FreeCalypso > hg > gsm-codec-lib
view libgsmfrp/gsm_fr_preproc.h @ 183:452c1d5a6268
libgsmefr BFI w/o data: emit zero output after decoder reset
In real-life usage, each EFR decoder session will most likely begin
with lots of BFI frames before the first real frame arrives. However,
because the spec-defined home state of the decoder is speech rather
than CN, our regular logic for BFI w/o data would have to feed
pseudorandom noise to the decoder (in the "fixed codebook excitation
pulses" part), which is silly to do at the beginning of the decoder
session right out of reset. Therefore, let's check reset_flag_old,
and if we are still in the reset state, simply emit zero output.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Tue, 03 Jan 2023 00:12:18 +0000 |
parents | 2b5770c715ee |
children |
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/* * This header file is the external public interface to libgsmfrp; * it should be installed in the same system include directory * as <gsm.h> from libgsm, on which we depend. */ #ifndef __GSM_FR_PREPROC_H #define __GSM_FR_PREPROC_H #include <gsm.h> struct gsmfr_preproc_state; /* opaque to external users */ extern struct gsmfr_preproc_state *gsmfr_preproc_create(void); /* use standard free() call to free it afterward */ /* reset state to initial */ extern void gsmfr_preproc_reset(struct gsmfr_preproc_state *state); /* main processing functions */ extern void gsmfr_preproc_good_frame(struct gsmfr_preproc_state *state, gsm_byte *frame); extern void gsmfr_preproc_bfi(struct gsmfr_preproc_state *state, int taf, gsm_byte *frame_out); /* utility function */ extern int gsmfr_preproc_sid_classify(const gsm_byte *frame); /* utility datum */ extern const gsm_frame gsmfr_preproc_silence_frame; #endif /* include guard */