Axis Fixes VBR / CBR Setting

By: Ethan Ace, Published on Feb 23, 2015

Bit rate control is an important element in transmitting surveillance video. The three most common options as explained in our CBR vs VBR: Surveillance Streaming Guide are:

  • VBR - variable bit rate
  • CBR - constant bit rate
  • VBR with a cap - variable bit rate with a maximum bit rate level

Historically, Axis settings here have been misleading. Now, new firmware (5.60) has fixed this. In this note, we explain what changes they have made and what this means.

*** **** ******* ** an ********* ******* ** transmitting ************ *****. *** three **** ****** ******* as ********* ** ****** ** ***: ************ Streaming ********:

  • *** - ******** *** rate
  • *** - ******** *** rate
  • *** **** * *** - ******** *** **** with * ******* *** rate *****

************, **** ******** **** have **** **********. ***, new ******** (*.**) *** fixed ****. ** **** note, ** ******* **** changes **** **** **** and **** **** *****.

[***************]

Axis '***'

**** *** ************* ****** its *** **** * cap ******* "******** *** rate" ** ***** ** the ***** ***** **** a ****** ******* ******** 5.21:

**** **** **** ******* that **** ******** ********* CBR *** *** *** with * ***, ***** was ******. *** "****** bit ****" ******* **** when ** "***" **** actually **** ** * cap, **** ******** **** rising ** **** ***** if ********* ***** ** scene **********.

New **** *** *** ****

***** ***** ** **** confusing ********, **** ******* the ******** **** ** camera ***** ********** *.** (.*** ******* notes), **** "********" ** "maximum" *** ****, **** here:

******* *** **** **** functions **** ** ******** bit **** ***. *******, this ******** ** **** more *****, **** ** line **** *** **** of *** ********, *** may ***** ********* ** new *****.

**** **** **** ******* do *** **** * constant *** **** **** at ***, **** ***, either ****** ** ********.

Using '***' ** *** **** * ***

**** ******** ********** ***** VBR **** * *** bit **** ******** ********. **** allows ********* ** ****** low **** ****** *** less *******, **** ** daytime ** ******** *****, but ** *** ******** as ****** ** ****** complexity ******, *.*., ********* or **** *************.

***** *** ****** *** increase *********** ** ***** to **** ********* ****** its ***, **** ********* in ****** ** *****, with ****** ********* ******. Readers *** *** *** ******: ******** ********* ** Night ** **** ****** *** **** *******.

Comments (12)

Interesting, I tried to get them to change the word "constant" to the proper "constrained" for 6 years with no luck.

Thanks Ethan, for sharing the information.

it seems there are two VBRs ?

1. VBR no Rmax cap

2. VBR with Rmax cap

No CBR setting?

-Ling

Axis does not support traditional CBR, e.g., set the bitrate to 5Mb/s regardless of what the scene, resolution, frame rate, compression, etc. is.

That makes sense to me, given that maximum is simply better than constant.

Thanks John. For big Metro and Enterprise applications, the MBR (VBR + CAP) rate control is essential.

Btw, I think MBR would be a good term to adopt. A 3 letter acronym makes it a clearer contrast to VBR and CBR. CBR is constant, VBR varies and MBR varies to a maximum bit rate.

The old CBR settings were critical to manage "runaway" bandwidths with some network cameras at night. I think IPVM did one of the first studies on this and validated what we've observed for years. A 720P or 1080P camera that could manage on 2 to 4 Mbps during the day, could drive 10 to 15 Mbps bandwidth at night. The CBR settings, effecting a cap at say 5 mbps, with priority on quality, should really be a default. Thanks for the info. Hadn't seen this in the new firmware yet.

Brad, yes, and here is the most recent test report showing runaway night bandwidth: Tested: Lowering Bandwidth at Night is Good

Note, the new setting works the same, it just now is clearer and stops people from believing that Axis has a true CBR, which did not have previously either, despite labelling it constant.

After years of this confusing verbiage, Axis changed the language used in camera setup in firmware 5.60 (.pdf release notes), from "constant" to "maximum" bit rate, seen here:

I am unable to find the mention of that verbiage change in the release notes you linked, nor in the detailed notes of either of the 5.60.x firmware releases for the P3364.

How did you discover it?

Curiously, in the 5.60.1 notes mention is made of a change in the behavior of CBR:

Improved Constant Bitrate Control, the Constant Bit Rate (CBR) will now adjust to target bit rate quicker.

What does that mean, if 'constant' now equals 'maximum'?

I found alluded to in the Axis Latency whitepaper, which the spider picked up.

Wow, they are a bit conflused about this change. The paragraphs below are duplicated word for word in this manual, except for changing Constant to Maximum.

I heard previously from a sytem integrator that Axis' 'CBR' (VBR with a limit) was good at limiting bandwidth, however the SI was not so happy when his customer complained that they lost frames in the recordings of an incident. Turns out that to maintain the bandwidth limit, the codec was dropping frames. This is Ok if you know what's going on but the customer was surprised and complained that his requirement of x fps was not maintained. In some applications a specified fps (or minimum fps) is a legal requirement in Europe. Is that also the case in the US?

"I heard previously from a system integrator that Axis' 'CBR' (VBR with a limit) was good at limiting bandwidth, however the SI was not so happy when his customer complained that they lost frames in the recordings of an incident."

That's the integrator's mistake.

By default, Axis is set to true VBR (i.e., goes as high as it needs). So either the integrator's techs set the 'CBR' level too low or someone from the customer mucked with the settings. It's not an Axis issue.

Yes, if you sets the max bitrate too low for one's needs, either frames are going to be dropped or compression is going to be increased to compensate (see the priority option in the Axis configuration screen).

Login to read this IPVM report.
Why do I need to log in?
IPVM conducts unique testing and research funded by member's payments enabling us to offer the most independent, accurate and in-depth information.

Related Reports

Bandwidth Fundamentals For Video Surveillance on Jan 13, 2020
Bandwidth is the most fundamental element of computer networking for video surveillance systems. Because video surveillance can consume an immense...
Testing Bandwidth vs. Frame Rate on Jan 23, 2019
Selecting frame rate has a major impact on surveillance bandwidth and storage consumption. But with smart codecs now common and cameras more...
Bandwidth vs Low Light Shootout - Avigilon, Axis, Bosch, Dahua, Geovision, Hanwha, Hikvision, Uniview, Vivotek on Feb 08, 2019
Nighttime bandwidth spikes are a major concern in video surveillance, but do all manufacturers' cameras perform the same? Are some more consistent...
H.265 Usage Statistics on Apr 19, 2019
H.265 has been available in IP cameras for more than 5 years and, in the past few years, the number of manufacturers supporting this codec has...
Manufacturer Favorability Guide 2019 on Jun 12, 2019
The 259 page PDF guide may be downloaded inside by all IPVM members. It includes our manufacturer favorability rankings and individual...
Average Frame Rate Video Surveillance 2019 on May 23, 2019
What is the average frame rated used in video surveillance systems? In IPVM's 2011 statistics, the average was 6-8fps increasing to ~10fps in...
Verkada Video Quality Problems Tested on May 23, 2019
Verkada suffers from numerous video quality problems, not found in commercial IP cameras, new IPVM testing of Verkada vs Axis and Hikvision...
Smart CODEC Usage Statistics 2019 on Jun 03, 2019
Smart codecs are now nearly a standard feature in IP cameras, but our statistics show integrator adoption has not increased at the same rate. In...
False Verkada 'Unrivaled' Low Light Performance Claim Removed on Jun 12, 2019
Verkada falsely claimed that it delivered 'UNRIVALED LOW LIGHT PERFORMANCE' until IPVM questioned. In fact, Verkada's low light performance is...
Axis Live Privacy Shield Analytics Tested on Jun 25, 2019
Privacy is becoming a bigger factor in video surveillance, driven both by increased public awareness and by GDPR. Now, Axis has released Live...

Most Recent Industry Reports

Intersec 2020 Final Show Report on Jan 21, 2020
IPVM spent all 3 days at the Intersec 2020 show interviewing various companies and finding key trends. We cover: Middle East Enterprise...
Vehicle & Long Range Access Reader Tutorial on Jan 21, 2020
One of the classic challenges for access control are parking lots and garages, where the user's credential is far from the reader. With modern...
Clearview AI Alarm - NY Times Report Says "Might End Privacy" on Jan 20, 2020
Over the weekend, the NY Times released a report titled "The Secretive Company That Might End Privacy as We Know It" about a company named...
Favorite Camera Manufacturers 2020 on Jan 20, 2020
The past 2 years of US bans and sanctions have shaken the video surveillance industry but what impact would this have on integrators' favorite...
"Severely Impacted" Mercury Security 2020 Leap Year Firmware Issue on Jan 17, 2020
One of the largest access controller manufacturers has a big problem: February 29th. Mercury Security, owned by HID, is alerting partners of the...
Apple Acquires XNOR.ai, Loss For The Industry on Jan 16, 2020
Apple has acquired XNOR.ai for $200 million, reports GeekWire. This is a loss for the video surveillance industry. XNOR.ai stunned the industry...
Installation Course January 2020 - Last Chance on Jan 16, 2020
Thursday, January 16th is your last chance to register for the Winter 2020 Video Surveillance Installation Course. This is a unique installation...
Halo Smart Vape Detector Tested on Jan 16, 2020
The Halo Smart Sensor claims to detect vaping, including popular brand Juul and even THC vapes. But how well does it work in real world...
PRC Government Entity Now Controlling Shareholder of Infinova / March Networks on Jan 16, 2020
A PRC government entity is now the controlling shareholder of US security manufacturer Infinova as well as its wholly-owned subsidiary March...
Network Cabling for Video Surveillance on Jan 15, 2020
In this guide, we explain the fundamentals of network cabling for video surveillance networks, how they should be installed, and the differences in...