// ========================================================== // Metadata functions implementation // Exif metadata model // // Design and implementation by // - Hervé Drolon (drolon@infonie.fr) // - Mihail Naydenov (mnaydenov@users.sourceforge.net) // - Garrick Meeker (garrickmeeker@users.sourceforge.net) // // Based on the following implementations: // - metadata-extractor : http://www.drewnoakes.com/code/exif/ // - jhead : http://www.sentex.net/~mwandel/jhead/ // - ImageMagick : http://www.imagemagick.org/ // // This file is part of FreeImage 3 // // COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY // OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES // THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE // OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED // CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT // THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY // SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL // PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER // THIS DISCLAIMER. // // Use at your own risk! // ========================================================== #ifdef _MSC_VER #pragma warning (disable : 4786) // identifier was truncated to 'number' characters #endif #include "../stdafx.h" #include "FreeImageTag.h" // ========================================================== // Exif JPEG routines // ========================================================== #define EXIF_NUM_FORMATS 12 #define TAG_EXIF_OFFSET 0x8769 // Exif IFD Pointer #define TAG_GPS_OFFSET 0x8825 // GPS Info IFD Pointer #define TAG_INTEROP_OFFSET 0xA005 // Interoperability IFD Pointer #define TAG_MAKER_NOTE 0x927C // Maker note // CANON cameras have some funny bespoke fields that need further processing... #define TAG_CANON_CAMERA_STATE_0x01 0x0001 // tags under tag 0x001 (CameraSettings) #define TAG_CANON_CAMERA_STATE_0x02 0x0002 // tags under tag 0x002 (FocalLength) #define TAG_CANON_CAMERA_STATE_0x04 0x0004 // tags under tag 0x004 (ShotInfo) #define TAG_CANON_CAMERA_STATE_0x12 0x0012 // tags under tag 0x012 (AFInfo) #define TAG_CANON_CAMERA_STATE_0xA0 0x00A0 // tags under tag 0x0A0 (ProcessingInfo) #define TAG_CANON_CAMERA_STATE_0xE0 0x00E0 // tags under tag 0x0E0 (SensorInfo) // ===================================================================== // Reimplementation of strnicmp (it is not supported on some systems) // ===================================================================== /** Compare characters of two strings without regard to case. @param s1 Null-terminated string to compare. @param s2 Null-terminated string to compare. @param len Number of characters to compare @return Returns 0 if s1 substring identical to s2 substring */ static int FreeImage_strnicmp(const char *s1, const char *s2, size_t len) { unsigned char c1, c2; if(!s1 || !s2) return -1; c1 = 0; c2 = 0; if(len) { do { c1 = *s1; c2 = *s2; s1++; s2++; if (!c1) break; if (!c2) break; if (c1 == c2) continue; c1 = (BYTE)tolower(c1); c2 = (BYTE)tolower(c2); if (c1 != c2) break; } while (--len); } return (int)c1 - (int)c2; } // ---------------------------------------------------------- // Little Endian / Big Endian io routines // ---------------------------------------------------------- static short ReadInt16(BOOL msb_order, const void *buffer) { short value; if(msb_order) { value = (short)((((BYTE*) buffer)[0] << 8) | ((BYTE*) buffer)[1]); return value; } value = (short)((((BYTE*) buffer)[1] << 8) | ((BYTE*) buffer)[0]); return value; } static LONG ReadInt32(BOOL msb_order, const void *buffer) { LONG value; if(msb_order) { value = (LONG)((((BYTE*) buffer)[0] << 24) | (((BYTE*) buffer)[1] << 16) | (((BYTE*) buffer)[2] << 8) | (((BYTE*) buffer)[3])); return value; } value = (LONG)((((BYTE*) buffer)[3] << 24) | (((BYTE*) buffer)[2] << 16) | (((BYTE*) buffer)[1] << 8 ) | (((BYTE*) buffer)[0])); return value; } static WORD ReadUint16(BOOL msb_order, const void *buffer) { WORD value; if(msb_order) { value = (WORD) ((((BYTE*) buffer)[0] << 8) | ((BYTE*) buffer)[1]); return value; } value = (WORD) ((((BYTE*) buffer)[1] << 8) | ((BYTE*) buffer)[0]); return value; } static DWORD ReadUint32(BOOL msb_order, const void *buffer) { return ((DWORD) ReadInt32(msb_order, buffer) & 0xFFFFFFFF); } // ---------------------------------------------------------- // Exif JPEG markers routines // ---------------------------------------------------------- /** Process a IFD offset Returns the offset and the metadata model for this tag */ static void processIFDOffset(FITAG *tag, const char *pval, BOOL msb_order, DWORD *subdirOffset, TagLib::MDMODEL *md_model) { // get the IFD offset *subdirOffset = ReadUint32(msb_order, pval); // select a tag info table switch(FreeImage_GetTagID(tag)) { case TAG_EXIF_OFFSET: *md_model = TagLib::EXIF_EXIF; break; case TAG_GPS_OFFSET: *md_model = TagLib::EXIF_GPS; break; case TAG_INTEROP_OFFSET: *md_model = TagLib::EXIF_INTEROP; break; } } /** Process a maker note IFD offset Returns the offset and the metadata model for this tag */ static void processMakerNote(FIBITMAP *dib, const char *pval, BOOL msb_order, DWORD *subdirOffset, TagLib::MDMODEL *md_model) { FITAG *tagMake = NULL; *subdirOffset = 0; *md_model = TagLib::UNKNOWN; // Determine the camera model and makernote format // WARNING: note that Maker may be NULL sometimes so check its value before using it // (NULL pointer checking is done by FreeImage_strnicmp) FreeImage_GetMetadata(FIMD_EXIF_MAIN, dib, "Make", &tagMake); const char *Maker = (char*)FreeImage_GetTagValue(tagMake); if((memcmp("OLYMP\x00\x01", pval, 7) == 0) || (memcmp("OLYMP\x00\x02", pval, 7) == 0) || (memcmp("EPSON", pval, 5) == 0) || (memcmp("AGFA", pval, 4) == 0)) { // Olympus Type 1 Makernote // Epson and Agfa use Olympus maker note standard, // see: http://www.ozhiker.com/electronics/pjmt/jpeg_info/ *md_model = TagLib::EXIF_MAKERNOTE_OLYMPUSTYPE1; *subdirOffset = 8; } else if(memcmp("OLYMPUS\x00\x49\x49\x03\x00", pval, 12) == 0) { // Olympus Type 2 Makernote // !!! NOT YET SUPPORTED !!! *subdirOffset = 0; *md_model = TagLib::UNKNOWN; } else if(memcmp("Nikon", pval, 5) == 0) { /* There are two scenarios here: * Type 1: * :0000: 4E 69 6B 6F 6E 00 01 00-05 00 02 00 02 00 06 00 Nikon........... * :0010: 00 00 EC 02 00 00 03 00-03 00 01 00 00 00 06 00 ................ * Type 3: * :0000: 4E 69 6B 6F 6E 00 02 00-00 00 4D 4D 00 2A 00 00 Nikon....MM.*... * :0010: 00 08 00 1E 00 01 00 07-00 00 00 04 30 32 30 30 ............0200 */ if (pval[6] == 1) { // Nikon type 1 Makernote *md_model = TagLib::EXIF_MAKERNOTE_NIKONTYPE1; *subdirOffset = 8; } else if (pval[6] == 2) { // Nikon type 3 Makernote *md_model = TagLib::EXIF_MAKERNOTE_NIKONTYPE3; *subdirOffset = 18; } else { // Unsupported makernote data ignored *subdirOffset = 0; *md_model = TagLib::UNKNOWN; } } else if(Maker && (FreeImage_strnicmp("NIKON", Maker, 5) == 0)) { // Nikon type 2 Makernote *md_model = TagLib::EXIF_MAKERNOTE_NIKONTYPE2; *subdirOffset = 0; } else if(Maker && (FreeImage_strnicmp("Canon", Maker, 5) == 0)) { // Canon Makernote *md_model = TagLib::EXIF_MAKERNOTE_CANON; *subdirOffset = 0; } else if(Maker && (FreeImage_strnicmp("Casio", Maker, 5) == 0)) { // Casio Makernote if(memcmp("QVC\x00\x00\x00", pval, 6) == 0) { // Casio Type 2 Makernote *md_model = TagLib::EXIF_MAKERNOTE_CASIOTYPE2; *subdirOffset = 6; } else { // Casio Type 1 Makernote *md_model = TagLib::EXIF_MAKERNOTE_CASIOTYPE1; *subdirOffset = 0; } } else if ((memcmp("FUJIFILM", pval, 8) == 0) || (Maker && (FreeImage_strnicmp("Fujifilm", Maker, 8) == 0))) { // Fujifile Makernote // Fujifilm's Makernote always use little-endian order altough the Exif section maybe in little-endian order or in big-endian order. // If msb_order == TRUE, the Makernote won't be read: // the value of ifdStart will be 0x0c000000 instead of 0x0000000c and the MakerNote section will be discarded later // in jpeg_read_exif_dir because the IFD is too high *md_model = TagLib::EXIF_MAKERNOTE_FUJIFILM; DWORD ifdStart = ReadUint32(msb_order, pval + 8); *subdirOffset = ifdStart; } else if(memcmp("KYOCERA\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x00\x00\x00", pval, 22) == 0) { *md_model = TagLib::EXIF_MAKERNOTE_KYOCERA; *subdirOffset = 22; } else if(Maker && (FreeImage_strnicmp("Minolta", Maker, 7) == 0)) { // Minolta maker note *md_model = TagLib::EXIF_MAKERNOTE_MINOLTA; *subdirOffset = 0; } else if(memcmp("Panasonic\x00\x00\x00", pval, 12) == 0) { // Panasonic maker note *md_model = TagLib::EXIF_MAKERNOTE_PANASONIC; *subdirOffset = 12; } else if(Maker && (FreeImage_strnicmp("LEICA", Maker, 5) == 0)) { // Leica maker note if(memcmp("LEICA\x00\x00\x00", pval, 8) == 0) { // not yet supported makernote data ignored *subdirOffset = 0; *md_model = TagLib::UNKNOWN; } } else if(Maker && ((FreeImage_strnicmp("Pentax", Maker, 6) == 0) || (FreeImage_strnicmp("Asahi", Maker, 5) == 0))) { // Pentax maker note if(memcmp("AOC\x00", pval, 4) == 0) { // Type 2 Pentax Makernote *md_model = TagLib::EXIF_MAKERNOTE_PENTAX; *subdirOffset = 6; } else { // Type 1 Pentax Makernote *md_model = TagLib::EXIF_MAKERNOTE_ASAHI; *subdirOffset = 0; } } else if((memcmp("SONY CAM\x20\x00\x00\x00", pval, 12) == 0) || (memcmp("SONY DSC\x20\x00\x00\x00", pval, 12) == 0)) { *md_model = TagLib::EXIF_MAKERNOTE_SONY; *subdirOffset = 12; } else if((memcmp("SIGMA\x00\x00\x00", pval, 8) == 0) || (memcmp("FOVEON\x00\x00", pval, 8) == 0)) { FITAG *tagModel = NULL; FreeImage_GetMetadata(FIMD_EXIF_MAIN, dib, "Model", &tagModel); const char *Model = (char*)FreeImage_GetTagValue(tagModel); if(Model && (memcmp("SIGMA SD1\x00", Model, 10) == 0)) { // Sigma SD1 maker note *subdirOffset = 10; *md_model = TagLib::EXIF_MAKERNOTE_SIGMA_SD1; } else { // Sigma / Foveon makernote *subdirOffset = 10; *md_model = TagLib::EXIF_MAKERNOTE_SIGMA_FOVEON; } } } /** Process a Canon maker note tag. A single Canon tag may contain many other tags within. */ static BOOL processCanonMakerNoteTag(FIBITMAP *dib, FITAG *tag) { char defaultKey[16]; DWORD startIndex = 0; TagLib& s = TagLib::instance(); WORD tag_id = FreeImage_GetTagID(tag); int subTagTypeBase = 0; switch(tag_id) { case TAG_CANON_CAMERA_STATE_0x01: subTagTypeBase = 0xC100; startIndex = 1; break; case TAG_CANON_CAMERA_STATE_0x02: subTagTypeBase = 0xC200; startIndex = 0; break; case TAG_CANON_CAMERA_STATE_0x04: subTagTypeBase = 0xC400; startIndex = 1; break; case TAG_CANON_CAMERA_STATE_0x12: subTagTypeBase = 0x1200; startIndex = 0; break; case TAG_CANON_CAMERA_STATE_0xA0: subTagTypeBase = 0xCA00; startIndex = 1; break; case TAG_CANON_CAMERA_STATE_0xE0: subTagTypeBase = 0xCE00; startIndex = 1; break; default: { // process as a normal tag // get the tag key and description const char *key = s.getTagFieldName(TagLib::EXIF_MAKERNOTE_CANON, tag_id, defaultKey); FreeImage_SetTagKey(tag, key); const char *description = s.getTagDescription(TagLib::EXIF_MAKERNOTE_CANON, tag_id); FreeImage_SetTagDescription(tag, description); // store the tag if(key) { FreeImage_SetMetadata(FIMD_EXIF_MAKERNOTE, dib, key, tag); } return TRUE; } break; } WORD *pvalue = (WORD*)FreeImage_GetTagValue(tag); // create a tag FITAG *canonTag = FreeImage_CreateTag(); if(!canonTag) return FALSE; // we intentionally skip the first array member (if needed) for (DWORD i = startIndex; i < FreeImage_GetTagCount(tag); i++) { tag_id = (WORD)(subTagTypeBase + i); FreeImage_SetTagID(canonTag, tag_id); FreeImage_SetTagType(canonTag, FIDT_SHORT); FreeImage_SetTagCount(canonTag, 1); FreeImage_SetTagLength(canonTag, 2); FreeImage_SetTagValue(canonTag, &pvalue[i]); // get the tag key and description const char *key = s.getTagFieldName(TagLib::EXIF_MAKERNOTE_CANON, tag_id, defaultKey); FreeImage_SetTagKey(canonTag, key); const char *description = s.getTagDescription(TagLib::EXIF_MAKERNOTE_CANON, tag_id); FreeImage_SetTagDescription(canonTag, description); // store the tag if(key) { FreeImage_SetMetadata(FIMD_EXIF_MAKERNOTE, dib, key, canonTag); } } // delete the tag FreeImage_DeleteTag(canonTag); return TRUE; } /** Process a standard Exif tag */ static void processExifTag(FIBITMAP *dib, FITAG *tag, char *pval, BOOL msb_order, TagLib::MDMODEL md_model) { char defaultKey[16]; int n; DWORD i; // allocate a buffer to store the tag value BYTE *exif_value = (BYTE*)malloc(FreeImage_GetTagLength(tag) * sizeof(BYTE)); if(NULL == exif_value) { // out of memory ... return; } memset(exif_value, 0, FreeImage_GetTagLength(tag) * sizeof(BYTE)); // get the tag value switch(FreeImage_GetTagType(tag)) { case FIDT_SHORT: { WORD *value = (WORD*)&exif_value[0]; for(i = 0; i < FreeImage_GetTagCount(tag); i++) { value[i] = ReadUint16(msb_order, pval + i * sizeof(WORD)); } FreeImage_SetTagValue(tag, value); break; } case FIDT_SSHORT: { short *value = (short*)&exif_value[0]; for(i = 0; i < FreeImage_GetTagCount(tag); i++) { value[i] = ReadInt16(msb_order, pval + i * sizeof(short)); } FreeImage_SetTagValue(tag, value); break; } case FIDT_LONG: { DWORD *value = (DWORD*)&exif_value[0]; for(i = 0; i < FreeImage_GetTagCount(tag); i++) { value[i] = ReadUint32(msb_order, pval + i * sizeof(DWORD)); } FreeImage_SetTagValue(tag, value); break; } case FIDT_SLONG: { LONG *value = (LONG*)&exif_value[0]; for(i = 0; i < FreeImage_GetTagCount(tag); i++) { value[i] = ReadInt32(msb_order, pval + i * sizeof(LONG)); } FreeImage_SetTagValue(tag, value); break; } case FIDT_RATIONAL: { n = sizeof(DWORD); DWORD *value = (DWORD*)&exif_value[0]; for(i = 0; i < 2 * FreeImage_GetTagCount(tag); i++) { // read a sequence of (numerator, denominator) value[i] = ReadUint32(msb_order, n*i + (char*)pval); } FreeImage_SetTagValue(tag, value); break; } case FIDT_SRATIONAL: { n = sizeof(LONG); LONG *value = (LONG*)&exif_value[0]; for(i = 0; i < 2 * FreeImage_GetTagCount(tag); i++) { // read a sequence of (numerator, denominator) value[i] = ReadInt32(msb_order, n*i + (char*)pval); } FreeImage_SetTagValue(tag, value); break; } case FIDT_BYTE: case FIDT_ASCII: case FIDT_SBYTE: case FIDT_UNDEFINED: case FIDT_FLOAT: case FIDT_DOUBLE: default: FreeImage_SetTagValue(tag, pval); break; } if(md_model == TagLib::EXIF_MAKERNOTE_CANON) { // A single Canon tag can have multiple values within processCanonMakerNoteTag(dib, tag); } else { TagLib& s = TagLib::instance(); WORD tag_id = FreeImage_GetTagID(tag); // get the tag key and description const char *key = s.getTagFieldName(md_model, tag_id, defaultKey); FreeImage_SetTagKey(tag, key); const char *description = s.getTagDescription(md_model, tag_id); FreeImage_SetTagDescription(tag, description); // store the tag if(key) { FreeImage_SetMetadata(s.getFreeImageModel(md_model), dib, key, tag); } } // free the temporary buffer free(exif_value); } /** Process Exif directory @param dib Input FIBITMAP @param tiffp Pointer to the TIFF header @param dwOffsetIfd0 Offset to the 0th IFD (first IFD) @param dwLength Length of the Exif file @param dwProfileOffset File offset to be used when reading 'offset/value' tags @param msb_order Endianness order of the Exif file (TRUE if big-endian, FALSE if little-endian) @param starting_md_model Metadata model of the IFD (should be TagLib::EXIF_MAIN for a jpeg) @return Returns TRUE if sucessful, returns FALSE otherwise */ static BOOL jpeg_read_exif_dir(FIBITMAP *dib, const BYTE *tiffp, DWORD dwOffsetIfd0, DWORD dwLength, DWORD dwProfileOffset, BOOL msb_order, TagLib::MDMODEL starting_md_model) { WORD de, nde; std::stack destack; // directory entries stack std::stack ifdstack; // IFD stack std::stack modelstack; // metadata model stack // Keep a list of already visited IFD to avoid stack overflows // when recursive/cyclic directory structures exist. // This kind of recursive Exif file was encountered with Kodak images coming from // KODAK PROFESSIONAL DCS Photo Desk JPEG Export v3.2 W std::map visitedIFD; /* "An Image File Directory (IFD) consists of a 2-byte count of the number of directory entries (i.e. the number of fields), followed by a sequence of 12-byte field entries, followed by a 4-byte offset of the next IFD (or 0 if none)." The "next IFD" (1st IFD) is the thumbnail. */ #define DIR_ENTRY_ADDR(_start, _entry) (_start + 2 + (12 * _entry)) // set the metadata model to Exif TagLib::MDMODEL md_model = starting_md_model; // set the pointer to the first IFD (0th IFD) and follow it were it leads. const BYTE *ifd0th = (BYTE*)tiffp + (size_t)dwOffsetIfd0; const BYTE *ifdp = ifd0th; de = 0; do { // if there is anything on the stack then pop it off if(!destack.empty()) { ifdp = ifdstack.top(); ifdstack.pop(); de = destack.top(); destack.pop(); md_model = modelstack.top(); modelstack.pop(); } // remember that we've visited this directory and entry so that we don't visit it again later DWORD visited = (DWORD)( (((size_t)ifdp & 0xFFFF) << 16) | (size_t)de ); if(visitedIFD.find(visited) != visitedIFD.end()) { continue; } else { visitedIFD[visited] = 1; // processed } // determine how many entries there are in the current IFD nde = ReadUint16(msb_order, ifdp); if (((size_t)(ifdp - tiffp) + 12 * nde) > (size_t)dwLength) { // suspicious IFD offset, ignore continue; } for(; de < nde; de++) { char *pde = NULL; // pointer to the directory entry char *pval = NULL; // pointer to the tag value // create a tag FITAG *tag = FreeImage_CreateTag(); if(!tag) return FALSE; // point to the directory entry pde = (char*) DIR_ENTRY_ADDR(ifdp, de); // get the tag ID WORD tag_id = ReadUint16(msb_order, pde); FreeImage_SetTagID(tag, tag_id); // get the tag type WORD tag_type = (WORD)ReadUint16(msb_order, pde + 2); if((tag_type - 1) >= EXIF_NUM_FORMATS) { // a problem occured : delete the tag (not free'd after) FreeImage_DeleteTag(tag); // break out of the for loop break; } FreeImage_SetTagType(tag, (FREE_IMAGE_MDTYPE)tag_type); // get number of components DWORD tag_count = ReadUint32(msb_order, pde + 4); FreeImage_SetTagCount(tag, tag_count); // check that tag length (size of the tag value in bytes) will fit in a DWORD unsigned tag_data_width = FreeImage_TagDataWidth(FreeImage_GetTagType(tag)); if (tag_data_width != 0 && FreeImage_GetTagCount(tag) > ~(DWORD)0 / tag_data_width) { FreeImage_DeleteTag(tag); // jump to next entry continue; } FreeImage_SetTagLength(tag, FreeImage_GetTagCount(tag) * tag_data_width); if(FreeImage_GetTagLength(tag) <= 4) { // 4 bytes or less and value is in the dir entry itself pval = pde + 8; } else { // if its bigger than 4 bytes, the directory entry contains an offset DWORD offset_value = ReadUint32(msb_order, pde + 8); // the offset can be relative to tiffp or to an external reference (see JPEG-XR) if(dwProfileOffset) { offset_value -= dwProfileOffset; } // first check if offset exceeds buffer, at this stage FreeImage_GetTagLength may return invalid data if(offset_value > dwLength) { // a problem occured : delete the tag (not free'd after) FreeImage_DeleteTag(tag); // jump to next entry continue; } // now check that length does not exceed the buffer size if(FreeImage_GetTagLength(tag) > dwLength - offset_value){ // a problem occured : delete the tag (not free'd after) FreeImage_DeleteTag(tag); // jump to next entry continue; } pval = (char*)(tiffp + offset_value); } // check for a IFD offset BOOL isIFDOffset = FALSE; switch(FreeImage_GetTagID(tag)) { case TAG_EXIF_OFFSET: case TAG_GPS_OFFSET: case TAG_INTEROP_OFFSET: case TAG_MAKER_NOTE: isIFDOffset = TRUE; break; } if(isIFDOffset) { DWORD sub_offset = 0; TagLib::MDMODEL next_mdmodel = md_model; const BYTE *next_ifd = ifdp; // get offset and metadata model if (FreeImage_GetTagID(tag) == TAG_MAKER_NOTE) { processMakerNote(dib, pval, msb_order, &sub_offset, &next_mdmodel); next_ifd = (BYTE*)pval + sub_offset; } else { processIFDOffset(tag, pval, msb_order, &sub_offset, &next_mdmodel); next_ifd = (BYTE*)tiffp + sub_offset; } if((sub_offset < dwLength) && (next_mdmodel != TagLib::UNKNOWN)) { // push our current directory state onto the stack ifdstack.push(ifdp); // jump to the next entry de++; destack.push(de); // push our current metadata model modelstack.push(md_model); // push new state onto of stack to cause a jump ifdstack.push(next_ifd); destack.push(0); // select a new metadata model modelstack.push(next_mdmodel); // delete the tag as it won't be stored nor deleted in the for() loop FreeImage_DeleteTag(tag); break; // break out of the for loop } else { // unsupported camera model, canon maker tag or something unknown // process as a standard tag processExifTag(dib, tag, pval, msb_order, md_model); } } else { // process as a standard tag processExifTag(dib, tag, pval, msb_order, md_model); } // delete the tag FreeImage_DeleteTag(tag); } // for(nde) // additional thumbnail data is skipped } while (!destack.empty()); // // --- handle thumbnail data --- // const WORD entriesCount0th = ReadUint16(msb_order, ifd0th); DWORD next_offset = ReadUint32(msb_order, DIR_ENTRY_ADDR(ifd0th, entriesCount0th)); if((next_offset == 0) || (next_offset >= dwLength)) { return TRUE; //< no thumbnail } const BYTE* const ifd1st = (BYTE*)tiffp + next_offset; const WORD entriesCount1st = ReadUint16(msb_order, ifd1st); unsigned thCompression = 0; unsigned thOffset = 0; unsigned thSize = 0; for(int e = 0; e < entriesCount1st; e++) { // point to the directory entry const BYTE* base = DIR_ENTRY_ADDR(ifd1st, e); // check for buffer overflow const size_t remaining = (size_t)base + 12 - (size_t)tiffp; if(remaining >= dwLength) { // bad IFD1 directory, ignore it return FALSE; } // get the tag ID WORD tag = ReadUint16(msb_order, base); // get the tag type /*WORD type = */ReadUint16(msb_order, base + sizeof(WORD)); // get number of components /*DWORD count = */ReadUint32(msb_order, base + sizeof(WORD) + sizeof(WORD)); // get the tag value DWORD offset = ReadUint32(msb_order, base + sizeof(WORD) + sizeof(WORD) + sizeof(DWORD)); switch(tag) { case TAG_COMPRESSION: // Tiff Compression Tag (should be COMPRESSION_OJPEG (6), but is not always respected) thCompression = offset; break; case TAG_JPEG_INTERCHANGE_FORMAT: // Tiff JPEGInterchangeFormat Tag thOffset = offset; break; case TAG_JPEG_INTERCHANGE_FORMAT_LENGTH: // Tiff JPEGInterchangeFormatLength Tag thSize = offset; break; // ### X and Y Resolution ignored, orientation ignored case TAG_X_RESOLUTION: // XResolution case TAG_Y_RESOLUTION: // YResolution case TAG_RESOLUTION_UNIT: // ResolutionUnit case TAG_ORIENTATION: // Orientation break; default: break; } } if(/*thCompression != 6 ||*/ thOffset == 0 || thSize == 0) { return TRUE; } if(thOffset + thSize > dwLength) { return TRUE; } // load the thumbnail const BYTE *thLocation = tiffp + thOffset; FIMEMORY* hmem = FreeImage_OpenMemory(const_cast(thLocation), thSize); FIBITMAP* thumbnail = FreeImage_LoadFromMemory(FIF_JPEG, hmem); FreeImage_CloseMemory(hmem); // store the thumbnail FreeImage_SetThumbnail(dib, thumbnail); // then delete it FreeImage_Unload(thumbnail); return TRUE; } // -------------------------------------------------------------------------- /** Read and decode JPEG_APP1 marker (Exif profile) @param dib Input FIBITMAP @param data Pointer to the APP1 marker @param length APP1 marker length @return Returns TRUE if successful, FALSE otherwise */ BOOL jpeg_read_exif_profile(FIBITMAP *dib, const BYTE *data, unsigned length) { // marker identifying string for Exif = "Exif\0\0" BYTE exif_signature[6] = { 0x45, 0x78, 0x69, 0x66, 0x00, 0x00 }; BYTE lsb_first[4] = { 0x49, 0x49, 0x2A, 0x00 }; // Classic TIFF signature - little-endian order BYTE msb_first[4] = { 0x4D, 0x4D, 0x00, 0x2A }; // Classic TIFF signature - big-endian order // profile size is up to 32-bit DWORD dwProfileLength = (DWORD)length; BYTE *pbProfile = (BYTE*)data; // verify the identifying string if(memcmp(exif_signature, pbProfile, sizeof(exif_signature)) == 0) { // This is an Exif profile // should contain a TIFF header with up to 2 IFDs (IFD stands for 'Image File Directory') // 0th IFD : the image attributes, 1st IFD : may be used for thumbnail pbProfile += sizeof(exif_signature); dwProfileLength -= sizeof(exif_signature); // read the TIFF header (8 bytes) // check the endianess order BOOL bBigEndian = TRUE; if(memcmp(pbProfile, lsb_first, sizeof(lsb_first)) == 0) { // Exif section is in little-endian order bBigEndian = FALSE; } else { if(memcmp(pbProfile, msb_first, sizeof(msb_first)) == 0) { // Exif section is in big-endian order bBigEndian = TRUE; } else { // Invalid Exif alignment marker return FALSE; } } // this is the offset to the first IFD (Image File Directory) DWORD dwFirstOffset = ReadUint32(bBigEndian, pbProfile + 4); if (dwFirstOffset > dwProfileLength) { // bad Exif data return FALSE; } /* Note: as FreeImage 3.14.0, this test is no longer needed for images with similar suspicious offset => tested with Pentax Optio 230, FujiFilm SP-2500 and Canon EOS 300D if (dwFirstOffset < 8 || dwFirstOffset > 16) { // This is usually set to 8 // but PENTAX Optio 230 has it set differently, and uses it as offset. FreeImage_OutputMessageProc(FIF_JPEG, "Exif: Suspicious offset of first IFD value"); return FALSE; } */ // process Exif directories, starting with Exif-TIFF IFD return jpeg_read_exif_dir(dib, pbProfile, dwFirstOffset, dwProfileLength, 0, bBigEndian, TagLib::EXIF_MAIN); } return FALSE; } // ========================================================== // Exif JPEG helper routines // ========================================================== /** Read JPEG_APP1 marker (Exif profile) @param dib Input FIBITMAP @param dataptr Pointer to the APP1 marker @param datalen APP1 marker length @return Returns TRUE if successful, FALSE otherwise */ BOOL jpeg_read_exif_profile_raw(FIBITMAP *dib, const BYTE *profile, unsigned length) { // marker identifying string for Exif = "Exif\0\0" BYTE exif_signature[6] = { 0x45, 0x78, 0x69, 0x66, 0x00, 0x00 }; // verify the identifying string if(memcmp(exif_signature, profile, sizeof(exif_signature)) != 0) { // not an Exif profile return FALSE; } // create a tag FITAG *tag = FreeImage_CreateTag(); if(tag) { FreeImage_SetTagKey(tag, g_TagLib_ExifRawFieldName); FreeImage_SetTagLength(tag, (DWORD)length); FreeImage_SetTagCount(tag, (DWORD)length); FreeImage_SetTagType(tag, FIDT_BYTE); FreeImage_SetTagValue(tag, profile); // store the tag FreeImage_SetMetadata(FIMD_EXIF_RAW, dib, FreeImage_GetTagKey(tag), tag); // destroy the tag FreeImage_DeleteTag(tag); return TRUE; } return FALSE; } // ========================================================== // Exif JPEG-XR helper routines // ========================================================== /** Read and decode JPEG-XR Exif IFD @param dib Input FIBITMAP @param profile Pointer to the Exif marker @param length Exif marker length @param file_offset Reference offset in the original file of each tag value whose length is > 4 @return Returns TRUE if successful, FALSE otherwise */ BOOL jpegxr_read_exif_profile(FIBITMAP *dib, const BYTE *profile, unsigned length, unsigned file_offset) { // assume Little Endian order BOOL bBigEndian = FALSE; // process Exif specific IFD return jpeg_read_exif_dir(dib, profile, 0, length, file_offset, bBigEndian, TagLib::EXIF_EXIF); } /** Read and decode JPEG-XR Exif-GPS IFD @param dib Input FIBITMAP @param profile Pointer to the Exif-GPS profile @param length Exif-GPS profile length @param file_offset Reference offset in the original file of each tag value whose length is > 4 @return Returns TRUE if successful, FALSE otherwise */ BOOL jpegxr_read_exif_gps_profile(FIBITMAP *dib, const BYTE *profile, unsigned length, unsigned file_offset) { // assume Little Endian order BOOL bBigEndian = FALSE; // process Exif GPS IFD return jpeg_read_exif_dir(dib, profile, 0, length, file_offset, bBigEndian, TagLib::EXIF_GPS); } // ========================================================== // Exif common helper routines // ========================================================== /** Rotate a dib according to Exif info @param dib Input / Output dib to rotate @see PluginJPEG.cpp */ void RotateExif(FIBITMAP **dib) { // check for Exif rotation if(FreeImage_GetMetadataCount(FIMD_EXIF_MAIN, *dib)) { FIBITMAP *rotated = NULL; // process Exif rotation FITAG *tag = NULL; FreeImage_GetMetadata(FIMD_EXIF_MAIN, *dib, "Orientation", &tag); if((tag != NULL) && (FreeImage_GetTagID(tag) == TAG_ORIENTATION)) { const WORD orientation = *((WORD *)FreeImage_GetTagValue(tag)); switch (orientation) { case 1: // "top, left side" => 0° break; case 2: // "top, right side" => flip left-right FreeImage_FlipHorizontal(*dib); break; case 3: // "bottom, right side" => -180° rotated = FreeImage_Rotate(*dib, 180); FreeImage_Unload(*dib); *dib = rotated; break; case 4: // "bottom, left side" => flip up-down FreeImage_FlipVertical(*dib); break; case 5: // "left side, top" => +90° + flip up-down rotated = FreeImage_Rotate(*dib, 90); FreeImage_Unload(*dib); *dib = rotated; FreeImage_FlipVertical(*dib); break; case 6: // "right side, top" => -90° rotated = FreeImage_Rotate(*dib, -90); FreeImage_Unload(*dib); *dib = rotated; break; case 7: // "right side, bottom" => -90° + flip up-down rotated = FreeImage_Rotate(*dib, -90); FreeImage_Unload(*dib); *dib = rotated; FreeImage_FlipVertical(*dib); break; case 8: // "left side, bottom" => +90° rotated = FreeImage_Rotate(*dib, 90); FreeImage_Unload(*dib); *dib = rotated; break; default: break; } } } } // ========================================================== // Exif TIFF JPEG-XR helper routines // ========================================================== class PredicateTagIDCompare { public: bool operator()(FITAG *a, FITAG *b) { WORD tag_id_a = FreeImage_GetTagID(a); WORD tag_id_b = FreeImage_GetTagID(b); return (tag_id_a < tag_id_b); } }; /** Write a metadata model as a TIF IFD to a FIMEMORY handle. The entries in the TIF IFD are sorted in ascending order by tag id. The last entry is written as 0 (4 bytes) which means no more IFD to follow. Supported metadata models are
  • FIMD_EXIF_MAIN
  • FIMD_EXIF_EXIF
  • FIMD_EXIF_GPS
  • FIMD_EXIF_INTEROP
The end of the buffer is filled with 4 bytes equal to 0 (end of IFD offset) @param dib Input FIBITMAP @param md_model Metadata model to write @param hmem Memory handle @return Returns TRUE if successful, FALSE otherwise @see tiff_get_ifd_profile */ static BOOL tiff_write_ifd(FIBITMAP *dib, FREE_IMAGE_MDMODEL md_model, FIMEMORY *hmem) { FITAG *tag = NULL; FIMETADATA *mdhandle = NULL; std::vector vTagList; TagLib::MDMODEL internal_md_model; DWORD ifd_offset = 0; // WORD-aligned IFD value offset const BYTE empty_byte = 0; // start of the file const long start_of_file = FreeImage_TellMemory(hmem); // get the metadata count unsigned metadata_count = FreeImage_GetMetadataCount(md_model, dib); if(metadata_count == 0) { return FALSE; } TagLib& s = TagLib::instance(); // check for supported metadata models switch(md_model) { case FIMD_EXIF_MAIN: internal_md_model = TagLib::EXIF_MAIN; break; case FIMD_EXIF_EXIF: internal_md_model = TagLib::EXIF_EXIF; break; case FIMD_EXIF_GPS: internal_md_model = TagLib::EXIF_GPS; break; case FIMD_EXIF_INTEROP: internal_md_model = TagLib::EXIF_INTEROP; break; default: return FALSE; } try { // 1) according to the TIFF specifications, // the entries in a TIF IFD must be sorted in ascending order by tag id // store the tags into a vector vTagList.reserve(metadata_count); mdhandle = FreeImage_FindFirstMetadata(md_model, dib, &tag); if(mdhandle) { // parse the tags and store them inside vTagList do { // rewrite the tag id using FreeImage internal database // (in case the tag id is wrong or missing) const char *key = FreeImage_GetTagKey(tag); int tag_id = s.getTagID(internal_md_model, key); if(tag_id != -1) { // this is a known tag, set the tag ID FreeImage_SetTagID(tag, (WORD)tag_id); // record the tag vTagList.push_back(tag); } // else ignore this tag } while(FreeImage_FindNextMetadata(mdhandle, &tag)); FreeImage_FindCloseMetadata(mdhandle); // sort the vector by tag id std::sort(vTagList.begin(), vTagList.end(), PredicateTagIDCompare()); // update the metadata_count metadata_count = (unsigned)vTagList.size(); } else { throw(1); } // 2) prepare the place for each IFD entries. /* An Image File Directory (IFD) consists of a 2-byte count of the number of directory entries (i.e., the number of fields), followed by a sequence of 12-byte field entries, followed by a 4-byte offset of the next IFD (or 0 if none). Do not forget to write the 4 bytes of 0 after the last IFD. */ { // prepare place for 2 bytes for number of entries + 12 bytes for each entry unsigned ifd_size = 2 + 12 * metadata_count; FreeImage_WriteMemory(&empty_byte, 1, ifd_size, hmem); // record the offset used to write values > 4-bytes ifd_offset = FreeImage_TellMemory(hmem); // rewind FreeImage_SeekMemory(hmem, start_of_file, SEEK_SET); } // 3) write each IFD entry in tag id ascending order // number of directory entries WORD nde = (WORD)metadata_count; FreeImage_WriteMemory(&nde, 1, 2, hmem); // for each entry ... for(unsigned i = 0; i < metadata_count; i++) { FITAG *tag = vTagList[i]; // tag id WORD tag_id = FreeImage_GetTagID(tag); FreeImage_WriteMemory(&tag_id, 1, 2, hmem); // tag type (compliant with TIFF specification) WORD tag_type = (WORD)FreeImage_GetTagType(tag); FreeImage_WriteMemory(&tag_type, 1, 2, hmem); // tag count DWORD tag_count = FreeImage_GetTagCount(tag); FreeImage_WriteMemory(&tag_count, 1, 4, hmem); // tag value or offset (results are in BYTE's units) unsigned tag_length = FreeImage_GetTagLength(tag); if(tag_length <= 4) { // 4 bytes or less, write the value (left justified) const BYTE *tag_value = (BYTE*)FreeImage_GetTagValue(tag); FreeImage_WriteMemory(tag_value, 1, tag_length, hmem); for(unsigned k = tag_length; k < 4; k++) { FreeImage_WriteMemory(&empty_byte, 1, 1, hmem); } } else { // write an offset FreeImage_WriteMemory(&ifd_offset, 1, 4, hmem); // write the value long current_position = FreeImage_TellMemory(hmem); FreeImage_SeekMemory(hmem, ifd_offset, SEEK_SET); FreeImage_WriteMemory(FreeImage_GetTagValue(tag), 1, tag_length, hmem); if(tag_length & 1) { // align to the next WORD boundary FreeImage_WriteMemory(&empty_byte, 1, 1, hmem); } // next offset to use ifd_offset = FreeImage_TellMemory(hmem); // rewind FreeImage_SeekMemory(hmem, current_position, SEEK_SET); } } // end-of-IFD or next IFD (0 == none) FreeImage_SeekMemory(hmem, ifd_offset, SEEK_SET); FreeImage_WriteMemory(&empty_byte, 1, 4, hmem); return TRUE; } catch(int) { return FALSE; } } /** Write a metadata model as a TIF IFD, returns the IFD as a buffer. The buffer is allocated by the function and must be freed by the caller, using 'free'. @param dib Input FIBITMAP @param md_model Metadata model to write @param ppbProfile Returned buffer @param uProfileLength Returned buffer size @return Returns TRUE if successful, FALSE otherwise @see tiff_write_ifd */ BOOL tiff_get_ifd_profile(FIBITMAP *dib, FREE_IMAGE_MDMODEL md_model, BYTE **ppbProfile, unsigned *uProfileLength) { FIMEMORY *hmem = NULL; try { // open a memory stream hmem = FreeImage_OpenMemory(NULL, 0); if(!hmem) { throw(1); } // write the metadata model as a TIF IFD BOOL bResult = tiff_write_ifd(dib, md_model, hmem); if(bResult) { BYTE *data = NULL; DWORD size_in_bytes = 0; // get a pointer to the stream buffer FreeImage_AcquireMemory(hmem, &data, &size_in_bytes); // (re-)allocate output buffer BYTE *pbProfile = *ppbProfile; pbProfile = (BYTE*)realloc(pbProfile, size_in_bytes); if(!pbProfile) { throw(1); } else { // copy IFD memcpy(pbProfile, data, size_in_bytes); *ppbProfile = pbProfile; *uProfileLength = size_in_bytes; } } // free the memory stream FreeImage_CloseMemory(hmem); return bResult; } catch(int) { FreeImage_CloseMemory(hmem); return FALSE; } } // ---------------------------------------------------------- // Exif PSD routines // ---------------------------------------------------------- /** Read and decode PSD image resource (Exif profile) @param dib Input FIBITMAP @param data Pointer to the resource data @param length Resource length @return Returns TRUE if successful, FALSE otherwise */ BOOL psd_read_exif_profile(FIBITMAP *dib, const BYTE *data, unsigned int length) { BYTE lsb_first[4] = { 0x49, 0x49, 0x2A, 0x00 }; // Classic TIFF signature - little-endian order BYTE msb_first[4] = { 0x4D, 0x4D, 0x00, 0x2A }; // Classic TIFF signature - big-endian order // profile size is up to 32-bit DWORD dwProfileLength = (DWORD)length; BYTE *pbProfile = (BYTE*)data; // This is an Exif profile // should contain a TIFF header with up to 2 IFDs (IFD stands for 'Image File Directory') // 0th IFD : the image attributes, 1st IFD : may be used for thumbnail // read the TIFF header (8 bytes) // check the endianess order BOOL bBigEndian = TRUE; if(memcmp(pbProfile, lsb_first, sizeof(lsb_first)) == 0) { // Exif section is in little-endian order bBigEndian = FALSE; } else { if(memcmp(pbProfile, msb_first, sizeof(msb_first)) == 0) { // Exif section is in big-endian order bBigEndian = TRUE; } else { // Invalid Exif alignment marker return FALSE; } } // this is the offset to the first IFD (Image File Directory) DWORD dwFirstOffset = ReadUint32(bBigEndian, pbProfile + 4); if (dwFirstOffset > dwProfileLength) { // bad Exif data return FALSE; } // process Exif directories, starting with Exif-TIFF IFD return jpeg_read_exif_dir(dib, pbProfile, dwFirstOffset, dwProfileLength, 0, bBigEndian, TagLib::EXIF_MAIN); } /** Read PSD image resource (Exif profile) @param dib Input FIBITMAP @param dataptr Pointer to the resource data @param datalen Resource length @return Returns TRUE if successful, FALSE otherwise */ BOOL psd_read_exif_profile_raw(FIBITMAP *dib, const BYTE *profile, unsigned length) { // marker identifying string for Exif = "Exif\0\0" // used by JPEG not PSD BYTE exif_signature[6] = { 0x45, 0x78, 0x69, 0x66, 0x00, 0x00 }; if(NULL == profile || length == 0) { return FALSE; } DWORD dwProfileLength = (DWORD)length + sizeof(exif_signature); BYTE *pbProfile = (BYTE*)malloc(dwProfileLength); if(NULL == pbProfile) { // out of memory ... return FALSE; } memcpy(pbProfile, exif_signature, sizeof(exif_signature)); memcpy(pbProfile + sizeof(exif_signature), profile, length); // create a tag FITAG *tag = FreeImage_CreateTag(); BOOL bSuccess = FALSE; if(tag) { FreeImage_SetTagKey(tag, g_TagLib_ExifRawFieldName); FreeImage_SetTagLength(tag, dwProfileLength); FreeImage_SetTagCount(tag, dwProfileLength); FreeImage_SetTagType(tag, FIDT_BYTE); FreeImage_SetTagValue(tag, pbProfile); // store the tag FreeImage_SetMetadata(FIMD_EXIF_RAW, dib, FreeImage_GetTagKey(tag), tag); // destroy the tag FreeImage_DeleteTag(tag); bSuccess = TRUE; } free(pbProfile); return bSuccess; }