int main() {
output_file = fopen("output.wav", "wb");
if (!output_file)
die_perror("failed to open file");
int samplerate = SAMPLE_RATE;
int channels = 2;
int bitspersample = 16;
int datarate = samplerate * channels * (bitspersample / 8);
int blockalign = channels * (bitspersample / 8);
// write wav header
output_write("RIFF", 4);
long riff_len_pos = ftell(output_file); // need to write 36+datalen to riff_len_pos
write_le32(0);
output_write("WAVE", 4);
output_write("fmt ", 4);
write_le32(16);
write_le16(1);
write_le16(channels);
write_le32(samplerate);
write_le32(datarate);
write_le16(blockalign);
write_le16(bitspersample);
output_write("data", 4);
long wav_data_pos = ftell(output_file); // need to write datalen to wav_data_pos
write_le32(0);
int i;
for (i = 0; i < 22050; i++) output_sample(0, 0); // write 500ms of silence
write_pulse(1, 4909, 1000000); // command start
write_pulse(0, 4320, 1000000);
i = 0;
unsigned code = 0xe0e040bf;
for (i = 0; i < 32; i++) {
int bit = (code >> (31 - i)) & 0x1;
if (bit) {
write_pulse(1, 818, 1000000); // 1 bit
write_pulse(0, 1425, 1000000);
} else {
write_pulse(1, 818, 1000000); // 0 bit
write_pulse(0, 325, 1000000);
}
}
write_pulse(1, 717, 1000000); // command stop
write_pulse(0, 717, 1000000);
for (i = 0; i < 22050; i++) output_sample(0, 0); // write 500ms of silence
fseek(output_file, riff_len_pos, SEEK_SET);
write_le32(36 + datalen);
fseek(output_file, wav_data_pos, SEEK_SET);
write_le32(datalen);
fclose(output_file);
return 0;
}
/* Convert RLE block to a TZX DRB as TZX CSW block support is limited :/ */
static libspectrum_error
tzx_write_rle( libspectrum_tape_block *block, libspectrum_byte **buffer,
libspectrum_byte **ptr, size_t *length,
libspectrum_tape *tape,
libspectrum_tape_iterator iterator )
{
libspectrum_error error;
libspectrum_tape_block_state it;
libspectrum_dword scale = libspectrum_tape_block_scale( block );
libspectrum_dword pulse_tstates = 0;
libspectrum_dword balance_tstates = 0;
int flags = 0;
libspectrum_tape_block *raw_block =
libspectrum_tape_block_alloc( LIBSPECTRUM_TAPE_BLOCK_RAW_DATA );
libspectrum_tape_block_set_bit_length( raw_block, scale );
libspectrum_tape_block_set_pause ( raw_block, 0 );
rle_state.bits_used = 0;
rle_state.level = 0;
rle_state.length = 0;
rle_state.tape_length = 8192;
rle_state.tape_buffer = libspectrum_malloc( rle_state.tape_length );
*rle_state.tape_buffer = 0;
it.current_block = iterator;
error = libspectrum_tape_block_init( block, &it );
if( error != LIBSPECTRUM_ERROR_NONE ) {
libspectrum_free( rle_state.tape_buffer );
libspectrum_tape_block_free( raw_block );
return error;
}
while( !(flags & LIBSPECTRUM_TAPE_FLAGS_BLOCK) ) {
libspectrum_dword pulse_length = 0;
/* Use internal version of this that doesn't bugger up the
external tape status */
error = libspectrum_tape_get_next_edge_internal( &pulse_tstates, &flags,
tape, &it );
if( error != LIBSPECTRUM_ERROR_NONE ) {
libspectrum_free( rle_state.tape_buffer );
libspectrum_tape_block_free( raw_block );
return error;
}
balance_tstates += pulse_tstates;
/* next set of pulses is: balance_tstates / scale; */
pulse_length = balance_tstates / scale;
balance_tstates = balance_tstates % scale;
/* write pulse_length bits of the current level into the buffer */
write_pulse( pulse_length );
}
if( rle_state.length || rle_state.bits_used ) {
if( rle_state.bits_used ) {
rle_state.length++;
} else {
rle_state.bits_used = 8;
}
error = libspectrum_tape_block_set_bits_in_last_byte( raw_block,
rle_state.bits_used );
if( error != LIBSPECTRUM_ERROR_NONE ) {
libspectrum_free( rle_state.tape_buffer );
libspectrum_tape_block_free( raw_block );
return error;
}
error = libspectrum_tape_block_set_data_length( raw_block,
rle_state.length );
if( error != LIBSPECTRUM_ERROR_NONE ) {
libspectrum_free( rle_state.tape_buffer );
libspectrum_tape_block_free( raw_block );
return error;
}
error = libspectrum_tape_block_set_data( raw_block, rle_state.tape_buffer );
if( error != LIBSPECTRUM_ERROR_NONE ) {
libspectrum_free( rle_state.tape_buffer );
libspectrum_tape_block_free( raw_block );
return error;
}
/* now have tzx_write_raw_data finish the job */
tzx_write_raw_data( raw_block, buffer, ptr, length );
} else {
libspectrum_free( rle_state.tape_buffer );
}
return libspectrum_tape_block_free( raw_block );
}
