FreeCalypso > hg > gsm-codec-lib
changeset 109:2361a7d8c1eb
libgsmfrp: randomize grid position params when muting speech,
following GSM 06.11 example solution in more detail
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Mon, 28 Nov 2022 04:15:20 +0000 |
| parents | 3b64f255689a |
| children | 913fe3c11890 |
| files | libgsmfrp/bad_frame.c |
| diffstat | 1 files changed, 12 insertions(+), 0 deletions(-) [+] |
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--- a/libgsmfrp/bad_frame.c Mon Nov 28 04:00:18 2022 +0000 +++ b/libgsmfrp/bad_frame.c Mon Nov 28 04:15:20 2022 +0000 @@ -27,6 +27,17 @@ return mute_flag; } +static void random_grid_pos(struct gsmfr_preproc_state *st, gsm_byte *frame) +{ + unsigned sub, Mc; + + for (sub = 0; sub < 4; sub++) { + Mc = gsmfr_preproc_prng(st, 2); + frame[sub*7+6] &= 0x9F; + frame[sub*7+6] |= Mc << 5; + } +} + void gsmfr_preproc_bfi(struct gsmfr_preproc_state *st, int taf, gsm_byte *frame) { int mute; @@ -42,6 +53,7 @@ case SPEECH_MUTING: mute = reduce_xmaxc(st->speech_frame); memcpy(frame, &st->speech_frame, sizeof(gsm_frame)); + random_grid_pos(st, frame); if (mute) st->rx_state = NO_DATA; return;