9 #include <netinet/in.h>
11 #include <cctype> // for isalpha
16 #define HEADER_LENGTH_TO_READ 256 // on ne lit plus que le debut
21 struct FileReadError {
22 FileReadError(FILE* fp, const char* Mesg) {
24 dbg.Verbose(1, "EOF encountered :", Mesg);
26 dbg.Verbose(1, "Error on reading :", Mesg);
31 //FIXME: this looks dirty to me...
33 #define str2num(str, typeNum) *((typeNum *)(str))
35 // str est un pointeur dans un tableau de caractères, qui doit contenir,
36 // à cet endroit la, la représentation binaire d'un entier (16 ou 32 bits)
37 // je veux récupérer ça ... dans un entier.
38 // s'il y a une autre solution, évitant des cast et les indirections,
41 VRHT * gdcmHeader::dicom_vr = (VRHT*)0;
42 gdcmDictSet* gdcmHeader::Dicts = new gdcmDictSet();
44 void gdcmHeader::Initialise(void) {
45 if (!gdcmHeader::dicom_vr)
47 RefPubDict = gdcmHeader::Dicts->GetDefaultPublicDict();
48 RefShaDict = (gdcmDict*)0;
51 gdcmHeader::gdcmHeader (const char* InFilename) {
52 SetMaxSizeLoadElementValue(1024);
53 filename = InFilename;
55 fp=fopen(InFilename,"rw");
56 dbg.Error(!fp, "gdcmHeader::gdcmHeader cannot open file", InFilename);
60 gdcmHeader::~gdcmHeader (void) {
65 void gdcmHeader::InitVRDict (void) {
67 dbg.Verbose(0, "gdcmHeader::InitVRDict:", "VR dictionary allready set");
71 (*vr)["AE"] = "Application Entity"; // At most 16 bytes
72 (*vr)["AS"] = "Age String"; // Exactly 4 bytes
73 (*vr)["AT"] = "Attribute Tag"; // 2 16-bit unsigned short integers
74 (*vr)["CS"] = "Code String"; // At most 16 bytes
75 (*vr)["DA"] = "Date"; // Exactly 8 bytes
76 (*vr)["DS"] = "Decimal String"; // At most 16 bytes
77 (*vr)["DT"] = "Date Time"; // At most 26 bytes
78 (*vr)["FL"] = "Floating Point Single"; // 32-bit IEEE 754:1985 float
79 (*vr)["FD"] = "Floating Point Double"; // 64-bit IEEE 754:1985 double
80 (*vr)["IS"] = "Integer String"; // At most 12 bytes
81 (*vr)["LO"] = "Long String"; // At most 64 chars
82 (*vr)["LT"] = "Long Text"; // At most 10240 chars
83 (*vr)["OB"] = "Other Byte String"; // String of bytes (vr independant)
84 (*vr)["OW"] = "Other Word String"; // String of 16-bit words (vr dep)
85 (*vr)["PN"] = "Person Name"; // At most 64 chars
86 (*vr)["SH"] = "Short String"; // At most 16 chars
87 (*vr)["SL"] = "Signed Long"; // Exactly 4 bytes
88 (*vr)["SQ"] = "Sequence of Items"; // Not Applicable
89 (*vr)["SS"] = "Signed Short"; // Exactly 2 bytes
90 (*vr)["ST"] = "Short Text"; // At most 1024 chars
91 (*vr)["TM"] = "Time"; // At most 16 bytes
92 (*vr)["UI"] = "Unique Identifier"; // At most 64 bytes
93 (*vr)["UL"] = "Unsigned Long "; // Exactly 4 bytes
94 (*vr)["UN"] = "Unknown"; // Any length of bytes
95 (*vr)["US"] = "Unsigned Short "; // Exactly 2 bytes
96 (*vr)["UT"] = "Unlimited Text"; // At most 2^32 -1 chars
101 * \ingroup gdcmHeader
102 * \brief Discover what the swap code is (among little endian, big endian,
103 * bad little endian, bad big endian).
106 void gdcmHeader::CheckSwap()
108 // The only guaranted way of finding the swap code is to find a
109 // group tag since we know it's length has to be of four bytes i.e.
110 // 0x00000004. Finding the swap code in then straigthforward. Trouble
111 // occurs when we can't find such group...
113 guint32 x=4; // x : pour ntohs
114 bool net2host; // true when HostByteOrder is the same as NetworkByteOrder
118 char deb[HEADER_LENGTH_TO_READ];
120 // First, compare HostByteOrder and NetworkByteOrder in order to
121 // determine if we shall need to swap bytes (i.e. the Endian type).
127 // The easiest case is the one of a DICOM header, since it possesses a
128 // file preamble where it suffice to look for the sting "DICM".
129 lgrLue = fread(deb, 1, HEADER_LENGTH_TO_READ, fp);
132 if(memcmp(entCur, "DICM", (size_t)4) == 0) {
133 filetype = TrueDicom;
134 dbg.Verbose(1, "gdcmHeader::CheckSwap:", "looks like DICOM Version3");
137 dbg.Verbose(1, "gdcmHeader::CheckSwap:", "not a DICOM Version3 file");
140 if(filetype == TrueDicom) {
141 // Next, determine the value representation (VR). Let's skip to the
142 // first element (0002, 0000) and check there if we find "UL", in
143 // which case we (almost) know it is explicit VR.
144 // WARNING: if it happens to be implicit VR then what we will read
145 // is the length of the group. If this ascii representation of this
146 // length happens to be "UL" then we shall believe it is explicit VR.
147 // FIXME: in order to fix the above warning, we could read the next
148 // element value (or a couple of elements values) in order to make
149 // sure we are not commiting a big mistake.
151 // * the 128 bytes of File Preamble (often padded with zeroes),
152 // * the 4 bytes of "DICM" string,
153 // * the 4 bytes of the first tag (0002, 0000),
154 // i.e. a total of 136 bytes.
156 if(memcmp(entCur, "UL", (size_t)2) == 0) {
157 filetype = ExplicitVR;
158 dbg.Verbose(1, "gdcmHeader::CheckSwap:",
159 "explicit Value Representation");
161 filetype = ImplicitVR;
162 dbg.Verbose(1, "gdcmHeader::CheckSwap:",
163 "not an explicit Value Representation");
168 dbg.Verbose(1, "gdcmHeader::CheckSwap:",
169 "HostByteOrder != NetworkByteOrder");
172 dbg.Verbose(1, "gdcmHeader::CheckSwap:",
173 "HostByteOrder = NetworkByteOrder");
176 // Position the file position indicator at first tag (i.e.
177 // after the file preamble and the "DICM" string).
179 fseek (fp, 132L, SEEK_SET);
181 } // End of TrueDicom
183 // Alas, this is not a DicomV3 file and whatever happens there is no file
184 // preamble. We can reset the file position indicator to where the data
185 // is (i.e. the beginning of the file).
188 // Our next best chance would be to be considering a 'clean' ACR/NEMA file.
189 // By clean we mean that the length of the first tag is written down.
190 // If this is the case and since the length of the first group HAS to be
191 // four (bytes), then determining the proper swap code is straightforward.
194 s = str2num(entCur, guint32);
214 dbg.Verbose(0, "gdcmHeader::CheckSwap:",
215 "ACR/NEMA unfound swap info (time to raise bets)");
218 // We are out of luck. It is not a DicomV3 nor a 'clean' ACR/NEMA file.
219 // It is time for despaired wild guesses. So, let's assume this file
220 // happens to be 'dirty' ACR/NEMA, i.e. the length of the group is
221 // not present. Then the only info we have is the net2host one.
229 void gdcmHeader::SwitchSwapToBigEndian(void) {
230 dbg.Verbose(1, "gdcmHeader::SwitchSwapToBigEndian",
231 "Switching to BigEndian mode.");
248 void gdcmHeader::GetPixels(size_t lgrTotale, void* _Pixels) {
250 pixelsOffset = GetPixelOffset();
251 printf("pixelsOffset %d\n",pixelsOffset);
252 fseek(fp, pixelsOffset, SEEK_SET);
253 fread(_Pixels, 1, lgrTotale, fp);
259 * \ingroup gdcmHeader
260 * \brief Find the value representation of the current tag.
262 * @param sw code swap
263 * @param skippedLength pointeur sur nombre d'octets que l'on a saute qd
264 * la lecture est finie
265 * @param longueurLue pointeur sur longueur (en nombre d'octets)
267 * @return longueur retenue pour le champ
272 // --> C'etait la description de quoi, ca?
275 void gdcmHeader::FindVR( ElValue *ElVal) {
276 if (filetype != ExplicitVR)
282 long PositionOnEntry = ftell(fp);
283 // Warning: we believe this is explicit VR (Value Representation) because
284 // we used a heuristic that found "UL" in the first tag. Alas this
285 // doesn't guarantee that all the tags will be in explicit VR. In some
286 // cases (see e-film filtered files) one finds implicit VR tags mixed
287 // within an explicit VR file. Hence we make sure the present tag
288 // is in explicit VR and try to fix things if it happens not to be
290 bool RealExplicit = true;
292 lgrLue=fread (&VR, (size_t)2,(size_t)1, fp);
296 // Assume we are reading a falsely explicit VR file i.e. we reached
297 // a tag where we expect reading a VR but are in fact we read the
298 // first to bytes of the length. Then we will interogate (through find)
299 // the dicom_vr dictionary with oddities like "\004\0" which crashes
300 // both GCC and VC++ implementations of the STL map. Hence when the
301 // expected VR read happens to be non-ascii characters we consider
302 // we hit falsely explicit VR tag.
304 if ( (!isalpha(VR[0])) && (!isalpha(VR[1])) )
305 RealExplicit = false;
307 // CLEANME searching the dicom_vr at each occurence is expensive.
308 // PostPone this test in an optional integrity check at the end
309 // of parsing or only in debug mode.
310 if ( RealExplicit && !dicom_vr->count(vr) )
311 RealExplicit = false;
313 if ( RealExplicit ) {
314 if ( ElVal->IsVrUnknown() ) {
315 // When not a dictionary entry, we can safely overwrite the vr.
319 if ( ElVal->GetVR() == vr ) {
320 // The vr we just read and the dictionary agree. Nothing to do.
323 // The vr present in the file and the dictionary disagree. We assume
324 // the file writer knew best and use the vr of the file. Since it would
325 // be unwise to overwrite the vr of a dictionary (since it would
326 // compromise it's next user), we need to clone the actual DictEntry
327 // and change the vr for the read one.
328 gdcmDictEntry* NewTag = new gdcmDictEntry(ElVal->GetGroup(),
333 ElVal->SetDictEntry(NewTag);
337 // We thought this was explicit VR, but we end up with an
338 // implicit VR tag. Let's backtrack.
339 dbg.Verbose(1, "gdcmHeader::FindVR:", "Falsely explicit vr file");
340 fseek(fp, PositionOnEntry, SEEK_SET);
341 // When this element is known in the dictionary we shall use, e.g. for
342 // the semantics (see the usage of IsAnInteger), the vr proposed by the
343 // dictionary entry. Still we have to flag the element as implicit since
344 // we know now our assumption on expliciteness is not furfilled.
346 if ( ElVal->IsVrUnknown() )
347 ElVal->SetVR("Implicit");
348 ElVal->SetImplicitVr();
352 * \ingroup gdcmHeader
353 * \brief Determines if the Transfer Syntax was allready encountered
354 * and if it corresponds to a ImplicitVRLittleEndian one.
356 * @return True when ImplicitVRLittleEndian found. False in all other cases.
358 bool gdcmHeader::IsImplicitVRLittleEndianTransferSyntax(void) {
359 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
362 LoadElementValueSafe(Element);
363 string Transfer = Element->GetValue();
364 if ( Transfer == "1.2.840.10008.1.2" )
370 * \ingroup gdcmHeader
371 * \brief Determines if the Transfer Syntax was allready encountered
372 * and if it corresponds to a ExplicitVRLittleEndian one.
374 * @return True when ExplicitVRLittleEndian found. False in all other cases.
376 bool gdcmHeader::IsExplicitVRLittleEndianTransferSyntax(void) {
377 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
380 LoadElementValueSafe(Element);
381 string Transfer = Element->GetValue();
382 if ( Transfer == "1.2.840.10008.1.2.1" )
388 * \ingroup gdcmHeader
389 * \brief Determines if the Transfer Syntax was allready encountered
390 * and if it corresponds to a DeflatedExplicitVRLittleEndian one.
392 * @return True when DeflatedExplicitVRLittleEndian found. False in all other cases.
394 bool gdcmHeader::IsDeflatedExplicitVRLittleEndianTransferSyntax(void) {
395 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
398 LoadElementValueSafe(Element);
399 string Transfer = Element->GetValue();
400 if ( Transfer == "1.2.840.10008.1.2.1.99" )
407 * \ingroup gdcmHeader
408 * \brief Determines if the Transfer Syntax was allready encountered
409 * and if it corresponds to a Explicit VR Big Endian one.
411 * @return True when big endian found. False in all other cases.
413 bool gdcmHeader::IsExplicitVRBigEndianTransferSyntax(void) {
414 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
417 LoadElementValueSafe(Element);
418 string Transfer = Element->GetValue();
419 if ( Transfer == "1.2.840.10008.1.2.2" )
426 * \ingroup gdcmHeader
427 * \brief Determines if the Transfer Syntax was allready encountered
428 * and if it corresponds to a JPEGBaseLineProcess1 one.
430 * @return True when JPEGBaseLineProcess1found. False in all other cases.
432 bool gdcmHeader::IsJPEGBaseLineProcess1TransferSyntax(void) {
433 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
436 LoadElementValueSafe(Element);
437 string Transfer = Element->GetValue();
438 if ( Transfer == "1.2.840.10008.1.2.4.50" )
444 * \ingroup gdcmHeader
445 * \brief Determines if the Transfer Syntax was allready encountered
446 * and if it corresponds to a JPEGExtendedProcess2-4 one.
448 * @return True when JPEGExtendedProcess2-4 found. False in all other cases.
450 bool gdcmHeader::IsJPEGExtendedProcess2_4TransferSyntax(void) {
451 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
454 LoadElementValueSafe(Element);
455 string Transfer = Element->GetValue();
456 if ( Transfer == "1.2.840.10008.1.2.4.51" )
463 * \ingroup gdcmHeader
464 * \brief Determines if the Transfer Syntax was allready encountered
465 * and if it corresponds to a JPEGExtendeProcess3-5 one.
467 * @return True when JPEGExtendedProcess3-5 found. False in all other cases.
469 bool gdcmHeader::IsJPEGExtendedProcess3_5TransferSyntax(void) {
470 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
473 LoadElementValueSafe(Element);
474 string Transfer = Element->GetValue();
475 if ( Transfer == "1.2.840.10008.1.2.4.52" )
481 * \ingroup gdcmHeader
482 * \brief Determines if the Transfer Syntax was allready encountered
483 * and if it corresponds to a JPEGSpectralSelectionProcess6-8 one.
485 * @return True when JPEGSpectralSelectionProcess6-8 found. False in all other cases.
487 bool gdcmHeader::IsJPEGSpectralSelectionProcess6_8TransferSyntax(void) {
488 ElValue* Element = PubElVals.GetElementByNumber(0x0002, 0x0010);
491 LoadElementValueSafe(Element);
492 string Transfer = Element->GetValue();
493 if ( Transfer == "1.2.840.10008.1.2.4.53" )
500 // Il y en a encore DIX-SEPT, comme ça.
501 // Il faudrait trouver qq chose + rusé ...
505 void gdcmHeader::FixFoundLength(ElValue * ElVal, guint32 FoundLength) {
506 // Heuristic: a final fix.
507 if ( FoundLength == 0xffffffff)
509 ElVal->SetLength(FoundLength);
512 guint32 gdcmHeader::FindLengthOB(void) {
513 // See PS 3.5-2001, section A.4 p. 49 on encapsulation of encoded pixel data.
516 long PositionOnEntry = ftell(fp);
517 bool FoundSequenceDelimiter = false;
518 guint32 TotalLength = 0;
521 while ( ! FoundSequenceDelimiter) {
524 TotalLength += 4; // We even have to decount the group and element
526 dbg.Verbose(1, "gdcmHeader::FindLengthOB: ",
527 "wrong group for an item sequence.");
528 throw Error::FileReadError(fp, "gdcmHeader::FindLengthOB");
531 FoundSequenceDelimiter = true;
532 else if ( n != 0xe000) {
533 dbg.Verbose(1, "gdcmHeader::FindLengthOB: ",
534 "wrong element for an item sequence.");
535 throw Error::FileReadError(fp, "gdcmHeader::FindLengthOB");
537 ItemLength = ReadInt32();
538 TotalLength += ItemLength + 4; // We add 4 bytes since we just read
539 // the ItemLength with ReadInt32
540 SkipBytes(ItemLength);
542 fseek(fp, PositionOnEntry, SEEK_SET);
546 void gdcmHeader::FindLength(ElValue * ElVal) {
547 guint16 element = ElVal->GetElement();
548 string vr = ElVal->GetVR();
551 if ( (filetype == ExplicitVR) && ! ElVal->IsImplicitVr() ) {
553 if ( (vr=="OB") || (vr=="OW") || (vr=="SQ") || (vr=="UN") ) {
554 // The following reserved two bytes (see PS 3.5-2001, section
555 // 7.1.2 Data element structure with explicit vr p27) must be
556 // skipped before proceeding on reading the length on 4 bytes.
557 fseek(fp, 2L, SEEK_CUR);
558 guint32 length32 = ReadInt32();
559 if ( (vr == "OB") && (length32 == 0xffffffff) ) {
560 ElVal->SetLength(FindLengthOB());
563 FixFoundLength(ElVal, length32);
567 // Length is encoded on 2 bytes.
568 length16 = ReadInt16();
570 // We can tell the current file is encoded in big endian (like
571 // Data/US-RGB-8-epicard) when we find the "Transfer Syntax" tag
572 // and it's value is the one of the encoding of a big endian file.
573 // In order to deal with such big endian encoded files, we have
574 // (at least) two strategies:
575 // * when we load the "Transfer Syntax" tag with value of big endian
576 // encoding, we raise the proper flags. Then we wait for the end
577 // of the META group (0x0002) among which is "Transfer Syntax",
578 // before switching the swap code to big endian. We have to postpone
579 // the switching of the swap code since the META group is fully encoded
580 // in little endian, and big endian coding only starts at the next
581 // group. The corresponding code can be hard to analyse and adds
582 // many additional unnecessary tests for regular tags.
583 // * the second strategy consists in waiting for trouble, that shall appear
584 // when we find the first group with big endian encoding. This is
585 // easy to detect since the length of a "Group Length" tag (the
586 // ones with zero as element number) has to be of 4 (0x0004). When we
587 // encouter 1024 (0x0400) chances are the encoding changed and we
588 // found a group with big endian encoding.
589 // We shall use this second strategy. In order make sure that we
590 // can interpret the presence of an apparently big endian encoded
591 // length of a "Group Length" without committing a big mistake, we
592 // add an additional check: we look in the allready parsed elements
593 // for the presence of a "Transfer Syntax" whose value has to be "big
594 // endian encoding". When this is the case, chances are we got our
595 // hands on a big endian encoded file: we switch the swap code to
596 // big endian and proceed...
597 if ( (element == 0x000) && (length16 == 0x0400) ) {
598 if ( ! IsExplicitVRBigEndianTransferSyntax() )
599 throw Error::FileReadError(fp, "gdcmHeader::FindLength");
601 SwitchSwapToBigEndian();
602 // Restore the unproperly loaded values i.e. the group, the element
603 // and the dictionary entry depending on them.
604 guint16 CorrectGroup = SwapShort(ElVal->GetGroup());
605 guint16 CorrectElem = SwapShort(ElVal->GetElement());
606 gdcmDictEntry * NewTag = IsInDicts(CorrectGroup, CorrectElem);
608 // This correct tag is not in the dictionary. Create a new one.
609 NewTag = new gdcmDictEntry(CorrectGroup, CorrectElem);
611 // FIXME this can create a memory leaks on the old entry that be
612 // left unreferenced.
613 ElVal->SetDictEntry(NewTag);
616 // Heuristic: well some files are really ill-formed.
617 if ( length16 == 0xffff) {
619 dbg.Verbose(0, "gdcmHeader::FindLength",
620 "Erroneous element length fixed.");
622 FixFoundLength(ElVal, (guint32)length16);
626 // Either implicit VR or a non DICOM conformal (see not below) explicit
627 // VR that ommited the VR of (at least) this element. Farts happen.
628 // [Note: according to the part 5, PS 3.5-2001, section 7.1 p25
629 // on Data elements "Implicit and Explicit VR Data Elements shall
630 // not coexist in a Data Set and Data Sets nested within it".]
631 // Length is on 4 bytes.
632 FixFoundLength(ElVal, ReadInt32());
636 * \ingroup gdcmHeader
637 * \brief Swaps back the bytes of 4-byte long integer accordingly to
640 * @return The suggested integer.
642 guint32 gdcmHeader::SwapLong(guint32 a) {
643 // FIXME: il pourrait y avoir un pb pour les entiers negatifs ...
648 a=( ((a<<24) & 0xff000000) | ((a<<8) & 0x00ff0000) |
649 ((a>>8) & 0x0000ff00) | ((a>>24) & 0x000000ff) );
653 a=( ((a<<16) & 0xffff0000) | ((a>>16) & 0x0000ffff) );
657 a=( ((a<<8) & 0xff00ff00) | ((a>>8) & 0x00ff00ff) );
660 dbg.Error(" gdcmHeader::SwapLong : unset swap code");
667 * \ingroup gdcmHeader
668 * \brief Swaps the bytes so they agree with the processor order
669 * @return The properly swaped 16 bits integer.
671 guint16 gdcmHeader::SwapShort(guint16 a) {
672 if ( (sw==4321) || (sw==2143) )
673 a =(((a<<8) & 0x0ff00) | ((a>>8)&0x00ff));
677 void gdcmHeader::SkipBytes(guint32 NBytes) {
678 //FIXME don't dump the returned value
679 (void)fseek(fp, (long)NBytes, SEEK_CUR);
682 void gdcmHeader::SkipElementValue(ElValue * ElVal) {
683 SkipBytes(ElVal->GetLength());
686 void gdcmHeader::SetMaxSizeLoadElementValue(long NewSize) {
689 if ((guint32)NewSize >= (guint32)0xffffffff) {
690 MaxSizeLoadElementValue = 0xffffffff;
693 MaxSizeLoadElementValue = NewSize;
697 * \ingroup gdcmHeader
698 * \brief Loads the element if it's size is not to big.
699 * @param ElVal Element whose value shall be loaded.
700 * @param MaxSize Size treshold above which the element value is not
701 * loaded in memory. The element value is allways loaded
702 * when MaxSize is equal to UINT32_MAX.
705 void gdcmHeader::LoadElementValue(ElValue * ElVal) {
707 guint16 group = ElVal->GetGroup();
708 guint16 elem = ElVal->GetElement();
709 string vr = ElVal->GetVR();
710 guint32 length = ElVal->GetLength();
711 bool SkipLoad = false;
713 fseek(fp, (long)ElVal->GetOffset(), SEEK_SET);
715 // Sequences not treated yet !
717 // Ne faudrait-il pas au contraire trouver immediatement
718 // une maniere 'propre' de traiter les sequences (vr = SQ)
719 // car commencer par les ignorer risque de conduire a qq chose
720 // qui pourrait ne pas etre generalisable
725 // Heuristic : a sequence "contains" a set of tags (called items). It looks
726 // like the last tag of a sequence (the one that terminates the sequence)
727 // has a group of 0xfffe (with a dummy length).
728 if( group == 0xfffe )
731 // The group length doesn't represent data to be loaded in memory, since
732 // each element of the group shall be loaded individualy.
737 // FIXME the following skip is not necessary
738 SkipElementValue(ElVal);
740 ElVal->SetValue("gdcm::Skipped");
744 // When the length is zero things are easy:
750 // Values bigger than specified are not loaded.
752 // En fait, c'est les elements dont la longueur est superieure
753 // a celle fixee qui ne sont pas charges
755 if (length > MaxSizeLoadElementValue) {
757 s << "gdcm::NotLoaded.";
758 s << " Address:" << (long)ElVal->GetOffset();
759 s << " Length:" << ElVal->GetLength();
760 //mesg += " Length:" + ElVal->GetLength();
761 ElVal->SetValue(s.str());
765 // When an integer is expected, read and convert the following two or
766 // four bytes properly i.e. as an integer as opposed to a string.
767 if ( IsAnInteger(ElVal) ) {
770 NewInt = ReadInt16();
771 } else if( length == 4 ) {
772 NewInt = ReadInt32();
774 dbg.Error(true, "LoadElementValue: Inconsistency when reading Int.");
776 //FIXME: make the following an util fonction
779 ElVal->SetValue(s.str());
783 // FIXME The exact size should be length if we move to strings or whatever
786 // QUESTION : y a-t-il une raison pour ne pas utiliser g_malloc ici ?
789 char* NewValue = (char*)malloc(length+1);
791 dbg.Verbose(1, "LoadElementValue: Failed to allocate NewValue");
796 item_read = fread(NewValue, (size_t)length, (size_t)1, fp);
797 if ( item_read != 1 ) {
799 Error::FileReadError(fp, "gdcmHeader::LoadElementValue");
800 ElVal->SetValue("gdcm::UnRead");
803 ElVal->SetValue(NewValue);
807 * \ingroup gdcmHeader
808 * \brief Loads the element while preserving the current
809 * underlying file position indicator as opposed to
810 * to LoadElementValue that modifies it.
811 * @param ElVal Element whose value shall be loaded.
814 void gdcmHeader::LoadElementValueSafe(ElValue * ElVal) {
815 long PositionOnEntry = ftell(fp);
816 LoadElementValue(ElVal);
817 fseek(fp, PositionOnEntry, SEEK_SET);
821 guint16 gdcmHeader::ReadInt16(void) {
824 item_read = fread (&g, (size_t)2,(size_t)1, fp);
825 if ( item_read != 1 )
826 throw Error::FileReadError(fp, "gdcmHeader::ReadInt16");
831 guint32 gdcmHeader::ReadInt32(void) {
834 item_read = fread (&g, (size_t)4,(size_t)1, fp);
835 if ( item_read != 1 )
836 throw Error::FileReadError(fp, "gdcmHeader::ReadInt32");
842 * \ingroup gdcmHeader
843 * \brief Read the next tag without loading it's value
844 * @return On succes the newly created ElValue, NULL on failure.
847 ElValue * gdcmHeader::ReadNextElement(void) {
856 catch ( Error::FileReadError ) {
857 // We reached the EOF (or an error occured) and header parsing
858 // has to be considered as finished.
862 // Find out if the tag we encountered is in the dictionaries:
863 gdcmDictEntry * NewTag = IsInDicts(g, n);
865 NewTag = new gdcmDictEntry(g, n);
867 NewElVal = new ElValue(NewTag);
869 dbg.Verbose(1, "ReadNextElement: failed to allocate ElValue");
874 try { FindLength(NewElVal); }
875 catch ( Error::FileReadError ) { // Call it quits
878 NewElVal->SetOffset(ftell(fp));
882 bool gdcmHeader::IsAnInteger(ElValue * ElVal) {
883 guint16 group = ElVal->GetGroup();
884 guint16 element = ElVal->GetElement();
885 string vr = ElVal->GetVR();
886 guint32 length = ElVal->GetLength();
888 // When we have some semantics on the element we just read, and if we
889 // a priori know we are dealing with an integer, then we shall be
890 // able to swap it's element value properly.
891 if ( element == 0 ) { // This is the group length of the group
895 dbg.Error("gdcmHeader::IsAnInteger",
896 "Erroneous Group Length element length.");
899 if ( group % 2 != 0 )
900 // We only have some semantics on documented elements, which are
904 if ( (length != 4) && ( length != 2) )
905 // Swapping only make sense on integers which are 2 or 4 bytes long.
908 if ( (vr == "UL") || (vr == "US") || (vr == "SL") || (vr == "SS") )
911 if ( (group == 0x0028) && (element == 0x0005) )
912 // This tag is retained from ACR/NEMA
913 // CHECKME Why should "Image Dimensions" be a single integer ?
915 // "Image Dimensions", c'est en fait le 'nombre de dimensions'
916 // de l'objet ACR-NEMA stocké
922 // DICOM V3 ne retient pas cette information
923 // Par defaut, tout est 'Image',
924 // C'est a l'utilisateur d'explorer l'ensemble des entetes
925 // pour savoir à quoi il a a faire
927 // Le Dicom Multiframe peut etre utilise pour stocker,
928 // dans un seul fichier, une serie temporelle (cardio vasculaire GE, p.ex)
929 // ou un volume (medecine Nucleaire, p.ex)
933 if ( (group == 0x0028) && (element == 0x0200) )
934 // This tag is retained from ACR/NEMA
941 * \ingroup gdcmHeader
942 * \brief Recover the offset (from the beginning of the file) of the pixels.
944 size_t gdcmHeader::GetPixelOffset(void) {
945 // If this file complies with the norm we should encounter the
946 // "Image Location" tag (0x0028, 0x0200). This tag contains the
947 // the group that contains the pixel data (hence the "Pixel Data"
948 // is found by indirection through the "Image Location").
949 // Inside the group pointed by "Image Location" the searched element
950 // is conventionally the element 0x0010 (when the norm is respected).
951 // When the "Image Location" is absent we default to group 0x7fe0.
954 string ImageLocation = GetPubElValByName("Image Location");
955 if ( ImageLocation == "gdcm::Unfound" ) {
958 grPixel = (guint16) atoi( ImageLocation.c_str() );
960 if (grPixel != 0x7fe0)
961 // FIXME is this still necessary ?
962 // Now, this looks like an old dirty fix for Philips imager
966 ElValue* PixelElement = PubElVals.GetElementByNumber(grPixel, numPixel);
968 return PixelElement->GetOffset();
973 gdcmDictEntry * gdcmHeader::IsInDicts(guint32 group, guint32 element) {
975 // Y a-t-il une raison de lui passer des guint32
976 // alors que group et element sont des guint16?
978 gdcmDictEntry * found = (gdcmDictEntry*)0;
979 if (!RefPubDict && !RefShaDict) {
980 //FIXME build a default dictionary !
981 printf("FIXME in gdcmHeader::IsInDicts\n");
984 found = RefPubDict->GetTag(group, element);
989 found = RefShaDict->GetTag(group, element);
996 list<string> * gdcmHeader::GetPubTagNames(void) {
997 list<string> * Result = new list<string>;
998 TagHT entries = RefPubDict->GetEntries();
1000 for (TagHT::iterator tag = entries.begin(); tag != entries.end(); ++tag){
1001 Result->push_back( tag->second->GetName() );
1006 map<string, list<string> > * gdcmHeader::GetPubTagNamesByCategory(void) {
1007 map<string, list<string> > * Result = new map<string, list<string> >;
1008 TagHT entries = RefPubDict->GetEntries();
1010 for (TagHT::iterator tag = entries.begin(); tag != entries.end(); ++tag){
1011 (*Result)[tag->second->GetFourth()].push_back(tag->second->GetName());
1016 string gdcmHeader::GetPubElValByNumber(guint16 group, guint16 element) {
1017 return PubElVals.GetElValueByNumber(group, element);
1020 string gdcmHeader::GetPubElValRepByNumber(guint16 group, guint16 element) {
1021 ElValue* elem = PubElVals.GetElementByNumber(group, element);
1023 return "gdcm::Unfound";
1024 return elem->GetVR();
1027 string gdcmHeader::GetPubElValByName(string TagName) {
1028 return PubElVals.GetElValueByName(TagName);
1031 string gdcmHeader::GetPubElValRepByName(string TagName) {
1032 ElValue* elem = PubElVals.GetElementByName(TagName);
1034 return "gdcm::Unfound";
1035 return elem->GetVR();
1038 string gdcmHeader::GetShaElValByNumber(guint16 group, guint16 element) {
1039 return ShaElVals.GetElValueByNumber(group, element);
1042 string gdcmHeader::GetShaElValRepByNumber(guint16 group, guint16 element) {
1043 ElValue* elem = ShaElVals.GetElementByNumber(group, element);
1045 return "gdcm::Unfound";
1046 return elem->GetVR();
1049 string gdcmHeader::GetShaElValByName(string TagName) {
1050 return ShaElVals.GetElValueByName(TagName);
1053 string gdcmHeader::GetShaElValRepByName(string TagName) {
1054 ElValue* elem = ShaElVals.GetElementByName(TagName);
1056 return "gdcm::Unfound";
1057 return elem->GetVR();
1061 string gdcmHeader::GetElValByNumber(guint16 group, guint16 element) {
1062 string pub = GetPubElValByNumber(group, element);
1065 return GetShaElValByNumber(group, element);
1068 string gdcmHeader::GetElValRepByNumber(guint16 group, guint16 element) {
1069 string pub = GetPubElValRepByNumber(group, element);
1072 return GetShaElValRepByNumber(group, element);
1075 string gdcmHeader::GetElValByName(string TagName) {
1076 string pub = GetPubElValByName(TagName);
1079 return GetShaElValByName(TagName);
1082 string gdcmHeader::GetElValRepByName(string TagName) {
1083 string pub = GetPubElValRepByName(TagName);
1086 return GetShaElValRepByName(TagName);
1090 * \ingroup gdcmHeader
1091 * \brief Modifie la valeur d'un ElValue déja existant
1092 * \ dans le PubElVals du gdcmHeader,
1093 * \ accédé par ses numero de groupe et d'element.
1095 int gdcmHeader::SetPubElValByNumber(string content, guint16 group, guint16 element) {
1096 //TagKey key = gdcmDictEntry::TranslateToKey(group, element);
1097 //PubElVals.tagHt[key]->SetValue(content);
1099 return ( PubElVals.SetElValueByNumber (content, group, element) );
1104 * \ingroup gdcmHeader
1105 * \brief Modifie la valeur d'un ElValue déja existant
1106 * \ dans le PubElVals du gdcmHeader,
1107 * \ accédé par son nom
1109 int gdcmHeader::SetPubElValByName(string content, string TagName) {
1110 //TagKey key = gdcmDictEntry::TranslateToKey(group, element);
1111 //PubElVals.tagHt[key]->SetValue(content);
1113 return ( PubElVals.SetElValueByName (content, TagName) );
1118 * \ingroup gdcmHeader
1119 * \brief Modifie la valeur d'un ElValue déja existant
1120 * \ dans le ShaElVals du gdcmHeader,
1121 * \ accédé par ses numero de groupe et d'element.
1123 int gdcmHeader::SetShaElValByNumber(string content, guint16 group, guint16 element) {
1125 return ( ShaElVals.SetElValueByNumber (content, group, element) );
1130 * \ingroup gdcmHeader
1131 * \brief Modifie la valeur d'un ElValue déja existant
1132 * \ dans le ShaElVals du gdcmHeader,
1133 * \ accédé par son nom
1135 int gdcmHeader::SetShaElValByName(string content, string TagName) {
1137 return ( ShaElVals.SetElValueByName (content, TagName) );
1140 * \ingroup gdcmHeader
1141 * \brief Parses the header of the file but does NOT load element values.
1143 void gdcmHeader::ParseHeader(void) {
1144 ElValue * newElValue = (ElValue *)0;
1148 while ( (newElValue = ReadNextElement()) ) {
1149 SkipElementValue(newElValue);
1150 PubElVals.Add(newElValue);
1155 * \ingroup gdcmHeader
1156 * \brief Loads the element values of all the elements present in the
1157 * public tag based hash table.
1159 void gdcmHeader::LoadElements(void) {
1161 if (DEBUG) printf("LoadElements : Entree\n");
1164 if (DEBUG) printf("LoadElements : rewind\n");
1166 TagElValueHT ht = PubElVals.GetTagHt();
1168 if (DEBUG) printf("LoadElements : GetTagHt\n");
1170 for (TagElValueHT::iterator tag = ht.begin(); tag != ht.end(); ++tag) {
1171 LoadElementValue(tag->second);
1175 void gdcmHeader::PrintPubElVal(ostream & os) {
1176 PubElVals.Print(os);
1179 void gdcmHeader::PrintPubDict(ostream & os) {
1180 RefPubDict->Print(os);