blob: 627f83229ed2eb7be35d7238e06a295e20a2cd8e [file] [log] [blame]
* Copyright (c) 2012 Andrew D'Addesio
* Copyright (c) 2013-2014 Mozilla Corporation
* Copyright (c) 2017 Rostislav Pehlivanov <>
* 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
* 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
#include <stdint.h>
#include "get_bits.h"
#define opus_ilog(i) (av_log2(i) + !!(i))
typedef struct RawBitsContext {
const uint8_t *position;
uint32_t bytes;
uint32_t cachelen;
uint32_t cacheval;
} RawBitsContext;
typedef struct OpusRangeCoder {
GetBitContext gb;
RawBitsContext rb;
uint32_t range;
uint32_t value;
uint32_t total_bits;
/* Encoder */
uint8_t buf[OPUS_MAX_PACKET_SIZE + 12]; /* memcpy vs (memmove + overreading) */
uint8_t *rng_cur; /* Current range coded byte */
int ext; /* Awaiting propagation */
int rem; /* Carryout flag */
/* Encoding stats */
int waste;
} OpusRangeCoder;
* CELT: estimate bits of entropy that have thus far been consumed for the
* current CELT frame, to integer and fractional (1/8th bit) precision
static av_always_inline uint32_t opus_rc_tell(const OpusRangeCoder *rc)
return rc->total_bits - av_log2(rc->range) - 1;
static av_always_inline uint32_t opus_rc_tell_frac(const OpusRangeCoder *rc)
uint32_t i, total_bits, rcbuffer, range;
total_bits = rc->total_bits << 3;
rcbuffer = av_log2(rc->range) + 1;
range = rc->range >> (rcbuffer-16);
for (i = 0; i < 3; i++) {
int bit;
range = range * range >> 15;
bit = range >> 16;
rcbuffer = rcbuffer << 1 | bit;
range >>= bit;
return total_bits - rcbuffer;
uint32_t ff_opus_rc_dec_cdf(OpusRangeCoder *rc, const uint16_t *cdf);
void ff_opus_rc_enc_cdf(OpusRangeCoder *rc, int val, const uint16_t *cdf);
uint32_t ff_opus_rc_dec_log(OpusRangeCoder *rc, uint32_t bits);
void ff_opus_rc_enc_log(OpusRangeCoder *rc, int val, uint32_t bits);
uint32_t ff_opus_rc_dec_uint_step(OpusRangeCoder *rc, int k0);
void ff_opus_rc_enc_uint_step(OpusRangeCoder *rc, uint32_t val, int k0);
uint32_t ff_opus_rc_dec_uint_tri(OpusRangeCoder *rc, int qn);
void ff_opus_rc_enc_uint_tri(OpusRangeCoder *rc, uint32_t k, int qn);
uint32_t ff_opus_rc_dec_uint(OpusRangeCoder *rc, uint32_t size);
void ff_opus_rc_enc_uint(OpusRangeCoder *rc, uint32_t val, uint32_t size);
uint32_t ff_opus_rc_get_raw(OpusRangeCoder *rc, uint32_t count);
void ff_opus_rc_put_raw(OpusRangeCoder *rc, uint32_t val, uint32_t count);
int ff_opus_rc_dec_laplace(OpusRangeCoder *rc, uint32_t symbol, int decay);
void ff_opus_rc_enc_laplace(OpusRangeCoder *rc, int *value, uint32_t symbol, int decay);
int ff_opus_rc_dec_init(OpusRangeCoder *rc, const uint8_t *data, int size);
void ff_opus_rc_dec_raw_init(OpusRangeCoder *rc, const uint8_t *rightend, uint32_t bytes);
void ff_opus_rc_enc_end(OpusRangeCoder *rc, uint8_t *dst, int size);
void ff_opus_rc_enc_init(OpusRangeCoder *rc);
rc_rollback_bits = opus_rc_tell_frac(rc); \
rc_rollback_ctx = *rc
uint32_t rc_rollback_bits = opus_rc_tell_frac(rc); \
OpusRangeCoder rc_rollback_ctx = *rc \
(opus_rc_tell_frac(rc) - rc_rollback_bits)
memcpy(rc, &rc_rollback_ctx, sizeof(OpusRangeCoder)); \
#endif /* AVCODEC_OPUS_RC_H */