83 lines
3.0 KiB
C
83 lines
3.0 KiB
C
/*
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* SpanDSP - a series of DSP components for telephony
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*
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* t81_t82_arith_coding.h - ITU T.81 and T.82 QM-coder arithmetic encoding
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* and decoding
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*
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* Written by Steve Underwood <steveu@coppice.org>
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*
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* Copyright (C) 2009 Steve Underwood
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*
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* All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License version 2.1,
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* as published by the Free Software Foundation.
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*
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* This program 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
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* GNU 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 this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/*! \file */
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#if !defined(_SPANDSP_T81_T82_ARITH_CODING_H_)
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#define _SPANDSP_T81_T82_ARITH_CODING_H_
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/*! \page t81_t82_arith_coding_page T.81 and T.82 QM-coder arithmetic encoding and decoding
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\section t81_t82_arith_coding_page_sec_1 What does it do?
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A similar arithmetic coder, called the QM-coder, is used by several image compression
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schemes. These routines implement this coder in a (hopefully) reusable way.
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\section t81_t82_arith_coding_page_sec_1 How does it work?
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*/
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/* State of a working instance of the arithmetic encoder */
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typedef struct t81_t82_arith_encode_state_s t81_t82_arith_encode_state_t;
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/* State of a working instance of the arithmetic decoder */
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typedef struct t81_t82_arith_decode_state_s t81_t82_arith_decode_state_t;
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#if defined(__cplusplus)
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extern "C"
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{
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#endif
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SPAN_DECLARE(t81_t82_arith_encode_state_t *) t81_t82_arith_encode_init(t81_t82_arith_encode_state_t *s,
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void (*output_byte_handler)(void *, int),
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void *user_data);
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SPAN_DECLARE(int) t81_t82_arith_encode_restart(t81_t82_arith_encode_state_t *s, int reuse_st);
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SPAN_DECLARE(int) t81_t82_arith_encode_release(t81_t82_arith_encode_state_t *s);
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SPAN_DECLARE(int) t81_t82_arith_encode_free(t81_t82_arith_encode_state_t *s);
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SPAN_DECLARE(void) t81_t82_arith_encode(t81_t82_arith_encode_state_t *s, int cx, int pix);
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SPAN_DECLARE(void) t81_t82_arith_encode_flush(t81_t82_arith_encode_state_t *s);
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SPAN_DECLARE(t81_t82_arith_decode_state_t *) t81_t82_arith_decode_init(t81_t82_arith_decode_state_t *s);
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SPAN_DECLARE(int) t81_t82_arith_decode_restart(t81_t82_arith_decode_state_t *s, int reuse_st);
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SPAN_DECLARE(int) t81_t82_arith_decode_release(t81_t82_arith_decode_state_t *s);
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SPAN_DECLARE(int) t81_t82_arith_decode_free(t81_t82_arith_decode_state_t *s);
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SPAN_DECLARE(int) t81_t82_arith_decode(t81_t82_arith_decode_state_t *s, int cx);
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#if defined(__cplusplus)
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}
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#endif
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#endif
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/*- End of file ------------------------------------------------------------*/
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