diff options
Diffstat (limited to 'vgmsplit.c')
| -rw-r--r-- | vgmsplit.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/vgmsplit.c b/vgmsplit.c new file mode 100644 index 0000000..7a4213b --- /dev/null +++ b/vgmsplit.c @@ -0,0 +1,218 @@ +/* + 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; +} |