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comparison doc/EFR-rationale @ 127:4af99bf8671a

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doc/EFR-rationale: add future roadmap section
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 11 Dec 2022 03:25:21 +0000
parents b33f2168fdec
children 3a0ee08a3b9d
comparison
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126:6fd49f73b025 127:4af99bf8671a
78 librified derivative of ETSI EFR code. The problem of global vars has been 78 librified derivative of ETSI EFR code. The problem of global vars has been
79 solved in this library version - they've been gathered into one unified struct 79 solved in this library version - they've been gathered into one unified struct
80 for encoder state and another unified struct for decoder state - but the problem 80 for encoder state and another unified struct for decoder state - but the problem
81 of poor performance (significantly worse than opencore-amrnb) still remains for 81 of poor performance (significantly worse than opencore-amrnb) still remains for
82 now. 82 now.
83
84 Future roadmap
85 ==============
86
87 If someone is implementing a DSP vocoder block for a GSM MS or a network-side
88 speech transcoder that needs to support all standard GSM codecs, at some point
89 they will need to implement both EFR and AMR. Given the close relation between
90 these two codecs (they are not perfectly compatible as we started out saying,
91 but they are still very closely related), keeping two entirely separate library
92 implementations for AMR and EFR will be very inefficient in the long run, and a
93 nightmare to get them to perform equally well. It seems to me (Mother Mychaela)
94 that the correct solution will be to produce a single codec library that
95 implements both AMR and EFR, probably by starting with an AMR library and
96 extending it with special modes to handle those aspects where EFR differs. It
97 is my forecast that we are going to end up doing something along these lines in
98 Themyscira - but it will be much later down the road; for the time being, our
99 initial version of ThemWi will only support FR and EFR, but not AMR.