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Video buffering verifier

The Video Buffering Verifier (VBV) is a theoretical MPEG video buffer model, used to ensure that an encoded video stream can be correctly buffered, and played back at the decoder device.

By definition, the VBV shall not overflow nor underflow when its input is a compliant stream, (except in the case of low_delay). It is therefore important when encoding such a stream that it comply with the VBV requirements.

One way to think of the VBV is to consider both a maximum bitrate and a maximum buffer size. You'll need to know how quickly the video data is coming into the buffer. Keep in mind that video data is always changing the bitrate so there is no constant number to note how fast the data is arriving. The larger question is how long before the buffer overflows. A larger buffer size simply means that the decoder will tolerate high bitrates for longer periods of time, but no buffer is infinite, so eventually even a large buffer will overflow.

Operation Modes edit

There are two operational modes of VBV: Constant Bit Rate (CBR) and Variable Bit Rate (VBR). In CBR, the decoder's buffer is filled over time at a constant data rate. In VBR, the buffer is filled at a non-constant rate. In both cases, data is removed from the buffer in varying chunks, depending on the actual size of the coded frames.

Standards edit

In the H.264 and VC-1 standards, the VBV is replaced with generalized version called Hypothetical Reference Decoder (HRD).

References edit

  • MPEG Tutorial - Video Buffering Verifier

video, buffering, verifier, this, article, multiple, issues, please, help, improve, discuss, these, issues, talk, page, learn, when, remove, these, template, messages, this, article, relies, largely, entirely, single, source, relevant, discussion, found, talk,. This article has multiple issues Please help improve it or discuss these issues on the talk page Learn how and when to remove these template messages This article relies largely or entirely on a single source Relevant discussion may be found on the talk page Please help improve this article by introducing citations to additional sources Find sources Video buffering verifier news newspapers books scholar JSTOR November 2019 This article includes a list of references related reading or external links but its sources remain unclear because it lacks inline citations Please help improve this article by introducing more precise citations November 2019 Learn how and when to remove this message Learn how and when to remove this message The Video Buffering Verifier VBV is a theoretical MPEG video buffer model used to ensure that an encoded video stream can be correctly buffered and played back at the decoder device By definition the VBV shall not overflow nor underflow when its input is a compliant stream except in the case of low delay It is therefore important when encoding such a stream that it comply with the VBV requirements One way to think of the VBV is to consider both a maximum bitrate and a maximum buffer size You ll need to know how quickly the video data is coming into the buffer Keep in mind that video data is always changing the bitrate so there is no constant number to note how fast the data is arriving The larger question is how long before the buffer overflows A larger buffer size simply means that the decoder will tolerate high bitrates for longer periods of time but no buffer is infinite so eventually even a large buffer will overflow Operation Modes editThere are two operational modes of VBV Constant Bit Rate CBR and Variable Bit Rate VBR In CBR the decoder s buffer is filled over time at a constant data rate In VBR the buffer is filled at a non constant rate In both cases data is removed from the buffer in varying chunks depending on the actual size of the coded frames Standards editIn the H 264 and VC 1 standards the VBV is replaced with generalized version called Hypothetical Reference Decoder HRD References editMPEG Tutorial Video Buffering Verifier nbsp This computing article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Video buffering verifier amp oldid 1070490181, wikipedia, wiki, book, books, library,

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