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- /*
- * Shared functions between AMR codecs
- *
- * Copyright (c) 2010 Marcelo Galvao Povoa
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
- #ifndef AVCODEC_AMR_H
- #define AVCODEC_AMR_H
- #include <string.h>
- #include "avcodec.h"
- #ifdef AMR_USE_16BIT_TABLES
- typedef uint16_t R_TABLE_TYPE;
- #else
- typedef uint8_t R_TABLE_TYPE;
- #endif
- /**
- * Fill the frame structure variables from bitstream by parsing the
- * given reordering table that uses the following format:
- *
- * Each field (16 bits) in the AMR Frame is stored as:
- * - one byte for the number of bits in the field
- * - one byte for the field index
- * - then, one byte for each bit of the field (from most-significant to least)
- * of the position of that bit in the AMR frame.
- *
- * @param out pointer to the frame struct
- * @param size the size in bytes of the frame struct
- * @param data input bitstream after the frame header
- * @param ord_table the reordering table as above
- */
- static inline void ff_amr_bit_reorder(uint16_t *out, int size,
- const uint8_t *data,
- const R_TABLE_TYPE *ord_table)
- {
- int field_size;
- memset(out, 0, size);
- while ((field_size = *ord_table++)) {
- int field = 0;
- int field_offset = *ord_table++;
- while (field_size--) {
- int bit = *ord_table++;
- field <<= 1;
- field |= data[bit >> 3] >> (bit & 7) & 1;
- }
- out[field_offset >> 1] = field;
- }
- }
- #endif /* AVCODEC_AMR_H */
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