(Continuation of part of Questions 22/16 and 19/16)
Background and justification
In the scope of signal processing, in particular in relationship with the
definition of new schemes, SG 16 recognized the need to investigate and specify
appropriate software tools for the verification and evaluation of signal
processing algorithms. Past results include Recommendation G.191, which gives
some basic principles for the use of this kind of tools and a list of the
recommended tools available from the ITU-T Software Tool Library.
Cases which will greatly benefit from the existence of standardized software
a) situations where experimental results generated with different
software tools may not be directly compared;
b) software tools used by different organizations may not perfectly
conform to related ITU-T Recommendations, which may delay ITU-T
c) ITU-T Recommendations may leave open room for different
d) frequently software tools which are not specified by ITU-T
Recommendations are necessary in the standardization process of signal
e) the ability to perform host laboratory processing activities (which
are part of the testing activities in the standardization process of speech
coders) completely in software, thus significantly reducing cost and time to
perform such activities and at the same time increasing their reliability
Additionally, ITU-T has published several voice coding Recommendations, such
as G.728 describing a 9.6, 11.2, 16 and 40 kbit/s speech coding algorithm, G.729
describing a 6.4, 8 and 11.8 kbit/s speech coding algorithm, and G.723.1
describing a dual rate speech coding algorithm at 5.3 and 6.3 kbit/s. There is
therefore the need for a clearly identified point-of-contact for maintenance of
such Recommendations (e.g. for the correction of specification defects and the
incorporation of algorithm extensions), in particular Recommendations that have
been specified with ANSI C code.
- What software tools for the signal processing standardization
activities should be specified, taking into account the increasing complexity
of signal processing standards and the need for compatible test methods?
- Tool Library: definition of methodology to collect, evaluate,
qualify, maintain, archive and make available unique implementation and
documentation of the software tools.
- Selection of Tools: identification of software tools that should be
included in the Tool Library.
- Requirements and Objectives: definition of the Requirements and
Objectives for the performance of each tool.
- Tool Structure: identification of the proper structure for the
software tools (documentation, input and output, storage, etc.) to allow
their proper interworking.
- Maintenance: collection of defect reports on voice coding
Recommendations, assessment on their merit, and identification of the
appropriate course of action. This may include generation of "Implementor's
Guides", corrigenda or re-issuance of existing Recommendations.
- Maintain the existing ITU-T Software Tool Library and existing voice
coding Recommendations, in particular (continuous activity):
- G.711, G.726, and G.727;
- G.728 and its annexes;
- G.729 and its annexes;
- G.723.1 and its annexes;
- G.722 and G.722.1 and its annexes.
- Identify and implement new algorithms to upgrade the ITU-T Software
Tool Library as support to ITU-T signal processing activities by the year
- signal processing framework tool;
- basic operators;
- echo cancellation models;
- channel models, error patterns and statistics for packet-based
networks (including IP and Internet), wireless networks and mobile-satellite
- identify techniques for verification of the correct implementation of
- Other SG 16 questions as relevant.
- ITU-T SG 12 for performance, the work on the P-series of
Recommendations, for changes that may affect the Tools Library.
- ITU-R SG 8, 3GPP and 3GPP-2 on channel models.