1 /////////////////////////////////////////////////////////////////////////// 2 // 3 // Copyright (c) 2004, Industrial Light & Magic, a division of Lucas 4 // Digital Ltd. LLC 5 // 6 // All rights reserved. 7 // 8 // Redistribution and use in source and binary forms, with or without 9 // modification, are permitted provided that the following conditions are 10 // met: 11 // * Redistributions of source code must retain the above copyright 12 // notice, this list of conditions and the following disclaimer. 13 // * Redistributions in binary form must reproduce the above 14 // copyright notice, this list of conditions and the following disclaimer 15 // in the documentation and/or other materials provided with the 16 // distribution. 17 // * Neither the name of Industrial Light & Magic nor the names of 18 // its contributors may be used to endorse or promote products derived 19 // from this software without specific prior written permission. 20 // 21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 24 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 25 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 27 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 // 33 /////////////////////////////////////////////////////////////////////////// 34 35 36 #ifndef INCLUDED_IMF_VERSION_H 37 #define INCLUDED_IMF_VERSION_H 38 39 //----------------------------------------------------------------------------- 40 // 41 // Magic and version number. 42 // 43 //----------------------------------------------------------------------------- 44 45 46 namespace Imf { 47 48 49 // 50 // The MAGIC number is stored in the first four bytes of every 51 // OpenEXR image file. This can be used to quickly test whether 52 // a given file is an OpenEXR image file (see isImfMagic(), below). 53 // 54 55 const int MAGIC = 20000630; 56 57 58 // 59 // The second item in each OpenEXR image file, right after the 60 // magic number, is a four-byte file version identifier. Depending 61 // on a file's version identifier, a file reader can enable various 62 // backwards-compatibility switches, or it can quickly reject files 63 // that it cannot read. 64 // 65 // The version identifier is split into an 8-bit version number, 66 // and a 24-bit flags field. 67 // 68 69 const int VERSION_NUMBER_FIELD = 0x000000ff; 70 const int VERSION_FLAGS_FIELD = 0xffffff00; 71 72 73 // 74 // Value that goes into VERSION_NUMBER_FIELD. 75 // 76 77 const int EXR_VERSION = 2; 78 79 80 // 81 // Flags that can go into VERSION_FLAGS_FIELD. 82 // Flags can only occupy the 1 bits in VERSION_FLAGS_FIELD. 83 // 84 85 const int TILED_FLAG = 0x00000200; // File is tiled 86 87 const int LONG_NAMES_FLAG = 0x00000400; // File contains long 88 // attribute or channel 89 // names 90 91 // 92 // Bitwise OR of all known flags. 93 // 94 95 const int ALL_FLAGS = TILED_FLAG | LONG_NAMES_FLAG; 96 97 98 // 99 // Utility functions 100 // 101 102 inline bool isTiled (int version) {return !!(version & TILED_FLAG);} 103 inline int makeTiled (int version) {return version | TILED_FLAG;} 104 inline int makeNotTiled (int version) {return version & ~TILED_FLAG;} 105 inline int getVersion (int version) {return version & VERSION_NUMBER_FIELD;} 106 inline int getFlags (int version) {return version & VERSION_FLAGS_FIELD;} 107 inline bool supportsFlags (int flags) {return !(flags & ~ALL_FLAGS);} 108 109 110 // 111 // Given the first four bytes of a file, returns true if the 112 // file is probably an OpenEXR image file, false if not. 113 // 114 115 bool isImfMagic (const char bytes[4]); 116 117 118 } // namespace Imf 119 120 #endif 121
