FreeCalypso > hg > gsm-codec-lib
view libtest/wavwriter.c @ 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> |
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date | Tue, 03 Jan 2023 00:12:18 +0000 |
parents | 634df6435e16 |
children |
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/* ------------------------------------------------------------------ * Copyright (C) 2009 Martin Storsjo * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. * See the License for the specific language governing permissions * and limitations under the License. * ------------------------------------------------------------------- */ #include "wavwriter.h" #include <stdio.h> #include <string.h> #include <stdlib.h> #include <stdint.h> struct wav_writer { FILE *wav; int data_length; int sample_rate; int bits_per_sample; int channels; }; static void write_string(struct wav_writer* ww, const char *str) { fputc(str[0], ww->wav); fputc(str[1], ww->wav); fputc(str[2], ww->wav); fputc(str[3], ww->wav); } static void write_int32(struct wav_writer* ww, int value) { fputc((value >> 0) & 0xff, ww->wav); fputc((value >> 8) & 0xff, ww->wav); fputc((value >> 16) & 0xff, ww->wav); fputc((value >> 24) & 0xff, ww->wav); } static void write_int16(struct wav_writer* ww, int value) { fputc((value >> 0) & 0xff, ww->wav); fputc((value >> 8) & 0xff, ww->wav); } static void write_header(struct wav_writer* ww, int length) { int bytes_per_frame, bytes_per_sec; write_string(ww, "RIFF"); write_int32(ww, 4 + 8 + 16 + 8 + length); write_string(ww, "WAVE"); write_string(ww, "fmt "); write_int32(ww, 16); bytes_per_frame = ww->bits_per_sample/8*ww->channels; bytes_per_sec = bytes_per_frame*ww->sample_rate; write_int16(ww, 1); // Format write_int16(ww, ww->channels); // Channels write_int32(ww, ww->sample_rate); // Samplerate write_int32(ww, bytes_per_sec); // Bytes per sec write_int16(ww, bytes_per_frame); // Bytes per frame write_int16(ww, ww->bits_per_sample); // Bits per sample write_string(ww, "data"); write_int32(ww, length); } void* wav_write_open(const char *filename, int sample_rate, int bits_per_sample, int channels) { struct wav_writer* ww = (struct wav_writer*) malloc(sizeof(*ww)); memset(ww, 0, sizeof(*ww)); ww->wav = fopen(filename, "wb"); if (ww->wav == NULL) { free(ww); return NULL; } ww->data_length = 0; ww->sample_rate = sample_rate; ww->bits_per_sample = bits_per_sample; ww->channels = channels; write_header(ww, ww->data_length); return ww; } void wav_write_close(void* obj) { struct wav_writer* ww = (struct wav_writer*) obj; if (ww->wav == NULL) { free(ww); return; } fseek(ww->wav, 0, SEEK_SET); write_header(ww, ww->data_length); fclose(ww->wav); free(ww); } void wav_write_data(void* obj, const unsigned char* data, int length) { struct wav_writer* ww = (struct wav_writer*) obj; if (ww->wav == NULL) return; fwrite(data, length, 1, ww->wav); ww->data_length += length; }