What Is CBR VBR MBR And What Is Difference Detween Them

CBR VBR MBR

Introduction Of CBR VBR And MBR

When the things comes in terms of configuration of Digital Headend devices then we gets interact with these three encodings named as CBR , VBR and MBR.

These three terms are generally asked in the configuration of encoders. These are called encoding bitrates. Thus there are three types of encoding bitrates CBR , VBR and MBR.

In other words ,

How you stream your video have major impact on quality and bandwidh of video for this only CODEC is not resposible. You need to see how your video stream is handling scene complexity. That is why streaming modes CBR , VBR and MBR came.

What Is CBR

CBR stands for Constant Bitrates. If you want constant bitrate in encoding of video then you need to go for CBR encoding selection. In this option you need to select the constant bitrate for your video it can be 3 Mbps , 5 Mbps or 7 Mbps. If we selected 3 Mbps , by doing so the output bitrate of your video will be constant at 3 Mbps. It will not go more than 3 Mbps and also it will not go less than 3 Mbps.

For a Headend Engineer this CBR is very useful thing. Because he needs to manage the bandwidth of services to avoid the freezing in streams. This option is available in both devices IRDs and Encoders.

As we knows there is limitation of bandwidth in every stream approximately 38 Mbps. So if you want to insert 12 services in this stream then you need to select 3 Mbps CBR per service for smooth running of servies.So the total bandwidth will be 36 Mbps which is in limit. In case if you select VBR mode for 1 or more services then there is chances of freezing in your stream. So the whole services available in the stream will be affected.

To overcome this problem we need to go for CBR.

What Is VBR

VBR stands for Variable Bitrates. As its name indicates that it is giving variable bitrate. So in the output we can get a variable bitrate which can be vary from 2 Mbps to 7 Mbps approximately.

If you want quality in your video then you should go for VBR. Because CBR reduces the information while in VBR it did not reduce the information it gives more bitrate when more information is needed and provides less bitrate when less information is needed. So VBR is better than CBR in terms of quality.

If there is darkness in the video then noise is increased and VBR bitrate increased too much. This is the drawback of VBR.

What Is BER MER

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What Is MBR

MBR stands for Maximum Bitrates. This is the better solution for encoding than CBR and VBR. It is also known as “Cap Of VBR“.

This is the new feature. The MBR’s feature is that it takes good part of CBR and also good part of VBR too.

When it is compared with CBR setting then it reduces bandwidth consumption by 30%-70%. It is done when the scene is simple not complex.

When it is compare with VBR setting then it reduces bandwidth consumption by 20%-50%. This bandwidth is reduces when VBR explodes the bandwidth it generally happens in darkness.

Which One Is Best CBR VBR And MBR

If you want constant bitrate to avoid stream freezing then CBR setting is good for your. In case if you want better picture quality than CBR and you have no issue with bandwidth consumption then you can go for VBR selection.

The drawback of CBR is poor picture quality and the drawback of VBR is high useless bitrate in darkness. If you want to overcome these two drawbacks then you can go for MBR.

MBR selects good part of CBR and also good part of VBR, So selection of MBR is good decision.

Conclusion

CBR VBR and MBR these three terms plays an important role in encoding of video. If complexity of video is not high then you can go for CBR but if its high then you need to go for VBR. Some of the old devices does not support the VBR feature. MBR is is better solution to overcome the problems occurred in CBR VBR, Thus this was all about the CBR VBR and MBR.

Know More About  What is statical Multiplexing

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Comments

  1. Krishnakant says:

    Thank you very much sir, today in this explanation I came to know 3 different things which I didn’t knew before they are drawback of vbr , the new one mbr and the cbr drawback …thanks for the brief explanation…..I would request you to explain something about the future of Indian TV if you won’t mind….

  2. Krishnakant says:

    Also please what are the issues we faces in stb dvb-c and how we can fix it …for the technical support

Comments



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