2022-04-07 18:46:57 +02:00

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C++

///////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2006, Industrial Light & Magic, a division of Lucas
// Digital Ltd. LLC
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Industrial Light & Magic nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
///////////////////////////////////////////////////////////////////////////
#ifndef INCLUDED_CTL_TO_LUT_H
#define INCLUDED_CTL_TO_LUT_H
//-----------------------------------------------------------------------------
//
// Run a set of CTL transforms to generate a color lookup table.
//
// Function ctlToLut() applies a series of CTL transforms to a
// set of input pixel values, pixelValues, producing a color lookup
// table, lut. A Cg shader in the display thread of the playexr
// program will use this lookup table to approximate the effect
// of applying the CTL transforms directly to the displayed images.
//
// Parameters:
//
// transformNames A list of the names of the CTL transforms that will
// be applied to the input pixel values. If this list
// is empty, ctlToLut() looks for a rendering transform
// and a display transform:
//
// If inHeader contains a string attribute called
// "renderingTransform" then the value of this attribute
// is the name of the rendering transform.
// If inHeader contains no such attribute, then the
// name of the rendering transform is "transform_RRT".
//
// If the environment variable CTL_DISPLAY_TRANSFORM
// is set, the value of the environment variable is
// the name of the display transform.
// If the environment variable is not set, then the name
// of the display transform is "transform_display_video".
//
// inHeader The header of the first frame of the image sequence
// displayed by playexr. The attributes in the header
// can be read by the CTL transforms.
//
// lutSize Number of elements in the pixelValues and lut arrays.
//
// pixelValues,
// lut Input and output pixel data arrays. Four channels
// R, G, B and A are interleaved: RGBARGBARGBA...
// The A channel is only for padding; it cannot be
// accessed by the CTL transforms.
//
//
// Function displayVideoGamma() returns 1/g, where g is the display's
// video gamma. The value of g is read from the environment variable
// EXR_DISPLAY_VIDEO_GAMMA. If the environment variable is not set,
// then displayVideoGamma() returns 1 / 2.2.
//
//-----------------------------------------------------------------------------
#include <ImfHeader.h>
#include <string>
#include <vector>
#include <half.h>
#include <cstdlib>
void
ctlToLut (std::vector<std::string> transformNames,
OPENEXR_IMF_NAMESPACE::Header inHeader,
size_t lutSize,
const half pixelValues[/*lutSize*/],
half lut[/*lutSize*/]);
float
displayVideoGamma ();
#endif