mirror of
https://github.com/xenia-project/FFmpeg.git
synced 2024-11-24 12:09:55 +00:00
71 lines
2.2 KiB
C
71 lines
2.2 KiB
C
/*
|
|
* Shared functions between AMR codecs
|
|
*
|
|
* Copyright (c) 2010 Marcelo Galvao Povoa
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; 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
|
|
#define R_TABLE_TYPE uint16_t
|
|
#else
|
|
#define R_TABLE_TYPE uint8_t
|
|
#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 */
|