gr_wavfile_sink.cc

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/* -*- c++ -*- */
/*
 * Copyright 2004,2006,2007,2008 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <gr_wavfile_sink.h>
#include <gr_io_signature.h>
#include <gri_wavfile.h>
#include <stdexcept>
#include <climits>
#include <cstring>
#include <cmath>
#include <fcntl.h>

// win32 (mingw/msvc) specific
#ifdef HAVE_IO_H
#include <io.h>
#endif
#ifdef O_BINARY
#define OUR_O_BINARY O_BINARY
#else
#define OUR_O_BINARY 0
#endif

// should be handled via configure
#ifdef O_LARGEFILE
#define OUR_O_LARGEFILE O_LARGEFILE
#else
#define OUR_O_LARGEFILE 0
#endif


gr_wavfile_sink_sptr
gr_make_wavfile_sink(const char *filename,
		     int n_channels,
		     unsigned int sample_rate,
		     int bits_per_sample)
{
  return gr_wavfile_sink_sptr (new gr_wavfile_sink (filename,
						    n_channels,
						    sample_rate,
						    bits_per_sample));
}

gr_wavfile_sink::gr_wavfile_sink(const char *filename,
				 int n_channels,
				 unsigned int sample_rate,
				 int bits_per_sample)
  : gr_sync_block ("wavfile_sink",
		   gr_make_io_signature(1, n_channels, sizeof(float)),
		   gr_make_io_signature(0, 0, 0)),
    d_sample_rate(sample_rate), d_nchans(n_channels),
    d_fp(0), d_new_fp(0), d_updated(false)
{
  if (bits_per_sample != 8 && bits_per_sample != 16) {
    throw std::runtime_error("Invalid bits per sample (supports 8 and 16)");
  }
  d_bytes_per_sample = bits_per_sample / 8;
  d_bytes_per_sample_new = d_bytes_per_sample;
  
  if (!open(filename)) {
    throw std::runtime_error ("can't open file");
  }

  if (bits_per_sample == 8) {
    d_max_sample_val = 0xFF;
    d_min_sample_val = 0;
    d_normalize_fac  = d_max_sample_val/2;
    d_normalize_shift = 1;
  } else {
    d_max_sample_val = 0x7FFF;
    d_min_sample_val = -0x7FFF;
    d_normalize_fac  = d_max_sample_val;
    d_normalize_shift = 0;
    if (bits_per_sample != 16) {
      fprintf(stderr, "Invalid bits per sample value requested, using 16");
    }
  }
}


bool
gr_wavfile_sink::open(const char* filename)
{
  omni_mutex_lock l(d_mutex);
  
  // we use the open system call to get access to the O_LARGEFILE flag.
  int fd;
  if ((fd = ::open (filename,
		    O_WRONLY|O_CREAT|O_TRUNC|OUR_O_LARGEFILE|OUR_O_BINARY,
		    0664)) < 0){
    perror (filename);
    return false;
  }

  if (d_new_fp) {    // if we've already got a new one open, close it
    fclose(d_new_fp);
    d_new_fp = 0;
  }
  
  if ((d_new_fp = fdopen (fd, "wb")) == NULL) {
    perror (filename);
    ::close(fd);  // don't leak file descriptor if fdopen fails.
    return false;
  }
  d_updated = true;
  
  if (!gri_wavheader_write(d_new_fp,
			   d_sample_rate,
			   d_nchans,
			   d_bytes_per_sample_new)) {
    fprintf(stderr, "[%s] could not write to WAV file\n", __FILE__);
    exit(-1);
  }
  
  return true;
}


void
gr_wavfile_sink::close()
{
  omni_mutex_lock l(d_mutex);
  
  if (!d_fp)
    return;
  
  close_wav();
}

void gr_wavfile_sink::close_wav()
{
  unsigned int byte_count = d_sample_count * d_bytes_per_sample;
  
  gri_wavheader_complete(d_fp, byte_count);
  
  fclose(d_fp);
  d_fp = NULL;
}


gr_wavfile_sink::~gr_wavfile_sink ()
{
  if (d_new_fp) {
    fclose(d_new_fp);
  }

  close();
}


int
gr_wavfile_sink::work (int noutput_items,
		       gr_vector_const_void_star &input_items,
		       gr_vector_void_star &output_items)
{
  float **in = (float **) &input_items[0];
  int n_in_chans = input_items.size();
  
  short int sample_buf_s;
  
  int nwritten;
  
  do_update();	// update: d_fp is reqd
  if (!d_fp)	// drop output on the floor
    return noutput_items;
  
  for (nwritten = 0; nwritten < noutput_items; nwritten++) {
    for (int chan = 0; chan < d_nchans; chan++) {
      // Write zeros to channels which are in the WAV file
      // but don't have any inputs here
      if (chan < n_in_chans) {
	sample_buf_s = 
	  convert_to_short(in[chan][nwritten]);
      } else {
	sample_buf_s = 0;
      }
      
      gri_wav_write_sample(d_fp, sample_buf_s, d_bytes_per_sample);
      
      if (feof(d_fp) || ferror(d_fp)) {
	fprintf(stderr, "[%s] file i/o error\n", __FILE__);
	close();
	exit(-1);
      }
      d_sample_count++;
    }
  }
  
  return nwritten;
}


short int
gr_wavfile_sink::convert_to_short(float sample)
{
  sample += d_normalize_shift;
  sample *= d_normalize_fac;
  if (sample > d_max_sample_val) {
    sample = d_max_sample_val;
  } else if (sample < d_min_sample_val) {
    sample = d_min_sample_val;
  }
  
  return (short int) roundf(sample);
}


void
gr_wavfile_sink::set_bits_per_sample(int bits_per_sample)
{
  omni_mutex_lock l(d_mutex);
  if (bits_per_sample == 8 || bits_per_sample == 16) {
    d_bytes_per_sample_new = bits_per_sample / 8;
  }
}


void
gr_wavfile_sink::set_sample_rate(unsigned int sample_rate)
{
  omni_mutex_lock l(d_mutex);
  d_sample_rate = sample_rate;
}


void
gr_wavfile_sink::do_update()
{
  if (!d_updated) {
    return;
  }
  
  omni_mutex_lock     l(d_mutex);     // hold mutex for duration of this block
  if (d_fp) {
    close_wav();
  }

  d_fp = d_new_fp;                    // install new file pointer
  d_new_fp  = 0;
  d_sample_count = 0;
  d_bytes_per_sample = d_bytes_per_sample_new;

  if (d_bytes_per_sample == 1) {
    d_max_sample_val = UCHAR_MAX;
    d_min_sample_val = 0;
    d_normalize_fac  = d_max_sample_val/2;
    d_normalize_shift = 1;
  } else if (d_bytes_per_sample == 2) {
    d_max_sample_val = SHRT_MAX;
    d_min_sample_val = SHRT_MIN;
    d_normalize_fac  = d_max_sample_val;
    d_normalize_shift = 0;
  }
  
  d_updated = false;
}