FreeCalypso > hg > gsm-codec-lib
annotate libtwamr/dhf_subst2.c @ 476:c84bf526c7eb
beginning of libtwamr documentation
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Sat, 18 May 2024 21:22:07 +0000 |
parents | fa0652115168 |
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rev | line source |
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fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 /* |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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2 * The function implemented in this module is an aid for AMR-EFR interworking; |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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3 * it is meant to be invoked directly after amr_encode_frame(). It checks |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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changeset
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4 * the encoder output for MR122 DHF and turns it into EFR DHF just like |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
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5 * amr_dhf_subst_efr(), but only if the input PCM frame was an EHF. This |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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6 * slightly more complicated logic is needed in order to replicate the observed |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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7 * behavior of AMR-EFR speech encoder in the extant GSM network of T-Mobile USA. |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 */ |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
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9 |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 #include "tw_amr.h" |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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11 #include "namespace.h" |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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12 #include "e_homing.h" |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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13 |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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14 void amr_dhf_subst_efr2(struct amr_param_frame *frame, const int16_t *pcm) |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15 { |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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16 if (encoder_homing_frame_test(pcm)) |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 amr_dhf_subst_efr(frame); |
fa0652115168
libtwamr: add amr_dhf_subst_efr2()
Mychaela Falconia <falcon@freecalypso.org>
parents:
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18 } |