Dedicated Camera Monitor
From:     https://wiki.zoneminder.com/Dedicated_SBC_Camera_Monitor


Intro Contents Desktop SBC Cam Mon RPI Mon 



Dedicated SBC Camera Monitor
A guide to setup an SBC (Beaglebone black) or Desktop that will monitor a
video feed from ZM. Simply add power, and the video feed will appear on boot.
OS will be Devuan Jessie, WM will be dwm, terminal st, and browser will be surf.
It will be a minimal installation. Leaner than LXDE, the default DE for beaglebone.
I'll include optional steps to setup Device Trees and the I2C peripheral
(Beaglebone specific) and read a sensor. Combine with ZMTrigger.
This is noticeably more difficult than connecting a coaxial cable to a CRT
such that an analog, older setup would have. But is more flexible. A desktop
is generally recommended here, but SBC's can be used as well.
After you setup this OS once, it's advisable to copy to an img and then
deploy on as many machines as necessary. A good size for the single OS root
partition might be 4GB.
Tested in 03/2017 on a Desktop and Beaglebone with Devuan Jessie

Note that in the end, due to faulty video display, I ended up using an old
laptop instead. A BBB is able to handle one stream, but seemed to have a bug
in the final deployment.

Update: 08/2018 Tested with Rpi3 and Debian Stretch migrated to Devuan Ascii
here Dedicated_RPI_Camera_Monitor

Another companion to this guide is the Desktop_SBC_Camera_Monitor

11/2018: See also Zoneminder Blogspot - ODroid XU4 Zoneminder Client guide.



Contents






Setup




Installation
Requirements

Install Beaglebone Black Debian Jessie using elinux.com's BeagleBoardDebian
page.

Use the direct image (under Demo, below NetInstall). Not the netinstall,
which is slower, unless you know what you are doing.

After booting from the SD card, make sure the network interface is set to load in:
	nano /etc/network/interfaces

Next, migrate to Devuan using Dev1fanboy Upgrade-Install-Devuan wiki guide.
Skip most of the part about the display environment. Reboot after apt-get
dist-upgrade. Try the purge of libsystemd0 in DE section, if you like. May
not work. RCN repo seems to want it.

Complete the following commands
	su root

Remove non-free from /etc/apt/sources
	nano /etc/apt/sources.list

	apt-get install xorg libx11-dev libxft-dev libxinerama-dev gcc make htopsudo tcpdump git

For Surf
	apt-get install libwebkitgtk-dev libgtk2.0-dev linux-headers-$(uname -r)

Download simple programs
	git clone http://git.suckless.org/dwm && git clone 
git://git.suckless.org/st && git clone git://git.suckless.org/surf

Edit the config for dwm
	nano dwm/config.def.h


	cd dwm
make
make install
cd ../st
nano config.def.h

	make
make install




Cleanup
	apt-get remove nfs-common rpcbind wpasupplicant avahi-daemon ofono apache2

Leave wpasupplicant if you use wifi. Net installer may want to install
acpid. Beware of removing cron. Just disable the service. Remove Exim4 if
you want.

At this point maybe 40MB RAM, and <5% CPU. Compare to LXDE.




Clock
Only needed if you are keeping time.
	# apt-get install openntpd

You can run ntpdate for manual updates but an ntpd daemon seems to run
better (albeit, it opens ports and uses more resources).




Auto Start
Edit .xinitrc, /etc/rc.local, /etc/inittab, and .bash_profile to auto startx
without requiring a login, load surf with the path of the zm server monitor
feed, and disable the screensaver.

Added to /etc/inittab (comment out existing, and add this below. Replace
username with your new user):

	1:2345:respawn:/bin/login -f USERNAME tty1 </dev/tty1 >dev/tty1 2>&1

Copy /etc/profile to user that will be auto logging in:
	cp /etc/profile /home/USERNAME/.bash_profile

Appended to /home/USERNAME/.bash_profile :
	exec startx

When startx loads, it will pull settings from ~/.xinitrc for USERNAME so
edit that (note that .xinitrc requires & after all commands that are not the
final wm).

	#!/bin/bash
/usr/local/bin/surf "localhost/zm/cgi-bin/nph-zms??mode=jpeg
&monitor=1&scale=100&maxfps=5&buffer=1000&user=user&pass=pass" &
exec dwm

Add an additional user beside the one used for the auto login, otherwise ssh
will fail. ssh will try to startx when it loads, and it won't be able to.
Add USERNAME2 permissions to sudoers.
	# adduser USERNAME2
nano /etc/sudoers

Disable screensaver for the first USERNAME per Arch Wiki: Display Power
Management SIgnaling
	nano /home/USERNAME/.xinitrc

export DISPLAY=:0 &
xset s off &
xset -dpms &

These go before the other commands in .xinitrc, as they have the & symbol.
The total .xinitrc will be something like:
	#!/bin/bash
export DISPLAY=:0 &
xset s off &
xset -dpms &
/usr/local/bin/surf "localhost/zm/cgi-bin/nph-zms??mode=jpeg
&monitor=1&scale=100&maxfps=5&buffer=1000&user=user&pass=pass" &
exec dwm

Note: When troubleshooting xset. You must be the same user that is running X
(ssh in as different user, then su to user). And, you must export DISPLAY to
:0 or similar. Finally xset q should query the current settings.




Fine Tuning
At this point, you should be able to boot the SBC or desktop and receive a
video feed without user interaction. However there are two problems
(Beagle). One, it is not full screen. Two, video may be flickering.




Flickering Video
This is a known issue with Beaglebone. The simple solution is: install
devmem2 or some other memory editing program, change an address. For details
of why this is occuring see: [1] and [2] or search online.

Steps:
	git clone https://github.com/VCTLabs/devmem2
cd devmem2
make
make install

Append the memory adjustment to rc.local
	nano /etc/rc.local
devmem2 0x4c000054 w 0x00FFFFF10

Watch syslog and FIFO errors should immediately stop upon entering write
command on memory.

Install steps source: Scivision: Devmem2 on the beaglebone black The author
of devmem2 (Jan-Derk Bakker, website and code found at lartmaker.nl), his
website is down at the moment. You can view the root domain at internet
archive, but the page for devmem2 is not available. Others like VCTLabs
above have copied his code to various spots. See also the Notes section
below.




Full Screen Video Feed
Two options come to mind:


First Is easiest. Make an html file. Be sure to include http prefix.
<html>
<img width="###px" height=###px" 
src="http://serverip/zm/cgi-bin/nph-zms?mode=jpeg&monitor=####&scale=100&maxfps=5&user=username&pass=password"/>
</html>

Call it on .xinitrc before dwm
	surf file:///home/username/file.html &

Customize the width and height of the img tag to fit your monitor. In my
case I put st in the .xinitrc of my beagle instead of surf, restarted, and
from the terminal ran xrandr to see what display it was using. I had
1440x900 but the width and height I could get out of surf without borders
causing trouble was 1415 and 875. Multiple img tags can be embedded into an
html file however you like. See also Example Camera View HTML




Refresh Screen Periodically
You will want to have the web browser refresh every few minutes. Otherwise,
if the feed drops out, it will not return unless you reboot. The way I
accomplished this was:

Install xdotool
	# apt-get install xdotool

Edit surf config.h and add the following to the keybindings section, then
make and make install.
	{ 0, GDK_F5,  reload, { .b = FALSE } },

Add to /etc/crontab
	DISPLAY=:0
*/5 * * * * username /usr/bin/xdotool key F5

To make sure this works, with the browser watching a camera stream, restart
apache2 on the ZM server, and the browser feed will freeze. A successful F5
from xdotool will refresh the screen, as long as surf has a keybinding for it.




Accessing headless X via VNC
In the case that you have a headless device (no monitor attached) yet X is
running, here's some tips for accessing the desktop via VNC.
	sudo apt-get install xserver-xorg-legacy
add:
allowed-users:anybody 
in /etc/X11/Xwrapper.config
apt-get install x11vnc

Final command may be something like
	ssh -L 5900:localhost:5900 user@pineboard  x11vnc -safer  -localhost -nopw 
-once -auth /tmp/serverauth*   -display :0

If you are doing headless on vnc, get rid of startx on bash profile and just
run it manually.

Test x11vnc with
	x11vnc -display :0

But none of the other flags to start. When in doubt, break the commands down
to make troubleshooting easier.




Using the Breakout Headers
These steps are optional. They were used to include an RTC, so the BBB could
be used as a dashcam.




Device Trees and Pin Initialization
Here are some notes, from my own setup of I2C. It can be confusing if you
are new to the Beagle. This guide is also helpful for configuring other
peripherals such as GPIO, UART, and SPI.
	https://github.com/beagleboard/bb.org-overlays

Follow this link for developers. Ignore the part about pre built kernels if you
used the RCN based installer or image from elinux.org's BeagleBoardDebian.
You already have cape manager support.

If you don't have DTC where is asks for it in the 2nd step for dtc -version,
ignore that step. The ./dtc_overlay.sh script will install the latest
compatible device tree compiler.




Next
	https://github.com/cdsteinkuehler/beaglebone-universal-io

And use this to configure the pins.

There are also preset modes with the pins configured in various states, but
I found it more satisfying to customize them to my needs.
	cd ..
git clone https://github.com/cdsteinkuehler/beaglebone-universal-io
cd beaglebone-universal-io

No installation is required for config-pin.

Test it now:
	./config-pin overlay cape-universal

This will allow a lot of pins to be edited. This must be done first. Then
you can configure pins. There are other modes as well, see github. Cape
-universal exports all pins except for HDMI and EMMC pins.
	#:~/beaglebone-universal-io# cat /sys/devices/platform/bone_capemgr/slots
 0: PF----  -1
 1: PF----  -1
 2: PF----  -1
 3: PF----  -1
 7: P-O-L-  0 Override Board Name, 00A0,Override Manuf, cape-universal

Now you can run something like this:
	./config-pin p8_07 hi

To set Pin 07 on header 8 to GPIO HI

To see more options
	./config-pin -h

e.g.
	./config-pin -l 9_11
default gpio gpio_pu gpio_pd uart

Showing us we can set the pin to UART or one of the GPIO modes.
	./config-pin -a 9_11 uart

Then we can access the UART through either the direct memory registers, or
the linux file system access (search online for more details).

The config-pin overlay cape-universal can be set in /etc/rc.local as well as
individual pin settings.




I2C Usage
	# apt-get install i2c-tools
List
	# i2cdetect -l

The i2c peripheral, after being connected to the BBB, will be on one of the
three i2c buses. Either 0,1, or 2.
# i2cdetect -r 0

Here we search on 0.

I used a BMP180 barometer and mine showed up at 77.

Unfortunately, the sensor can't be read from without a driver. What you will
need to do is recompile the kernel with that driver included, as linux has a
driver for the BMP085, but not by default.

References: (from http://elinux.org/EBC_Exercise_12_I2C) [3] [4]




Recompile Kernel With Sensor Driver
I built the kernel natively on the Beagle, but this failed. It easiest to
cross compile from a Debian based distro. I received an error trying to
cross compile on Gentoo.
	http://elinux.org/EBC_Installing_Kernel_Source

is a good guide that doesn't require javascript (as RCN's docs do). I
installed via the SD card, not through sshfs. Latter did not work. When
searching for the driver, in the kernel compile menu, easiest is to hit "/"
key and search. In my case "/" then BMP returns the place of the barometer
driver.

Finally, with the kernel built with support for your i2c device:
su root
echo bmp085 0x77 > /sys/class/i2c-adapter/i2c-1/new_device

0x77 Can be found from i2c-detect. See references.

These steps are only valid for the bmp pressure sensor, and when it's on i2c
-1. Review dmesg to see if kernel recognized device.
	$ dmesg -T

Navigate to /sys/bus/i2c/drivers/bmp085/1-0077/ and review what the file
system provides access to from the sensor using the newly installed driver.



Instantiate BMP on boot
Two quick user space options:
	echo bmp085 0x77 > /sys/class/i2c-adapter/i2c-2/new_device
in /etc/rc.local. Or add an init.d service (same idea).
References: Elinux.org - BMP on Beaglebone Black Raspberry Pi S.Exchange
Cannot Perform Echo command to load driver for rtc module [5] [6]




Todo





Notes / Errata





Troubleshooting




Installing and updating is slow!

On an SBC a counterfeit SD card could be the cause. A counterfeit or non name
brand SD may take one day, what takes 2 hours to do with a name brand card.




Video monitor flickers, syslog says 
FIFO underflow!
See install steps regarding adjusting memory addresses with devmem2.




How do I disable keypresses for kiosk mode?
I don't have the need, but it's possible to do further lockdown. Look online.




Video is still flickering after 
devmem2 changes!
See my note. More research is needed. I was able to see the BBB running a
~3FPS 720p stream without error at one point, but at a later point, it began to
drop out occasionally. It may be best to either run the viewing feed at a lower
resolution, or to use a more powerful ARM based board (or a desktop if you don't
need low power).




See Also


=======================================================



Desktop SBC Camera Monitor
From: https://wiki.zoneminder.com/Desktop_SBC_Camera_Monitor
This is an continuation of Dedicated SBC Camera Monitor. The tips here are for
a Desktop that will use Firefox to monitor > 1 camera streams at once, but 
otherwise uses the earlier guide. There are some differences.


Contents





How to watch > 6 Monitors

Firefox is the easiest to setup here. It's not known how to configure other 
browsers for > 6 monitors.
	# apt-get install firefox-esr

Then see: Dummies Guide - Notes



How to load firefox in full screen by default
The best add-on for this I've found is mFull. It can be configured to load full
screen, and to remove or autohide the toolbars and navigation bar. There is also
RKiosk but this disables all keys and is not needed in my scenario. I've seen 
some strange behavior with this plugin. On some machines it works and on other 
machines it will not work. Your guess is as good as mine.

Note this addon was used in Firefox 52 or earlier.



I loaded dwm but firefox isn't anywhere?
Sometimes firefox will load on workspace 9 in dwm. Remove all other workspaces 
(config.h, tags) and firefox will load on the first workspace.




What to install from Devuan iso?
You should already know this. Standard system utilities and SSH server. Do not 
install any DE. Do not use automated install which will install DE if you miss 
pressing a button in time.




Shutdown machine automatically?
	# nano /etc/crontab
00 18 * * * root /sbin/poweroff

The problem is you need full path to poweroff or shutdown -h now. If you are on
a separate lan, you may need to use ntp and query some local ntp server, if RTC
is off.




Refresh Screen Periodically? 
Reload every can be set in about:config to reload all new tabs at a specified 
interval (add on). Set new tabs to autoreload. Set interval, then add the 
monitor tab, restart and if done correctly, the tab should refresh periodically.
However, I recommend this guide. 


=======================================================



Dedicated RPI Cam Monitor
From: https://wiki.zoneminder.com/Dedicated_RPI_Camera_Monitor
Following the similar Dedicated_SBC_Camera_Monitor guide, I'll do the same
thing with a Raspberry Pi model 3, and Devuan Ascii, this time (migrated
from Debian Stretch Lite)

This guide is considered an addendum to the above guide, so please be
familiar (at least read through it) first. You will be going back to that
guide, at certain points, to follow those steps. I will not repeat them
here. There is no need.






Start
First, image the Debian Stretch Lite to your SD card.

Boot up and enable ssh (service ssh start), change your password (passwd
pi), and apt-get update && apt-get dist-upgrade If you later want to use
ffmpeg and hwaccel to view streams, you will want to install ffmpeg now from
the official rpi repos (more details further down).

Now we will migrate following these instructions [1] but first read the next
paragraph.

Before installing sysvinit-core I created an /etc/network/interfaces file
with the following:

auto eth0
iface eth0 inet dhcp

Before rebooting, after apt-get install sysvinit-core, make sure /etc/inittab 
exists, and has startup data. I've had issues where, when migrating a VPS to 
devuan Jessie, inittab did not exist, and the VPS would fail to boot.

Continue with the ascii migration guide.

At the end, go to /etc/apt/sources.list.d/ and remove the raspberry pi link
there.

Sidenote: This particular arm OS is armhf (arm with hardware float peripheral 
included). There is also armel, and arm64 (arm with software float, and arm 64 
bit respectively) that is available for debian on the pi.  The devuan sd card 
image for rpi3, if used from the devuan mirrors, is arm64. This is an important
distinction in the case that you might want to use this platform for something 
else. Some apt packages and external software that is available for armhf, are 
not supported (officially supported) as well in arm64, and possibly vice versa.
The main raspberry pi 3 images are armhf, so from that, most software is 
compatible with armhf.


I will try install firefox-esr here. NOTE: it's truly best to use VLC or mplayer
with the hwaccel codecs, and directly view the RTSP stream of the camera, but I
happen to be using this for viewing an internet stream in this use case 
scenario. For those interested in using VLC or mplayer direct with hwaccel 
codecs, please see this thread [2].

Continue following the Dedicated SBC guide, where you install htop, tcpdump,
and git clone the repos for dwm and st. make and install dwm and st
	apt-get remove nfs-common rpcbind avahi-daemon

continue following that guide .xinitrc for your new user will be
#!/bin/bash
export DISPLAY=:0 &
xset s off &
xset -dpms &
/usr/bin/firefox &
exec dwm

And follow the rest of the guide. If everything goes well (as it did for me)
you will be able to reboot and see firefox and dwm startup.




Notes
Note: Firefox starts in workspace 9, so you might have to change over to it
in dwm upon boot. You can remove all workspaces except for #1, and then ff
will boot by default on the first. I tested video (though not sound) and was
able to watch one without any skipping. Those who use ffmpeg and hwaccel may
have even better results.