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.

/*-----------------------------------------------------*
 | Table for routine Pow2().                           |
 -----------------------------------------------------*/

static const Word16 table[33] =
{
    16384, 16743, 17109, 17484, 17867, 18258, 18658, 19066, 19484, 19911,
    20347, 20792, 21247, 21713, 22188, 22674, 23170, 23678, 24196, 24726,
    25268, 25821, 26386, 26964, 27554, 28158, 28774, 29405, 30048, 30706,
    31379, 32066, 32767
};