ImfFramesPerSecond.h

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//
// SPDX-License-Identifier: BSD-3-Clause
// Copyright (c) Contributors to the OpenEXR Project.
//

#ifndef INCLUDED_IMF_FRAMES_PER_SECOND_H
#define INCLUDED_IMF_FRAMES_PER_SECOND_H

//-----------------------------------------------------------------------------
//
//      Convenience functions related to the framesPerSecond attribute
//
//      Functions that return the exact values for commonly used frame rates:
//
//          name                frames per second
//
//          fps_23_976()        23.976023...
//          fps_24()            24.0            35mm film frames
//          fps_25()            25.0            PAL video frames
//          fps_29_97()         29.970029...    NTSC video frames
//          fps_30()            30.0            60Hz HDTV frames
//          fps_47_952()        47.952047...
//          fps_48()            48.0
//          fps_50()            50.0            PAL video fields
//          fps_59_94()         59.940059...    NTSC video fields
//          fps_60()            60.0            60Hz HDTV fields
//
//      Functions that try to convert inexact frame rates into exact ones:
//
//          Given a frame rate, fps, that is close to one of the pre-defined
//          frame rates fps_23_976(), fps_29_97(), fps_47_952() or fps_59_94(),
//          guessExactFps(fps) returns the corresponding pre-defined frame
//          rate.  If fps is not close to one of the pre-defined frame rates,
//          then guessExactFps(fps) returns Rational(fps).
//
//-----------------------------------------------------------------------------

#include "ImfExport.h"
#include "ImfNamespace.h"

#include "ImfRational.h"

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_ENTER

inline Rational
fps_23_976 ()
{
    return Rational (24000, 1001);
}
inline Rational
fps_24 ()
{
    return Rational (24, 1);
}
inline Rational
fps_25 ()
{
    return Rational (25, 1);
}
inline Rational
fps_29_97 ()
{
    return Rational (30000, 1001);
}
inline Rational
fps_30 ()
{
    return Rational (30, 1);
}
inline Rational
fps_47_952 ()
{
    return Rational (48000, 1001);
}
inline Rational
fps_48 ()
{
    return Rational (48, 1);
}
inline Rational
fps_50 ()
{
    return Rational (50, 1);
}
inline Rational
fps_59_94 ()
{
    return Rational (60000, 1001);
}
inline Rational
fps_60 ()
{
    return Rational (60, 1);
}

IMF_EXPORT Rational guessExactFps (double fps);
IMF_EXPORT Rational guessExactFps (const Rational& fps);

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_EXIT

#endif