
Hybrid Audio Call Feb. 20 2012

Participants:

Savvas, Chulhee, Jens, Silvio, Anna, Roland, Matthias, Chris



Audio Call
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Discussion about HRCs:

* opticom test vector: transcoding, second encoding has 5 times higher bitrate than the first one, is this realistic?

* In the encrypted case, the model cannot access the information about the transmitted resolution in the bitstream.
  Thus, should the transmitted resolution be available to the model as additional parameter?


After a lot of discussion, the following agreement was reached:

In general, HRC should be 'realistic', and in particular:

-->  realistic condition for transcoding: the ratio of the bitrate of the first encoding to the second encoding must not be smaller than 1:2.5

-->  realistic condition for down-up scaling: "down-upscaling (i.e. down-scaling of a video, transmission of the down-scaled video and up-scaling of
  the video after transmission for play-back) is allowed only if it leads to equal or better quality over the transmission of the video at the same bitrate 
  keeping the resolution constant."
  E.g. transmission of a VGA video by down-scaling to QVGA, transmission of the QVGA video at bitrate b and up-scaled play-back at VGA resolution, 
  is allowed if the quality is equal or superior to the transmission of the same video at bitrate b and constant resolution VGA.



* should the submitted model exe be 32bit or 64bit?
  
--> both versions should be allowed. (no ILG present in audio call, though)


* submission procedure:
  executable + if desired submit encrypted source code to ILG until end of April
  model checking will be done on a small set of test vectors

  Q: Who is the person of contact to submit the model to?

  Chulhee will contact ILG to ask if procedure below is OK, and will ask for the person of contact for model submission.

  ______________________________________________________________________________

  first submission deadline: April 30
  final submission deadline: May 21 but if ILG cannot validate first model
  by May 14, the final submission deadline will be shifted accordingly.
  ______________________________________________________________________________


The model submission procedure is according to the procedure used in the HDTV project:

All proponents must submit the first version all models by end of April.

The ILG will validate each submitted model by the initial submission date.
The ILG will validate that each submitted model runs on their computer, by running the model on the test vectors, and showing that the model outputs 
the VQR expected by the proponent. If necessary, a different ILG may be asked to validate the proponents model (e.g., if another ILG has a computer 
that may have an easier time running the model.)  

Each ILG will try to validate the first submitted version of a model by May 14 latest. If this is not possible the final submission deadline will be
shifted accordingly.

All proponents have the option of submitting updated models up to the model submission deadline May 21 2012.  
Such model updates may be either: 
(1) Intended to make the model run on the ILGs computer.  
(2) Model improvements, intended to replace the previous model submitted. Such improved models will be checked as time permits.
If the replacement model runs on the ILG computer, it will replace the previous submission.  If the replacement model is not able to run on the ILG 
computer within one week, the previous submission will be used. 
ILG checks on models may exceed the model submission deadline.  ILG request that proponents try to limit this to one replacement model, so that the 
ILG are not asked to validate an excessive number of models. 

  
  

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* next audio call: Thursday April 26 15:00CET      *
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