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///////////////////////////////////////////////////////////////////////////
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// Copyright (c) 2004, Industrial Light & Magic, a division of Lucas
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// All rights reserved.
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// * Neither the name of Industrial Light & Magic nor the names of
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// its contributors may be used to endorse or promote products derived
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// from this software without specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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///////////////////////////////////////////////////////////////////////////
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#ifndef INCLUDED_IMF_VERSION_H
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#define INCLUDED_IMF_VERSION_H
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//-----------------------------------------------------------------------------
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// Magic and version number.
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//-----------------------------------------------------------------------------
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// The MAGIC number is stored in the first four bytes of every
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// OpenEXR image file. This can be used to quickly test whether
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// a given file is an OpenEXR image file (see isImfMagic(), below).
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const int MAGIC = 20000630;
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// The second item in each OpenEXR image file, right after the
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// magic number, is a four-byte file version identifier. Depending
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// on a file's version identifier, a file reader can enable various
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// backwards-compatibility switches, or it can quickly reject files
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// that it cannot read.
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// The version identifier is split into an 8-bit version number,
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// and a 24-bit flags field.
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const int VERSION_NUMBER_FIELD = 0x000000ff;
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const int VERSION_FLAGS_FIELD = 0xffffff00;
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// Value that goes into VERSION_NUMBER_FIELD.
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const int EXR_VERSION = 2;
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// Flags that can go into VERSION_FLAGS_FIELD.
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// Flags can only occupy the 1 bits in VERSION_FLAGS_FIELD.
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const int TILED_FLAG = 0x00000200; // File is tiled
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const int LONG_NAMES_FLAG = 0x00000400; // File contains long
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// attribute or channel
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// Bitwise OR of all known flags.
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const int ALL_FLAGS = TILED_FLAG | LONG_NAMES_FLAG;
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inline bool isTiled (int version) {return !!(version & TILED_FLAG);}
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inline int makeTiled (int version) {return version | TILED_FLAG;}
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inline int makeNotTiled (int version) {return version & ~TILED_FLAG;}
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inline int getVersion (int version) {return version & VERSION_NUMBER_FIELD;}
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inline int getFlags (int version) {return version & VERSION_FLAGS_FIELD;}
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inline bool supportsFlags (int flags) {return !(flags & ~ALL_FLAGS);}
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// Given the first four bytes of a file, returns true if the
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// file is probably an OpenEXR image file, false if not.
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bool isImfMagic (const char bytes[4]);