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.

/*
 * We implement a couple of helper functions on top of the WAV reader
 * which we've lifted out of opencore-amrnb test code; this header file
 * provides prototype declarations for these functions.
 */

extern int wavrd_check_header(void *wav, const char *filename);
extern int wavrd_get_pcm_block(void *wav, int16_t *pcmbuf);