A Constrained Variable Bit Rate (CVBR) Algorithm for VVenC, an Open VVC Encoder Implementation

Christian R. Helmrich, Senior Member, IEEE, Christian Bartnik, Jens Bran­denburg, Adam Wieckowski, Benjamin Bross, and Detlev Marpe, Fellow, IEEE

The above paper has been accepted for presentation at the IEEE Int. Conf. on Visual Communications and Image Processing (VCIP), Jeju, in December 2023.  This page provides supplementary information on the publication, including more detailed sequence-wise evaluation results.

Please note that there is also a preceding introductory paper on VVenC's rate control algorithm, presented at the IEEE VCIP, Munich in December 2021, on which this publication is based.  That paper and comments thereon are made available here.

An open-source implementation of the XPSNR algorithm is freely available on GitHub:  XPSNR filter plug-in for FFmpeg

Contents:

1. Corrections to the IEEE VCIP published version of the paper as of September 2023

2. Further evaluation results incl. sequence-wise XPSNR, BitErr, and rate outlier data
   
   

1. Corrections to the IEEE VCIP published version of the paper as of September 2023

   Minor details were corrected or clarified.  The first submitted version of the paper is available here:  Paper manuscript
   In the final paper revision, a reference to this supplementary page, containing the additional information requested by the reviewers, was added.
   

   The following information is provided to address the reviewers' comments or requests:

   • Fig. 2: The frame-wise and GOP-wise curves for R_max = 1.5·R_target are faulty. The final paper includes a correct and easier-to-read figure.

   • BitErr: The RC rate accuracy measure, adopted from [1], is defined as follows, where R_actual is the size, in bits, of the resulting bitstream:
                      | R_target – R_actual |
     BitErr  =  ———————  · 100%,       excluding any container data overhead.
                               R_target
     Hence, RC rate matching accuracy is being quantified in percent, and the higher the value of BitErr, the greater the deviation from R_target.

   • The text below Tab. II should read: “the results for the sequence-wise RC ... the noncapped sequence-wise baseline RC are very similar,”

   • Due to space limitations, Tables I and II could not be extended with more rate related data.  Hence, the requested data are provided below.
     
     

2. Further evaluation results incl. sequence-wise XPSNR, BitErr, and rate outlier data

   The following comma separated value (CSV) files contain tables with per-sequence XPSNR [2], BitErr, and maximum (i.e. peak) instantaneous rate measurements (R_i in the paper), with the latter determined GOP-wise using a sliding analysis window of length Intra period  = 1 or 2 GOPs.

   All rate values are tabulated in kilobit/s (kbps), with outliers marked by a !, all XPSNR values are listed in decibel (dB); the tabulator width is 8.

   • GOP-wise RC:  goprc_nomaxrate.csv (R_max = ∞),   goprc_maxrate2x.csv (R_max = 2·R_target),   goprc_maxrate1x.csv (R_max = 1.5·R_target)

   • Sequ.-wise RC:  seqrc_nomaxrate.csv (R_max = ∞),   seqrc_maxrate2x.csv (R_max = 2·R_target),   seqrc_maxrate1x.csv (R_max = 1.5·R_target)

   All videos are 4:2:0 color subsampled and 10 seconds long.  The resolution, frame rate (fps), and bit depth of each video sequence is as follows:

   Class	Name of Sequence	Width	Height	fps	Bit Depth
   UHD  A	Tango4K  FoodMarket  Campfire  CatRobot  DaylightRoad  ParkRunning	4096  3840  3840  3840  3840  3840	2160  2160  2160  2160  2160  2160	60  60  30  60  60  50	10    10    10    10    10    10
   UHD  HHI	BerlinCrossroads  ChestnutTree  March18thSquare  NeptuneFountain  Oberbaum  Quadriga  ReichstagIntoTree  Spree	3840  3840  3840  3840  3840  3840  3840  3840	2160  2160  2160  2160  2160  2160  2160  2160	60  60  60  60  60  60  60  60	10    10    10    10    10    10    10    10
   HD  B	MarketPlace  RitualDance  Cactus  BasketballDrive  BQTerrace	1920  1920  1920  1920  1920	1080  1080  1080  1080  1080	60  60  50  50  60	10    10     8     8     8
   HD  HHI	BerlinCrossroads  ChestnutTree  March18thSquare  NeptuneFountain  Oberbaum  Quadriga  ReichstagIntoTree  Spree	1920  1920  1920  1920  1920  1920  1920  1920	1080  1080  1080  1080  1080  1080  1080  1080	60  60  60  60  60  60  60  60	10    10    10    10    10    10    10    10
   SD  C	BasketballDrill  BQMall  PartyScene  RaceHorses	832   832   832   832	480   480   480   480	50  60  50  30	8     8     8     8
   SD  D	BasketballPass  BQSquare  BlowingBubbles  RaceHorses	416   416   416   416	240   240   240   240	50  60  50  30	8     8     8     8

Please note that the layout or content of this web page may change.  If it does, the date in the following line will be updated.

Christian R. Helmrich, September 30, 2023

References