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/* -*- c++ -*- */
/*
* Copyright 2008 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
// This file stores all the RIFF file type knowledge for the gr_wavfile_*
// blocks.
#include <cstdio>
/*!
* \brief Read signal information from a given WAV file.
*
* \p fp File pointer to an opened, empty file.
* \p sample_rate Stores the sample rate [S/s]
* \p nchans Number of channels
* \p bytes_per_sample Bytes per sample, can either be 1 or 2 (corresponding to
* 8 or 16 bit samples, respectively)
* \p first_sample_pos Number of the first byte containing a sample. Use this
* with fseek() to jump from the end of the file to the first sample
* when in repeat mode.
* \p samples_per_chan Number of samples per channel
* \p normalize_fac The normalization factor with which you need to divide the
* integer values of the samples to get them within [-1;1]
* \p normalize_shift The value by which the sample values need to be shifted
* after normalization (reason being, 8-bit WAV files store samples as
* unsigned char and 16-bit as signed short int)
* \return True on a successful read, false if the file could not be read or is
* not a valid WAV file.
*/
bool
gri_wavheader_parse(FILE *fp,
unsigned int &sample_rate,
int &nchans,
int &bytes_per_sample,
int &first_sample_pos,
unsigned int &samples_per_chan);
/*!
* \brief Read one sample from an open WAV file at the current position.
*
* Takes care of endianness.
*/
short int
gri_wav_read_sample(FILE *fp, int bytes_per_sample);
/*!
* \brief Write a valid RIFF file header
*
* Note: Some header values are kept blank because they're usually not known
* a-priori (file and chunk lengths). Use gri_wavheader_complete() to fill
* these in.
*/
bool
gri_wavheader_write(FILE *fp,
unsigned int sample_rate,
int nchans,
int bytes_per_sample);
/*!
* \brief Write one sample to an open WAV file at the current position.
*
* Takes care of endianness.
*/
void
gri_wav_write_sample(FILE *fp, short int sample, int bytes_per_sample);
/*!
* \brief Complete a WAV header
*
* Note: The stream position is changed during this function. If anything
* needs to be written to the WAV file after calling this function (which
* shouldn't happen), you need to fseek() to the end of the file (or
* whereever).
*
* \p fp File pointer to an open WAV file with a blank header
* \p byte_count Length of all samples written to the file in bytes.
*/
bool
gri_wavheader_complete(FILE *fp, unsigned int byte_count);
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