if authentication is used. Note that this conflicts with ZMNinja, which requires auth_relay to be set to hashed, I believe.

Post by rockedge» Fri Jun 30, 2017 8:09 pm
in a WordPress page or post I use something like this: Remember that 
with certain authorizations set, the URL would be slightly different.
this URL works when :
Options->System->OPT_USE_AUTH = ON
Options->System->AUTH_TYPE = Builtin
Options->System->AUTH_RELAY = NONE

Code: Select all

<h2><img class="aligncenter" 
src="http://your_zm_server/cgi-bin/nph-zms?mode=jpeg&scale=100&maxfps=5&buffer=1000&monitor=1&user=admin" alt="stream down" width="420" height="340" /></h2>

ref:https://forums.zoneminder.com/viewtopic.php?f=36&t=26292

Note that this URL omits password. But it is given in the preface example.

Tips

A warning about scale

Scale is used in the above to 'downscale' or downsample the video feed. ergo, if you run scale=50, the video feed will be at 50% resolution. The width and height will remain identical (in my example, where I set the width and height above). Why is this important? Because the higher resolution you use, the more CPU you will use. This comes into play with older 1 or 2 core machines / ARM based SBCs. For those machines, you generally want to set scale to be lower than 100. Failure to do this, will eventually lead to CPU / Memory errors which show up in the form of video feeds on the client dropping in and out, in a strange sort of artistic fashion.

Quickly Change pixel settings for page

It should be possible to use CSS and have the videos fill the page appropriately (I haven't gotten around to it. Contributions welcome.) but it's also possible to use sed here to adjust the pixels as needed:

sed -e 's/oldpx/newpx/g' -i cameras.html

Refresh Page Periodically

Refreshing the page is a good idea, so that any streams don't drop out for any reason. You can do this with xdotool (see Dedicated_SBC_Camera_Monitor#Refresh_Screen_Periodically )or possibly with html:[1]

<meta http-equiv="refresh" content="300">

Scale may be required for large numbers of cameras or SBCs

See that scale=100 option in the URL? That is used to (obviously) downscale the video stream. If you have a 2K stream, but you are viewing it at 640x480, you don't need 100% scaling. Lower the number to keep the bandwidth down.

Where this is required, is when you have a lot of monitors, say 20+ cameras. Or you have an SBC that can't handle full res streams. In these scenarios, if you don't scale, you will either see the CPU max out on the watching computer, or you will see video feeds drop in and out periodically. For more details, see how ZM handles the URL for montage.

Single Snapshot URL

The URL for a single snapshot is:

http://serverip/zm/cgi-bin/nph-zms?mode=single&monitor=2&scale=100&maxfps=5&buffer=1000&user=somename&pass=somepass

Adjust Monitor # as needed.

Alternative Single Snapshop JPG via ZMU

zmu is a binary, along with zma, and zmc that can do various functions. One of them is creating a jpeg.

/usr/bin# zmu -h
zmu <-d device_path> [-v] [function] [-U<username> -P<password>]
zmu <-m monitor_id> [-v] [function] [-U<username> -P<password>]
General options:
  -h, --help           : This screen
  -v, --verbose          : Produce more verbose output
 ...
  -i, --image [image_index]    : Write captured image to disk as <monitor_name>.jpg, last image captured
                   or specified ring buffer index if given.

ffplay

It is possible to use ffplay to directly stream a single camera feed (bypassing ZM) to the desktop. Although refreshing may be more involved.

ffplay -i rtsp://user:Password@ipaddress:554/video

See Also