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frtest: rm gsmfr-hand-test and gsmfr-max-out utils These hack programs were never properly documented and were written only as part of a debug chase, in pursuit of a bug that ultimately turned out to be in our then-hacky patch to osmo-bts-sysmo, before beginning of proper patches in Osmocom. These hack programs need to be dropped from the present sw package because they depend on old libgsm, and we are eliminating that dependency.
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 14 Apr 2024 05:44:47 +0000
parents f4f68c652e98
children e26b974f7ba3
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f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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1 As of this writing (2023-04), the main emphasis here at Themyscira Wireless is
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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2 on classic FR and EFR codecs, particularly the latter, rather than AMR.
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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3 However, given the close relation between GSM EFR and the highest MR122 mode of
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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4 AMR, we are starting to explore AMR a little too, focusing on the reference C
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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5 implementation and various published test sequences. Working in this direction,
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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6 we have developed the following AMR study and exploration utilities:
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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8 amr-cod-parse This utility reads the *.cod binary file format used by 3GPP
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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9 reference code and test sequences for AMR-encoded speech, groks
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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10 every frame and dumps all recorded parameters in human-readable
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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11 form.
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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12
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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13 amr-ietf-parse A similar AMR parse/dump utility to amr-cod-parse, but reading
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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14 the more common IETF RFC 4867 *.amr binary file format instead.
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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16 amr-cod2ietf These two utilities convert between 3GPP *.cod and IETF *.amr
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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17 amr-ietf2cod formats. amr-cod2ietf converts from *.cod to *.amr;
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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18 amr-ietf2cod converts in the opposite direction.
f4f68c652e98 doc: document AMR study utilities
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19
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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20 Just like ETSI *.cod and *.dec formats for EFR, 3GPP *.cod format for AMR is
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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21 endian-dependent. Our amr-cod-parse and amr-cod2ietf utilities expect LE byte
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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22 order by default, matching the official test sequences in
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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23 ts_126074v170001p0.zip; they also support BE byte order with -b option.
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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24 However, our amr-ietf2cod utility (rarely needed) emits its cod-format output
f4f68c652e98 doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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25 in the local machine's native byte order.