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3383a53e7d
The existing functions defined in intfloat_readwrite.[ch] are both slow and incorrect (infinities are not handled). This introduces a new header with fast, inline conversion functions using direct union punning assuming an IEEE-754 system, an assumption already made throughout the code. The one use of Intel/Motorola extended 80-bit format is replaced by simpler code sufficient under the present constraints (positive normal values). The old functions are marked deprecated and retained for compatibility. Signed-off-by: Mans Rullgard <mans@mansr.com>
74 lines
1.7 KiB
C
74 lines
1.7 KiB
C
/*
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* Copyright (c) 2011 Mans Rullgard
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*
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* This file is part of Libav.
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*
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* Libav 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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* Libav 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 Libav; 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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#ifndef AVUTIL_INTFLOAT_H
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#define AVUTIL_INTFLOAT_H
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#include <stdint.h>
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#include "attributes.h"
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union av_intfloat32 {
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uint32_t i;
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float f;
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};
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union av_intfloat64 {
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uint64_t i;
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double f;
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};
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/**
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* Reinterpret a 32-bit integer as a float.
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*/
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static av_always_inline float av_int2float(uint32_t i)
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{
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union av_intfloat32 v = { .i = i };
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return v.f;
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}
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/**
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* Reinterpret a float as a 32-bit integer.
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*/
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static av_always_inline uint32_t av_float2int(float f)
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{
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union av_intfloat32 v = { .f = f };
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return v.i;
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}
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/**
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* Reinterpret a 64-bit integer as a double.
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*/
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static av_always_inline double av_int2double(uint64_t i)
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{
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union av_intfloat64 v = { .i = i };
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return v.f;
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}
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/**
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* Reinterpret a double as a 64-bit integer.
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*/
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static av_always_inline uint64_t av_double2int(double f)
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{
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union av_intfloat64 v = { .f = f };
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return v.i;
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}
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#endif /* AVUTIL_INTFLOAT_H */
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