mirror of
https://github.com/vgmstream/vgmstream.git
synced 2024-12-21 02:45:52 +01:00
40 lines
1.1 KiB
C
40 lines
1.1 KiB
C
|
#ifndef _LP_STREAMFILE_H_
|
||
|
|
#define _LP_STREAMFILE_H_
|
||
|
|
#include "../streamfile.h"
|
||
|
|
|
||
|
|
|
||
|
|
typedef struct {
|
||
|
|
off_t start;
|
||
|
|
} lp_io_data;
|
||
|
|
|
||
|
|
static size_t lp_io_read(STREAMFILE *sf, uint8_t *dest, off_t offset, size_t length, lp_io_data* data) {
|
||
|
|
int i;
|
||
|
|
size_t bytes = read_streamfile(dest, offset, length, sf);
|
||
|
|
|
||
|
|
/* PCM16LE frames are ROL'ed (or lower bit is ignored?) so this only works if reads are aligned
|
||
|
|
* to sizeof(uint16_t); maybe could be a new decoder but seems like a waste */
|
||
|
|
for (i = 0; i < bytes / 2 * 2; i += 2) {
|
||
|
|
if (offset + i >= data->start) {
|
||
|
|
uint16_t v = get_u16le(dest + i);
|
||
|
|
v = (v << 1) | ((v >> 15) & 0x0001);
|
||
|
|
put_u16le(dest + i, v);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return bytes;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* decrypts Enthusia "LP" PCM streams */
|
||
|
|
static STREAMFILE* setup_lp_streamfile(STREAMFILE* sf, off_t start) {
|
||
|
|
STREAMFILE* new_sf = NULL;
|
||
|
|
lp_io_data io_data = {0};
|
||
|
|
|
||
|
|
io_data.start = start;
|
||
|
|
|
||
|
|
new_sf = open_wrap_streamfile(sf);
|
||
|
|
new_sf = open_io_streamfile_f(new_sf, &io_data, sizeof(lp_io_data), lp_io_read, NULL);
|
||
|
|
return new_sf;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* _LP_STREAMFILE_H_ */
|