FreeCalypso > hg > gsm-codec-lib
view libtwamr/g_adapt.h @ 477:4c9222d95647
libtwamr encoder: always emit frame->mode = mode;
In the original implementation of amr_encode_frame(), the 'mode' member
of the output struct was set to 0xFF if the output frame type is TX_NO_DATA.
This design was made to mimic the mode field (16-bit word) being set to
0xFFFF (or -1) in 3GPP test sequence format - but nothing actually depends
on this struct member being set in any way, and amr_frame_to_tseq()
generates the needed 0xFFFF on its own, based on frame->type being equal
to TX_NO_DATA.
It is simpler and more efficient to always set frame->mode to the actual
encoding mode in amr_encode_frame(), and this new behavior has already
been documented in doc/AMR-library-API description in anticipation of
the present change.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Sat, 18 May 2024 22:30:42 +0000 |
| parents | 2a265be82195 |
| children |
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/* ******************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ******************************************************************************** * * File : g_adapt.h * Purpose : gain adaptation for MR795 gain quantization * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #ifndef g_adapt_h #define g_adapt_h "$Id $" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #define LTPG_MEM_SIZE 5 /* number of stored past LTP coding gains + 1 */ /* ******************************************************************************** * DEFINITION OF DATA TYPES ******************************************************************************** */ typedef struct { Word16 onset; /* onset state, Q0 */ Word16 prev_alpha; /* previous adaptor output, Q15 */ Word16 prev_gc; /* previous code gain, Q1 */ Word16 ltpg_mem[LTPG_MEM_SIZE]; /* LTP coding gain history, Q13 */ /* (ltpg_mem[0] not used for history) */ } GainAdaptState; /* ******************************************************************************** * DECLARATION OF PROTOTYPES ******************************************************************************** */ void gain_adapt_reset (GainAdaptState *st); /* reset of gain adaptor state (i.e. set state memory to zero) returns 0 on success */ /************************************************************************* * * Function: gain_adapt() * Purpose: calculate pitch/codebook gain adaptation factor alpha * (and update the adaptor state) * ************************************************************************** */ void gain_adapt( GainAdaptState *st, /* i : state struct */ Word16 ltpg, /* i : ltp coding gain (log2()), Q */ Word16 gain_cod, /* i : code gain, Q13 */ Word16 *alpha /* o : gain adaptation factor, Q15 */ ); #endif