vgmstream/src/meta/vgs.c
2023-01-20 17:30:17 +01:00

73 lines
2.1 KiB
C

#include "meta.h"
#include "../util.h"
#include "../coding/coding.h"
#include "../layout/layout.h"
/* VGS - from Guitar Hero Encore - Rocks the 80s, Guitar Hero II PS2 */
VGMSTREAM* init_vgmstream_vgs(STREAMFILE *sf) {
VGMSTREAM* vgmstream = NULL;
off_t start_offset;
size_t channel_size = 0, stream_data_size, stream_frame_count;
int channels = 0, loop_flag = 0, sample_rate = 0, stream_sample_rate;
int i;
/* checks */
if (!is_id32be(0x00,sf, "VgS!"))
goto fail;
/* 0x04: version? */
if (!check_extensions(sf,"vgs"))
goto fail;
/* contains N streams, which can have one less frame, or half frame and sample rate */
for (i = 0; i < 8; i++) {
stream_sample_rate = read_32bitLE(0x08 + 0x08*i + 0x00,sf);
stream_frame_count = read_32bitLE(0x08 + 0x08*i + 0x04,sf);
stream_data_size = stream_frame_count*0x10;
if (stream_sample_rate == 0)
break;
if (!sample_rate || !channel_size) {
sample_rate = stream_sample_rate;
channel_size = stream_data_size;
}
/* some streams end 1 frame early */
if (channel_size - 0x10 == stream_data_size) {
channel_size -= 0x10;
}
/* Guitar Hero II sometimes uses half sample rate for last stream */
if (sample_rate != stream_sample_rate) {
VGM_LOG("VGS: ignoring stream %i\n", i);
//total_streams++; // todo handle substreams
break;
}
channels++;
}
start_offset = 0x80;
/* build the VGMSTREAM */
vgmstream = allocate_vgmstream(channels, loop_flag);
if (!vgmstream) goto fail;
vgmstream->meta_type = meta_VGS;
vgmstream->sample_rate = sample_rate;
vgmstream->num_samples = ps_bytes_to_samples(channel_size * channels, channels);
vgmstream->coding_type = coding_PSX_badflags; /* flag = stream/channel number */
vgmstream->layout_type = layout_blocked_vgs;
if (!vgmstream_open_stream(vgmstream, sf, start_offset))
goto fail;
return vgmstream;
fail:
close_vgmstream(vgmstream);
return NULL;
}