FreeCalypso > hg > gsm-codec-lib
annotate doc/AMR-study-utils @ 256:a33edf624061
libgsmfr2: start with API definition and port of libgsmfrp code
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 12 Apr 2024 20:49:53 +0000 |
parents | f4f68c652e98 |
children | e26b974f7ba3 |
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f4f68c652e98
doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
parents:
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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>
parents:
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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>
parents:
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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>
parents:
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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>
parents:
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7 |
f4f68c652e98
doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
parents:
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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>
parents:
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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>
parents:
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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>
parents:
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15 |
f4f68c652e98
doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
parents:
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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>
parents:
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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>
parents:
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18 amr-ietf2cod converts in the opposite direction. |
f4f68c652e98
doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
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19 |
f4f68c652e98
doc: document AMR study utilities
Mychaela Falconia <falcon@freecalypso.org>
parents:
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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>
parents:
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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>
parents:
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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>
parents:
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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>
parents:
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25 in the local machine's native byte order. |