mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-28 20:53:54 +02:00
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
/*
|
|
* Copyright (c) 2011 Mans Rullgard
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* Libav is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#ifndef AVUTIL_INTFLOAT_H
|
|
#define AVUTIL_INTFLOAT_H
|
|
|
|
#include <stdint.h>
|
|
#include "attributes.h"
|
|
|
|
union av_intfloat32 {
|
|
uint32_t i;
|
|
float f;
|
|
};
|
|
|
|
union av_intfloat64 {
|
|
uint64_t i;
|
|
double f;
|
|
};
|
|
|
|
/**
|
|
* Reinterpret a 32-bit integer as a float.
|
|
*/
|
|
static av_always_inline float av_int2float(uint32_t i)
|
|
{
|
|
union av_intfloat32 v = { .i = i };
|
|
return v.f;
|
|
}
|
|
|
|
/**
|
|
* Reinterpret a float as a 32-bit integer.
|
|
*/
|
|
static av_always_inline uint32_t av_float2int(float f)
|
|
{
|
|
union av_intfloat32 v = { .f = f };
|
|
return v.i;
|
|
}
|
|
|
|
/**
|
|
* Reinterpret a 64-bit integer as a double.
|
|
*/
|
|
static av_always_inline double av_int2double(uint64_t i)
|
|
{
|
|
union av_intfloat64 v = { .i = i };
|
|
return v.f;
|
|
}
|
|
|
|
/**
|
|
* Reinterpret a double as a 64-bit integer.
|
|
*/
|
|
static av_always_inline uint64_t av_double2int(double f)
|
|
{
|
|
union av_intfloat64 v = { .f = f };
|
|
return v.i;
|
|
}
|
|
|
|
#endif /* AVUTIL_INTFLOAT_H */
|