Sony and Samsung Breaking VBR

By Ethan Ace, Published Oct 21, 2016, 08:30am EDT

For years, users have known variable bitrate (VBR) as one thing only: bandwidth varies, compression stays the same.

This is not an accident but an essential characteristic of VBR. By allowing the bit rate to vary, the compression level can stay the same regardless of the changes in scene complexity (think hallway when a school is closed vs hallway during recess vs hallway at night).

But now, in a confusing move, some manufacturers have changed their definition of VBR, giving users no option to adjust image quality. We take a look at these issues in this note.

Samsung/Hanwha ******* *

*** ******* * ****** (*** *** ****) **** *** ******* a **** *** ************** which ***** *********** ** a ******** ************. ** compression ******* ** ******** in *** *** *********, shown *****, ***** **** Samsung ****** ******** **-** ***** ** *********** levels. ******* **** ******, users **** ****** ** trial *** *****, ********* the ******* *** ** find *** **** ******** of ***** ******* *** bandwidth *** ***** *****.

Sony *** **********

** ****'* *** ********** 4K/20MP ******, *** ***-****** (*** *** ****), *** ***** ******** no ***********/******* ******* ** was ***** ** **** cameras, **** * ***** "Bit **** *" (*********** a ****** *******) *** "Max" (*** ***). 

*******, **** ***** ******** are *********, ** ** found *** ****** ******** less ********* **** *** target ******* ** *** tests, *** ***** ********** the ******* ***, ********** of ***** ********. ** review ***** ****** ** this ***** **** *** tests, *****. 

Why **** ******* 

******* ******* ** ***********, users *** (**********) ****** that ***** ******* *** using ********** *********** ****** (27-30 *******), *** ******* bandwidth. *******, ***** ******* settings ** **** ** the ***** ************* ******* in **** *** ************ (low ***), ***** ******** little ******* ******* ** image *******, *** ********* bandwidth *************.

******* ***** ***** ** these ****** *** ***** workarounds, ***** ***** *********** be ******* *********/******* ***** and ******** ********* ****.

May ** ******

**** **** **** ** highlight *** ************* ***** as *** ******** ** are ***** ** *** our *******. *******, ** you **** ***** ******** of ************* ***** ***** or ***** ***-******** ***** configurations, ******* *****.

Further *******

************* ****** ***/*** (******* bitrate) ************** ** *** to **** ******* ************ video. ******* ****** **** see ***** ******* *** more *********** ** ***** streaming *******, *** ******* of ********* ****, *** compression:

Comments (4)

Sujit Mahapatro

10/22/16 01:48am

Dear Ethan,

I am confused with the terminology MBR used by you, what it means as per standard ?

As such there is

CBR - Constant Bit Rate( Encoder must meet user set target bitrate )

VBR - Variable Bit Rate ( There is no cap on Maximum bitrate to be achieved by encoder, video image quality is the encoder's priority irrespective of result bitrate)

CVBR - Constrained VBR ( Extended VBR standard where there is cap on Maximum Bit Rate, to achieve quality under complex scene encoder can not exceed the Maximum Bit Rate cap).

Do you mean the term MBR is CVBR as per standard ?

https://en.wikipedia.org/wiki/Variable_bitrate

John Honovich

IPVM | In reply to Sujit Mahapatro | 10/22/16 06:55am

Do you mean the term MBR is CVBR as per standard ?

CVBR is not a 'standard'. It is just another name for VBR with a cap.

We avoid using CVBR since, within our industry, some vendors use CVBR to mean something different. For example, Pelco's CVBR implementation historically has been VBR within a tightly constrained bandwidth range.

As such, we use MBR to emphasize the 'maximum' element.

Sujit Mahapatro

In reply to John Honovich | 10/22/16 07:03am

Thanks for the clarification John.

So MBR is the name used by IPVM or some vendors.

Googled about MBR but except IPVM site I couldn't get any such useful information and was curious to know what it is.

Undisclosed #1

IPVMU Certified | In reply to Sujit Mahapatro | 10/22/16 07:12am

Axis is using MBR:

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