gzdoom/snes_spc/demo/wave_writer.c

154 lines
3.7 KiB
C
Raw Normal View History

/* snes_spc 0.9.0. http://www.slack.net/~ant/ */
#include "wave_writer.h"
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
/* Copyright (C) 2003-2007 Shay Green. This module is free software; you
can redistribute it and/or modify it under the terms of the GNU Lesser
General Public License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version. This
module 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 Lesser General Public License for more
details. You should have received a copy of the GNU Lesser General Public
License along with this module; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
enum { buf_size = 32768 * 2 };
enum { header_size = 0x2C };
typedef short sample_t;
static unsigned char* buf;
static FILE* file;
static long sample_count_;
static long sample_rate_;
static long buf_pos;
static int chan_count;
static void exit_with_error( const char* str )
{
printf( "Error: %s\n", str ); getchar();
exit( EXIT_FAILURE );
}
void wave_open( long sample_rate, const char* filename )
{
sample_count_ = 0;
sample_rate_ = sample_rate;
buf_pos = header_size;
chan_count = 1;
buf = (unsigned char*) malloc( buf_size * sizeof *buf );
if ( !buf )
exit_with_error( "Out of memory" );
file = fopen( filename, "wb" );
if ( !file )
exit_with_error( "Couldn't open WAVE file for writing" );
setvbuf( file, 0, _IOFBF, 32 * 1024L );
}
void wave_enable_stereo( void )
{
chan_count = 2;
}
static void flush_()
{
if ( buf_pos && !fwrite( buf, buf_pos, 1, file ) )
exit_with_error( "Couldn't write WAVE data" );
buf_pos = 0;
}
void wave_write( short const* in, long remain )
{
sample_count_ += remain;
while ( remain )
{
if ( buf_pos >= buf_size )
flush_();
{
unsigned char* p = &buf [buf_pos];
long n = (buf_size - buf_pos) / sizeof (sample_t);
if ( n > remain )
n = remain;
remain -= n;
/* convert to LSB first format */
while ( n-- )
{
int s = *in++;
*p++ = (unsigned char) s;
*p++ = (unsigned char) (s >> 8);
}
buf_pos = p - buf;
assert( buf_pos <= buf_size );
}
}
}
long wave_sample_count( void )
{
return sample_count_;
}
static void set_le32( void* p, unsigned long n )
{
((unsigned char*) p) [0] = (unsigned char) n;
((unsigned char*) p) [1] = (unsigned char) (n >> 8);
((unsigned char*) p) [2] = (unsigned char) (n >> 16);
((unsigned char*) p) [3] = (unsigned char) (n >> 24);
}
void wave_close( void )
{
if ( file )
{
/* generate header */
unsigned char h [header_size] =
{
'R','I','F','F',
0,0,0,0, /* length of rest of file */
'W','A','V','E',
'f','m','t',' ',
0x10,0,0,0, /* size of fmt chunk */
1,0, /* uncompressed format */
0,0, /* channel count */
0,0,0,0, /* sample rate */
0,0,0,0, /* bytes per second */
0,0, /* bytes per sample frame */
16,0, /* bits per sample */
'd','a','t','a',
0,0,0,0, /* size of sample data */
/* ... */ /* sample data */
};
long ds = sample_count_ * sizeof (sample_t);
int frame_size = chan_count * sizeof (sample_t);
set_le32( h + 0x04, header_size - 8 + ds );
h [0x16] = chan_count;
set_le32( h + 0x18, sample_rate_ );
set_le32( h + 0x1C, sample_rate_ * frame_size );
h [0x20] = frame_size;
set_le32( h + 0x28, ds );
flush_();
/* write header */
fseek( file, 0, SEEK_SET );
fwrite( h, sizeof h, 1, file );
fclose( file );
file = 0;
free( buf );
buf = 0;
}
}