FreeCalypso > hg > gsm-codec-lib
view libtwamr/lsp.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 | 550d3594c878 |
| 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 : lsp.h * Purpose : Conversion from A(z) to LSP. Quantization and * interpolation of LSPs. * ******************************************************************************** */ #ifndef lsp_h #define lsp_h "$Id $" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "tw_amr.h" #include "typedef.h" #include "q_plsf.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ /* ******************************************************************************** * DEFINITION OF DATA TYPES ******************************************************************************** */ typedef struct { /* Past LSPs */ Word16 lsp_old[M]; Word16 lsp_old_q[M]; /* Quantization state */ Q_plsfState qSt; } lspState; /* ******************************************************************************** * DECLARATION OF PROTOTYPES ******************************************************************************** */ /* ************************************************************************** * * Function : lsp_reset * Purpose : Resets state memory * Returns : 0 on success * ************************************************************************** */ void lsp_reset (lspState *st); /* ************************************************************************** * * Function : lsp * Purpose : Conversion from LP coefficients to LSPs. * Quantization of LSPs. * Description : Generates 2 sets of LSPs from 2 sets of * LP coefficients for mode 12.2. For the other * modes 1 set of LSPs is generated from 1 set of * LP coefficients. These LSPs are quantized with * Matrix/Vector quantization (depending on the mode) * and interpolated for the subframes not yet having * their own LSPs. * ************************************************************************** */ int lsp(lspState *st, /* i/o : State struct */ enum Mode req_mode, /* i : requested coder mode */ enum Mode used_mode, /* i : used coder mode */ Word16 az[], /* i/o : interpolated LP parameters Q12 */ Word16 azQ[], /* o : quantization interpol. LP parameters Q12*/ Word16 lsp_new[], /* o : new lsp vector */ Word16 **anap /* o : analysis parameters */ ); #endif