FreeCalypso > hg > gsm-codec-lib
view amrconv/amr_defs.h @ 581:e2d5cad04cbf
libgsmhr1 RxFE: store CN R0+LPC separately from speech
In the original GSM 06.06 code the ECU for speech mode is entirely
separate from the CN generator, maintaining separate state. (The
main intertie between them is the speech vs CN state variable,
distinguishing between speech and CN BFIs, in addition to the
CN-specific function of distinguishing between initial and update
SIDs.)
In the present RxFE implementation I initially thought that we could
use the same saved_frame buffer for both ECU and CN, overwriting
just the first 4 params (R0 and LPC) when a valid SID comes in.
However, I now realize it was a bad idea: the original code has a
corner case (long sequence of speech-mode BFIs to put the ECU in
state 6, then SID and CN-mode BFIs, then a good speech frame) that
would be broken by that buffer reuse approach. We could eliminate
this corner case by resetting the ECU state when passing through
a CN insertion period, but doing so would needlessly increase
the behavioral diffs between GSM 06.06 and our version.
Solution: use a separate CN-specific buffer for CN R0+LPC parameters,
and match the behavior of GSM 06.06 code in this regard.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Thu, 13 Feb 2025 10:02:45 +0000 |
parents | 934cf92a1c45 |
children |
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/* * This header file holds some miscellaneous definitions for AMR, * to be used by parsing and conversion debug utilities. */ #define MAX_PRM_SIZE 57 /* max. num. of params */ #define MAX_SERIAL_SIZE 244 /* max. num. of serial bits */ #define MAX_IF1_BYTES 31 /* max bytes in AMR IF1 packing */ #define IETF_HDR_LEN 6 /* .amr file header bytes */ enum TXFrameType { TX_SPEECH_GOOD = 0, TX_SID_FIRST, TX_SID_UPDATE, TX_NO_DATA, TX_SPEECH_DEGRADED, TX_SPEECH_BAD, TX_SID_BAD, TX_ONSET, TX_N_FRAMETYPES /* number of frame types */ }; enum Mode { MR475 = 0, MR515, MR59, MR67, MR74, MR795, MR102, MR122, MRDTX }; #define MODE_NO_DATA 15 /* number of speech bits for all modes */ #define AMR_NBITS_475 95 #define AMR_NBITS_515 103 #define AMR_NBITS_59 118 #define AMR_NBITS_67 134 #define AMR_NBITS_74 148 #define AMR_NBITS_795 159 #define AMR_NBITS_102 204 #define AMR_NBITS_122 244 #define AMR_NBITS_SID 35 /* number of distinct parameters for all modes */ #define PRMNO_MR475 17 #define PRMNO_MR515 19 #define PRMNO_MR59 19 #define PRMNO_MR67 19 #define PRMNO_MR74 19 #define PRMNO_MR795 23 #define PRMNO_MR102 39 #define PRMNO_MR122 57 #define PRMNO_MRDTX 5 /* ETSI/3GPP test sequence file format */ #define COD_FORMAT_NWORDS 250