FreeCalypso > hg > gsm-codec-lib
changeset 5:4812e00bc100
libgsmfrp: implement handling of good frames
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Sat, 19 Nov 2022 20:46:13 +0000 |
| parents | 286d5f097eb4 |
| children | b2255a5d0519 |
| files | libgsmfrp/Makefile libgsmfrp/good_frame.c |
| diffstat | 2 files changed, 45 insertions(+), 1 deletions(-) [+] |
line wrap: on
line diff
--- a/libgsmfrp/Makefile Sat Nov 19 20:16:09 2022 +0000 +++ b/libgsmfrp/Makefile Sat Nov 19 20:46:13 2022 +0000 @@ -1,6 +1,6 @@ CC= gcc CFLAGS= -O2 -OBJS= comfort_noise.o sidclass.o silence_frame.o state.o +OBJS= comfort_noise.o good_frame.o sidclass.o silence_frame.o state.o LIB= libgsmfrp.a all: ${LIB}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libgsmfrp/good_frame.c Sat Nov 19 20:46:13 2022 +0000 @@ -0,0 +1,44 @@ +/* + * In this module we implement preprocessing of received good frames. + */ + +#include <stdint.h> +#include <string.h> +#include "gsm_fr_preproc.h" +#include "internal.h" + +void gsmfr_preproc_good_frame(struct gsmfr_preproc_state *st, gsm_byte *frame) +{ + int sid; + + /* always set correct magic */ + frame[0] = 0xD0 | frame[0] & 0x0F; + /* now classify by SID */ + sid = gsmfr_preproc_sid_classify(frame); + switch (sid) { + case 0: /* good speech frame */ + memcpy(&st->speech_frame, frame, sizeof(gsm_frame)); + st->rx_state = SPEECH; + return; + case 1: /* invalid SID frame */ + if (st->got_valid_sid) { + st->rx_state = COMFORT_NOISE; + gsmfr_preproc_gen_cn(st, frame); + } else { + st->rx_state = NO_DATA; + memcpy(frame, &gsmfr_preproc_silence_frame, + sizeof(gsm_frame)); + } + return; + case 2: /* valid SID frame */ + st->got_valid_sid = 1; + memcpy(st->sid_prefix, frame, 5); + st->sid_xmaxc[0] = ((frame[6] & 0x1F) << 1) | (frame[7] >> 7); + st->sid_xmaxc[1] = ((frame[13] & 0x1F) << 1) | (frame[14] >> 7); + st->sid_xmaxc[2] = ((frame[20] & 0x1F) << 1) | (frame[21] >> 7); + st->sid_xmaxc[3] = ((frame[27] & 0x1F) << 1) | (frame[28] >> 7); + st->rx_state = COMFORT_NOISE; + gsmfr_preproc_gen_cn(st, frame); + return; + } +}