Organisation internationale de normalisation

Discussions in final plenary

The Audio Chair presented text that described a process that audio experts could use to develop a reference-quality USAC Reference Source Code encoder.

Schuyler Quackenbush, Audio Research Labs, expressed the following point of view on this topic:

At the 86^th MPEG meeting the following reference source code will be available for the Unified Speech and Audio Coding work:

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  Normative reference source code for the decoding process.
  
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  Informative reference source code for the encoding process. Encoder source code need only produce a bitstream that is consistent with the normative decoder bitstream syntax.
  

Subsequent to the 86^th meeting, audio experts can use the encoder source as a foundation for an open and cooperative software development project in which source code modules from HE-AAC V2, AMR-WB+ and RM0 normative decoder source code are incorporated into the Encoder reference source code.

Typically, in current practice, CE modules under test are incorporated into the RM0 proponent encoder via object-modules conforming to an agreed-upon API.

The process outlined above for creating USAC encoder reference software can result in the USAC reference software encoder being as good as or better than the RM0 proponent encoder.

Experts from Huawei, Ericsson, Nokia, LG, France Telecom R&D, Qualcomm and Polycom, expressed the following point of view on this topic:

In order to facilitate the integration of relevant technologies in Core experiments, they should be conducted on a single reference source code for both encoder and decoder that is made available for each interested party in the MPEG audio subgroup. This reference code should be of sufficient quality and available before the start of the core experiment process. The encoder code should have the following characteristics:

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  Part of the encoder code should be made available (e,.g. signal path, MDCT, CELP parts)
  
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  Parts which are felts sensitive by the proponents of the RM0 could be delivered as libraries with the appropriate API and kept up to date with the latest Reference Model.
  
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  The binary modules could be replaced by source code if felt appropriate.
  

The Audio Chair notes that there are WG11 documents that define the CE process and hence CE work can commence at the 86^th meeting.