2 * Shared functions between AMR codecs
4 * Copyright (c) 2010 Marcelo Galvao Povoa
6 * This file is part of Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * Libav is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #ifdef AMR_USE_16BIT_TABLES
29 #define R_TABLE_TYPE uint16_t
31 #define R_TABLE_TYPE uint8_t
35 * Fill the frame structure variables from bitstream by parsing the
36 * given reordering table that uses the following format:
38 * Each field (16 bits) in the AMR Frame is stored as:
39 * - one byte for the number of bits in the field
40 * - one byte for the field index
41 * - then, one byte for each bit of the field (from most-significant to least)
42 * of the position of that bit in the AMR frame.
44 * @param out pointer to the frame struct
45 * @param size the size in bytes of the frame struct
46 * @param data input bitstream after the frame header
47 * @param ord_table the reordering table as above
49 static inline void ff_amr_bit_reorder(uint16_t *out, int size,
51 const R_TABLE_TYPE *ord_table)
56 while ((field_size = *ord_table++)) {
58 int field_offset = *ord_table++;
59 while (field_size--) {
60 int bit = *ord_table++;
62 field |= data[bit >> 3] >> (bit & 7) & 1;
64 out[field_offset] = field;
68 #endif /* AVCODEC_AMR_H */