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// license:BSD-3-Clause
// copyright-holders:Aaron Giles
#include "wavwrite.h"
#include "osdcomm.h"
#include <cstdio>
#include <new>
#include <string>
#include <vector>
namespace util {
struct wav_file
{
FILE *file = nullptr;
std::vector<std::int16_t> temp;
std::uint32_t total_offs = 0U;
std::uint32_t data_offs = 0U;
};
wav_file_ptr wav_open(std::string_view filename, int sample_rate, int channels)
{
std::uint32_t temp32;
std::uint16_t temp16;
// allocate memory for the wav struct
wav_file_ptr wav(new (std::nothrow) wav_file);
if (!wav)
return nullptr;
// create the file
wav->file = std::fopen(std::string(filename).c_str(), "wb"); // ugly - need to force NUL termination on filename
if (!wav->file)
return nullptr;
// write the 'RIFF' header
std::fwrite("RIFF", 1, 4, wav->file);
// write the total size
temp32 = 0;
wav->total_offs = std::ftell(wav->file);
std::fwrite(&temp32, 1, 4, wav->file);
// write the 'WAVE' type
std::fwrite("WAVE", 1, 4, wav->file);
// write the 'fmt ' tag
std::fwrite("fmt ", 1, 4, wav->file);
// write the format length
temp32 = little_endianize_int32(16);
std::fwrite(&temp32, 1, 4, wav->file);
// write the format (PCM)
temp16 = little_endianize_int16(1);
std::fwrite(&temp16, 1, 2, wav->file);
// write the channels
temp16 = little_endianize_int16(channels);
std::fwrite(&temp16, 1, 2, wav->file);
// write the sample rate
temp32 = little_endianize_int32(sample_rate);
std::fwrite(&temp32, 1, 4, wav->file);
// write the bytes/second
std::uint32_t const bps = sample_rate * 2 * channels;
temp32 = little_endianize_int32(bps);
std::fwrite(&temp32, 1, 4, wav->file);
// write the block align
std::uint16_t const align = 2 * channels;
temp16 = little_endianize_int16(align);
std::fwrite(&temp16, 1, 2, wav->file);
// write the bits/sample
temp16 = little_endianize_int16(16);
std::fwrite(&temp16, 1, 2, wav->file);
// write the 'data' tag
std::fwrite("data", 1, 4, wav->file);
// write the data length
temp32 = 0;
wav->data_offs = std::ftell(wav->file);
std::fwrite(&temp32, 1, 4, wav->file);
return wav;
}
void wav_close(wav_file *wav)
{
if (!wav)
return;
if (wav->file)
{
std::uint32_t temp32;
std::uint32_t const total = std::ftell(wav->file);
// update the total file size
std::fseek(wav->file, wav->total_offs, SEEK_SET);
temp32 = total - (wav->total_offs + 4);
temp32 = little_endianize_int32(temp32);
std::fwrite(&temp32, 1, 4, wav->file);
// update the data size
std::fseek(wav->file, wav->data_offs, SEEK_SET);
temp32 = total - (wav->data_offs + 4);
temp32 = little_endianize_int32(temp32);
std::fwrite(&temp32, 1, 4, wav->file);
std::fclose(wav->file);
}
delete wav;
}
void wav_add_data_16(wav_file &wav, int16_t *data, int samples)
{
// just write and flush the data
std::fwrite(data, 2, samples, wav.file);
std::fflush(wav.file);
}
void wav_add_data_32(wav_file &wav, int32_t *data, int samples, int shift)
{
if (!samples)
return;
// resize dynamic array - don't want it to copy if it needs to expand
wav.temp.clear();
wav.temp.resize(samples);
// clamp
for (int i = 0; i < samples; i++)
{
int val = data[i] >> shift;
wav.temp[i] = (val < -32768) ? -32768 : (val > 32767) ? 32767 : val;
}
// write and flush
std::fwrite(&wav.temp[0], 2, samples, wav.file);
std::fflush(wav.file);
}
void wav_add_data_16lr(wav_file &wav, int16_t *left, int16_t *right, int samples)
{
if (!samples)
return;
// resize dynamic array - don't want it to copy if it needs to expand
wav.temp.clear();
wav.temp.resize(samples * 2);
// interleave
for (int i = 0; i < samples * 2; i++)
wav.temp[i] = (i & 1) ? right[i / 2] : left[i / 2];
// write and flush
std::fwrite(&wav.temp[0], 4, samples, wav.file);
std::fflush(wav.file);
}
void wav_add_data_32lr(wav_file &wav, int32_t *left, int32_t *right, int samples, int shift)
{
if (!samples)
return;
// resize dynamic array - don't want it to copy if it needs to expand
wav.temp.clear();
wav.temp.resize(samples * 2);
// interleave
for (int i = 0; i < samples * 2; i++)
{
int val = (i & 1) ? right[i / 2] : left[i / 2];
val >>= shift;
wav.temp[i] = (val < -32768) ? -32768 : (val > 32767) ? 32767 : val;
}
// write and flush
std::fwrite(&wav.temp[0], 4, samples, wav.file);
std::fflush(wav.file);
}
} // namespace util
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