5 * This work is licensed under the terms of MAME license.
6 * See COPYING file in the top-level directory.
10 int mp3_find_sync_word(const unsigned char *buf, int size)
12 const unsigned char *p, *pe;
14 /* find byte-aligned syncword - need 12 (MPEG 1,2) or 11 (MPEG 2.5) matching bits */
15 for (p = buf, pe = buf + size - 3; p <= pe; p++)
21 if ((pn & 0xf8) != 0xf8 || // currently must be MPEG1
22 (pn & 6) == 0) { // invalid layer
26 if ((pn & 0xf0) < 0x20 || (pn & 0xf0) == 0xf0 || // bitrates
27 (pn & 0x0c) != 0) { // not 44kHz