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/*
Copyright 2015 Michael Pavone
This file is part of BlastEm.
BlastEm is free software distributed under the terms of the GNU General Public License version 3 or greater. See COPYING for full license text.
*/
#include "ym2612.h"
#include "vgm.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define OUT_CHANNELS 10
#define DAC_CHANNEL 5
#define PSG_BASE 6
#define SAMPLE_THRESHOLD 100
int main(int argc, char ** argv)
{
data_block *blocks = NULL;
data_block *seek_block = NULL;
uint32_t seek_offset;
uint32_t block_offset;
FILE * f = fopen(argv[1], "rb");
vgm_header header;
size_t bytes = fread(&header, 1, sizeof(header), f);
if (bytes != sizeof(header)) {
fputs("Error reading file\n", stderr);
exit(1);
}
if (header.version < 0x150 || !header.data_offset) {
header.data_offset = 0xC;
}
fseek(f, header.data_offset + 0x34, SEEK_SET);
uint32_t data_size = header.eof_offset + 4 - (header.data_offset + 0x34);
uint8_t * data = malloc(data_size);
data_size = fread(data, 1, data_size, f);
fclose(f);
uint8_t *buffers[OUT_CHANNELS];
uint8_t *out_pos[OUT_CHANNELS];
uint8_t has_real_data[OUT_CHANNELS];
buffers[0] = malloc(data_size * OUT_CHANNELS);
out_pos[0] = buffers[0];
has_real_data[0] = 0;
for (int i = 1; i < OUT_CHANNELS; i++)
{
buffers[i] = buffers[i-1] + data_size;
out_pos[i] = buffers[i];
has_real_data[i] = 0;
}
uint8_t * end = data + data_size;
uint8_t * cur = data;
uint32_t current_cycle = 0;
uint8_t psg_latch = 0;
uint8_t param,reg;
uint8_t channel;
uint32_t sample_count = 0;
uint8_t last_cmd;
while (cur < end) {
uint8_t cmd = *(cur++);
switch(cmd)
{
case CMD_PSG_STEREO:
//ignore for now
cur++;
break;
case CMD_PSG:
param = *(cur++);
if (param & 0x80) {
psg_latch = param;
channel = param >> 5 & 3;
} else {
channel = psg_latch >> 5 & 3;
}
*(out_pos[PSG_BASE+channel]++) = cmd;
*(out_pos[PSG_BASE+channel]++) = param;
has_real_data[PSG_BASE+channel] = 1;
break;
case CMD_YM2612_0:
reg = *(cur++);
param = *(cur++);
if (reg < REG_KEY_ONOFF) {
for (int i = 0; i < 6; i++)
{
*(out_pos[i]++) = cmd;
*(out_pos[i]++) = reg;
*(out_pos[i]++) = param;
}
break;
} else if(reg == REG_DAC || reg == REG_DAC_ENABLE) {
if (reg == REG_DAC) {
sample_count++;
}
channel = DAC_CHANNEL;
} else if(reg == REG_KEY_ONOFF) {
channel = param & 7;
if (channel > 2) {
channel--;
}
if (param & 0xF0) {
has_real_data[channel] = 1;
}
} else if (reg >= REG_FNUM_LOW_CH3 && reg < REG_ALG_FEEDBACK) {
channel = 2;
} else {
channel = 255;
}
case CMD_YM2612_1:
if (cmd == CMD_YM2612_1) {
reg = *(cur++);
param = *(cur++);
channel = 255;
}
if (channel >= PSG_BASE) {
if (reg >= REG_DETUNE_MULT && reg < REG_FNUM_LOW) {
channel = (cmd == CMD_YM2612_0 ? 0 : 3) + (reg & 0xC >> 2);
} else if ((reg >= REG_FNUM_LOW && reg < REG_FNUM_LOW_CH3) || (reg >= REG_ALG_FEEDBACK && reg < 0xC0)) {
channel = (cmd == CMD_YM2612_0 ? 0 : 3) + (reg & 0x3);
} else {
fprintf(stderr, "WARNING: Skipping nrecognized write to register %X on part %d\n", reg, (cmd == CMD_YM2612_0 ? 1 : 2));
}
}
if (channel < PSG_BASE) {
*(out_pos[channel]++) = cmd;
*(out_pos[channel]++) = reg;
*(out_pos[channel]++) = param;
}
break;
case CMD_WAIT: {
reg = *(cur++);
param = *(cur++);
for (int i = 0; i < OUT_CHANNELS; i++)
{
*(out_pos[i]++) = cmd;
*(out_pos[i]++) = reg;
*(out_pos[i]++) = param;
}
break;
}
case CMD_WAIT_60:
case CMD_WAIT_50:
case CMD_END:
for (int i = 0; i < OUT_CHANNELS; i++)
{
*(out_pos[i]++) = cmd;
}
cur = end;
break;
case CMD_DATA: {
uint8_t * start = cur - 1;
cur++; //skip compat command
uint8_t data_type = *(cur++);
uint32_t data_size = *(cur++);
data_size |= *(cur++) << 8;
data_size |= *(cur++) << 16;
data_size |= *(cur++) << 24;
if (cur + data_size > end) {
data_size = end - cur;
}
cur += data_size;
if (data_type == DATA_YM2612_PCM) {
memcpy(out_pos[DAC_CHANNEL], start, cur-start);
out_pos[DAC_CHANNEL] += cur-start;
} else {
fprintf(stderr, "WARNING: Skipping data block with unrecognized type %X\n", data_type);
}
break;
}
case CMD_DATA_SEEK: {
memcpy(out_pos[DAC_CHANNEL], cur-1, 5);
out_pos[DAC_CHANNEL] += 5;
cur += 4;
break;
}
default:
if (cmd >= CMD_WAIT_SHORT && cmd < (CMD_WAIT_SHORT + 0x10)) {
for (int i = 0; i < OUT_CHANNELS; i++)
{
*(out_pos[i]++) = cmd;
}
} else if (cmd >= CMD_YM2612_DAC && cmd < CMD_DAC_STREAM_SETUP) {
*(out_pos[DAC_CHANNEL]++) = cmd;
sample_count++;
} else {
fprintf(stderr, "unimplemented command: %X at offset %X, last valid command was %X\n", cmd, (unsigned int)(cur - data - 1), last_cmd);
exit(1);
}
}
last_cmd = cmd;
}
if (sample_count > SAMPLE_THRESHOLD) {
has_real_data[DAC_CHANNEL] = 1;
}
for (int i = 0; i < OUT_CHANNELS; i++)
{
if (has_real_data[i]) {
char fname[11];
sprintf(fname, i < PSG_BASE ? "ym_%d.vgm" : "psg_%d.vgm", i < PSG_BASE ? i : i - PSG_BASE);
f = fopen(fname, "wb");
if (!f) {
fprintf(stderr, "Failed to open %s for writing\n", fname);
exit(1);
}
data_size = out_pos[i] - buffers[i];
header.eof_offset = (header.data_offset + 0x34) + data_size - 4;
fwrite(&header, 1, sizeof(header), f);
fseek(f, header.data_offset + 0x34, SEEK_SET);
fwrite(buffers[i], 1, data_size, f);
fclose(f);
}
}
return 0;
}
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