43 lines
1.1 KiB
C
43 lines
1.1 KiB
C
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/*
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* jdarith.c
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*
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* Copyright (C) 1991, Thomas G. Lane.
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* This file is part of the Independent JPEG Group's software.
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* For conditions of distribution and use, see the accompanying README file.
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*
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* This file contains arithmetic entropy decoding routines.
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* These routines are invoked via the methods entropy_decode
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* and entropy_decoder_init/term.
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*/
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#include "jinclude.h"
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#ifdef ARITH_CODING_SUPPORTED
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/*
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* The arithmetic coding option of the JPEG standard specifies Q-coding,
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* which is covered by patents held by IBM (and possibly AT&T and Mitsubishi).
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* At this time it does not appear to be legal for the Independent JPEG
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* Group to distribute software that implements arithmetic coding.
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* We have therefore removed arithmetic coding support from the
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* distributed source code.
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*
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* We're not happy about it either.
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*/
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/*
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* The method selection routine for arithmetic entropy decoding.
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*/
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GLOBAL void
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jseldarithmetic (decompress_info_ptr cinfo)
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{
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if (cinfo->arith_code) {
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ERREXIT(cinfo->emethods, "Sorry, there are legal restrictions on arithmetic coding");
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}
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}
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#endif /* ARITH_CODING_SUPPORTED */
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