61 lines
1.7 KiB
C
61 lines
1.7 KiB
C
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/*
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* ELS (Entropy Logarithmic-Scale) decoder
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*
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* Copyright (c) 2013 Maxim Poliakovski
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* Entropy Logarithmic-Scale binary arithmetic coder
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*/
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#ifndef AVCODEC_ELSDEC_H
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#define AVCODEC_ELSDEC_H
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#include <stdint.h>
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#include <sys/types.h>
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#define ELS_EXPGOLOMB_LEN 10
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typedef struct ElsDecCtx {
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const uint8_t *in_buf;
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unsigned x;
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size_t data_size;
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int j, t, diff, err;
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} ElsDecCtx;
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typedef struct ElsRungNode {
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uint8_t rung;
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uint16_t next_index;
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} ElsRungNode;
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typedef struct ElsUnsignedRung {
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uint8_t prefix_rung[ELS_EXPGOLOMB_LEN + 1];
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ElsRungNode *rem_rung_list;
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size_t rung_list_size;
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uint16_t avail_index;
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} ElsUnsignedRung;
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void ff_els_decoder_init(ElsDecCtx *ctx, const uint8_t *in, size_t data_size);
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void ff_els_decoder_uninit(ElsUnsignedRung *rung);
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int ff_els_decode_bit(ElsDecCtx *ctx, unsigned char *rung);
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unsigned ff_els_decode_unsigned(ElsDecCtx *ctx, ElsUnsignedRung *ur);
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#endif /* AVCODEC_ELSDEC_H */
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