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.

/*
 * This header file contains constant definitions and extern declarations
 * for tables that were originally in qua_gain.tab and qgain475.tab,
 * included in both decoder and encoder modules.
 */

#ifndef	qua_gain_tab_h
#define	qua_gain_tab_h

#include "typedef.h"

/* table used in 'high' rates: MR67 MR74 */
#define VQ_SIZE_HIGHRATES 128

extern const Word16 table_gain_highrates[VQ_SIZE_HIGHRATES*4];

/* table used in 'low' rates: MR475, MR515, MR59 */
#define VQ_SIZE_LOWRATES 64

extern const Word16 table_gain_lowrates[VQ_SIZE_LOWRATES*4];

/* table that was originally in qgain475.tab */

#define MR475_VQ_SIZE 256

extern const Word16 table_gain_MR475[MR475_VQ_SIZE*4];

#endif	/* include guard */