ref: 462204abc7de8820a532778570b5a9549a503ec1
dir: /src/msac.h/
/* * Copyright (c) 2001-2016, Alliance for Open Media. All rights reserved * * This source code is subject to the terms of the BSD 2 Clause License and * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License * was not distributed with this source code in the LICENSE file, you can * obtain it at www.aomedia.org/license/software. If the Alliance for Open * Media Patent License 1.0 was not distributed with this source code in the * PATENTS file, you can obtain it at www.aomedia.org/license/patent. */ #ifndef __DAV1D_SRC_MSAC_H__ #define __DAV1D_SRC_MSAC_H__ #include <stdint.h> #include <stdlib.h> typedef struct MsacContext { const uint8_t *buf, *end, *bptr; int32_t tell_offs; uint32_t dif; uint16_t rng; int16_t cnt; int error; } MsacContext; void msac_init(MsacContext *c, const uint8_t *data, size_t sz); unsigned msac_decode_symbol(MsacContext *c, const uint16_t *cdf, const unsigned n_symbols); unsigned msac_decode_bool(MsacContext *c, unsigned cdf); unsigned msac_decode_bools(MsacContext *c, unsigned l); int msac_decode_subexp(MsacContext *c, int ref, unsigned n, unsigned k); int msac_decode_uniform(MsacContext *c, unsigned n); void update_cdf(uint16_t *cdf, unsigned val, unsigned nsymbs); static inline unsigned msac_decode_symbol_adapt(MsacContext *const c, uint16_t *const cdf, const unsigned n_symbols) { const unsigned val = msac_decode_symbol(c, cdf, n_symbols); update_cdf(cdf, val, n_symbols); return val; } static inline unsigned msac_decode_bool_adapt(MsacContext *const c, uint16_t *const cdf) { const unsigned bit = msac_decode_bool(c, *cdf); uint16_t bak_cdf[3] = { cdf[0], 0, cdf[1] }; update_cdf(bak_cdf, bit, 2); cdf[0] = bak_cdf[0]; cdf[1] = bak_cdf[2]; return bit; } #endif /* __DAV1D_SRC_MSAC_H__ */