DYT/Tool/3rdParty_x64/include/dcmtk/dcmdata/dcsequen.h
2024-11-22 23:19:31 +08:00

607 lines
31 KiB
C++

/*
*
* Copyright (C) 1994-2015, OFFIS e.V.
* All rights reserved. See COPYRIGHT file for details.
*
* This software and supporting documentation were developed by
*
* OFFIS e.V.
* R&D Division Health
* Escherweg 2
* D-26121 Oldenburg, Germany
*
*
* Module: dcmdata
*
* Author: Gerd Ehlers, Andreas Barth
*
* Purpose: Interface of class DcmSequenceOfItems
*
*/
#ifndef DCSEQUEN_H
#define DCSEQUEN_H
#include "dcmtk/config/osconfig.h" /* make sure OS specific configuration is included first */
#include "dcmtk/ofstd/offile.h" /* for offile_off_t */
#include "dcmtk/dcmdata/dcelem.h"
#include "dcmtk/dcmdata/dctag.h"
#include "dcmtk/dcmdata/dclist.h"
#include "dcmtk/dcmdata/dcstack.h"
/** class representing a DICOM Sequence of Items (SQ).
* This class is derived from class DcmElement (and not from DcmObject) despite the fact
* that sequences have no value field as such, they maintain a list of items. However,
* all APIs in class DcmItem and class DcmDataset accept DcmElements.
* This is ugly and causes some DcmElement API methods to be useless with DcmSequence.
*/
class DCMTK_DCMDATA_EXPORT DcmSequenceOfItems : public DcmElement
{
public:
/** constructor
* @param tag attribute tag
* @param len length of the attribute value
* @param readAsUN flag indicating whether the sequence should be
* read (interpreted) as a UN element with Implicit VR Little Endian encoding
*/
DcmSequenceOfItems(const DcmTag &tag,
const Uint32 len = 0,
OFBool readAsUN = OFFalse);
/** copy constructor
* @param oldSeq element to be copied
*/
DcmSequenceOfItems(const DcmSequenceOfItems& oldSeq);
/// destructor
virtual ~DcmSequenceOfItems();
/** copy assignment operator
* @param obj element to be copied
*/
DcmSequenceOfItems &operator=(const DcmSequenceOfItems &obj);
/** comparison operator that compares the normalized value of this object
* with a given object of the same type. The tag of the element is also
* considered as the first component that is compared, followed by the
* object types (VR, i.e. DCMTK'S EVR) and the comparison of all value
* components of the object, preferably in the order declared in the
* object (if applicable). For sequences that means that all
* contained items are compared element by element, so this may be
* an expensive operation!
* @param rhs the right hand side of the comparison
* @return 0 if the object values are equal.
* -1 if either the value of the first component that does not match
* is lower in this object than in rhs, or all compared components match
* but this object has fewer components than rhs. Also returned if rhs
* cannot be casted to this object type.
* 1 if either the value of the first component that does not match
* is greater in this object than in rhs object, or all compared
* components match but the this component is longer.
*/
virtual int compare(const DcmElement& rhs) const;
/// returns current status flag
inline OFCondition error() const { return errorFlag; }
/** clone method
* @return deep copy of this object
*/
virtual DcmObject *clone() const
{
return new DcmSequenceOfItems(*this);
}
/** Virtual object copying. This method can be used for DcmObject
* and derived classes to get a deep copy of an object. Internally
* the assignment operator is called if the given DcmObject parameter
* is of the same type as "this" object instance. If not, an error
* is returned. This function permits copying an object by value
* in a virtual way which therefore is different to just calling the
* assignment operator of DcmElement which could result in slicing
* the object.
* @param rhs - [in] The instance to copy from. Has to be of the same
* class type as "this" object
* @return EC_Normal if copying was successful, error otherwise
*/
virtual OFCondition copyFrom(const DcmObject& rhs);
/** return identifier for this class. Every class derived from this class
* returns a unique value of type enum DcmEVR for this call. This is used
* as a "poor man's RTTI" to correctly identify instances derived from
* this class even on compilers not supporting RTTI.
* @return type identifier of this class
*/
virtual DcmEVR ident() const { return EVR_SQ; }
/** check if this element is a leaf node in a dataset tree.
* All subclasses of DcmElement except for DcmSequenceOfItems
* are leaf nodes, while DcmSequenceOfItems, DcmItem, DcmDataset etc.
* are not.
* @return true if leaf node, false otherwise.
*/
virtual OFBool isLeaf() const { return OFFalse; }
/** print object to a stream
* @param out output stream
* @param flags optional flag used to customize the output (see DCMTypes::PF_xxx)
* @param level current level of nested items. Used for indentation.
* @param pixelFileName not used (used in certain sub-classes of this class)
* @param pixelCounter not used (used in certain sub-classes of this class)
*/
virtual void print(STD_NAMESPACE ostream&out,
const size_t flags = 0,
const int level = 0,
const char *pixelFileName = NULL,
size_t *pixelCounter = NULL);
/** check whether stored value conforms to the VR and to the specified VM
* @param card cardinality (number of items) to be checked for.
* (See DcmElement::checkVM() for a list of valid values.)
* Parameter used to specify the value multiplicity for non-sequence attributes.
* @param oldFormat parameter not used for this VR (only for DA, TM)
* @return status of the check, EC_Normal if value is correct, an error code otherwise
*/
virtual OFCondition checkValue(const OFString &card = "1-n",
const OFBool oldFormat = OFFalse);
/** get value multiplicity
* @return always returns 1 (according to the DICOM standard)
*/
virtual unsigned long getVM() { return 1L; }
/** This function takes care of group length and padding elements
* in the current element list according to what is specified in
* glenc and padenc. If required, this function does the following
* two things:
* a) it calculates the group length of all groups which are
* contained in this item and sets the calculated values
* in the corresponding group length elements and
* b) it inserts a corresponding padding element (or, in case
* of sequences: padding elements) with a corresponding correct
* size into the element list.
* @param glenc Encoding type for group length; specifies what shall
* be done with group length tags.
* @param padenc Encoding type for padding; specifies what shall be
* done with padding tags.
* @param xfer The transfer syntax that shall be used.
* @param enctype Encoding type for sequences; specifies how sequences
* will be handled.
* @param padlen The length up to which the dataset shall be padded,
* if padding is desired.
* @param subPadlen For sequences (ie sub elements), the length up to
* which item shall be padded, if padding is desired.
* @param instanceLength Number of extra bytes added to the item/dataset
* length used when computing the padding; this
* parameter is for instance used to pass the length
* of the file meta header from the DcmFileFormat to
* the DcmDataset object.
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition computeGroupLengthAndPadding
(const E_GrpLenEncoding glenc,
const E_PaddingEncoding padenc = EPD_noChange,
const E_TransferSyntax xfer = EXS_Unknown,
const E_EncodingType enctype = EET_ExplicitLength,
const Uint32 padlen = 0,
const Uint32 subPadlen = 0,
Uint32 instanceLength = 0);
/** calculate the length of this DICOM element when encoded with the
* given transfer syntax and the given encoding type for sequences.
* For elements, the length includes the length of the tag, length field,
* VR field and the value itself, for items and sequences it returns
* the length of the complete item or sequence including delimitation tags
* if applicable.
* If length encoding is set to be explicit and the total sequence size is
* larger than the available 32-bit length field, then undefined length
* is returned. If "dcmWriteOversizedSeqsAndItemsUndefined" is disabled,
* also the internal DcmObject errorFlag is set to EC_SeqOrItemContentOverflow
* in case the sequence content (excluding tag header etc.) is already too
* large.
* @param xfer transfer syntax for length calculation
* @param enctype sequence encoding type for length calculation
* @return length of DICOM element
*/
virtual Uint32 calcElementLength(const E_TransferSyntax xfer,
const E_EncodingType enctype);
/** calculate the value length (without attribute tag, VR and length field)
* of this DICOM element when encoded with the given transfer syntax and
* the given encoding type for sequences.
* If length encoding is set to be explicit and the total sequence size is
* larger than the available 32-bit length field, then undefined length
* is returned. If "dcmWriteOversizedSeqsAndItemsImplicit" is disabled,
* also the internal DcmObject errorFlag is set to
* EC_SeqOrItemContentOverflow.
* @param xfer transfer syntax for length calculation
* @param enctype sequence encoding type for length calculation
* @return value length of DICOM element
*/
virtual Uint32 getLength(const E_TransferSyntax xfer = EXS_LittleEndianImplicit,
const E_EncodingType enctype = EET_UndefinedLength);
/** initialize the transfer state of this object. This method must be called
* before this object is written to a stream or read (parsed) from a stream.
*/
virtual void transferInit();
/** finalize the transfer state of this object. This method must be called
* when reading/writing this object from/to a stream has been completed.
*/
virtual void transferEnd();
/** check if this DICOM object can be encoded in the given transfer syntax.
* @param newXfer transfer syntax in which the DICOM object is to be encoded
* @param oldXfer transfer syntax in which the DICOM object was read or created.
* @return true if object can be encoded in desired transfer syntax, false otherwise.
*/
virtual OFBool canWriteXfer(const E_TransferSyntax oldXfer,
const E_TransferSyntax newXfer);
/** This function reads the information of all attributes which
* are captured in the input stream and captures this information
* in elementList. Each attribute is represented as an element
* in this list. If not all information for an attribute could be
* read from the stream, the function returns EC_StreamNotifyClient.
* @param inStream The stream which contains the information.
* @param xfer The transfer syntax which was used to encode
* the information in inStream.
* @param glenc Encoding type for group length; specifies
* what will be done with group length tags.
* @param maxReadLength Maximum read length for reading an attribute value.
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition read(DcmInputStream &inStream,
const E_TransferSyntax xfer,
const E_GrpLenEncoding glenc = EGL_noChange,
const Uint32 maxReadLength = DCM_MaxReadLength);
/** write object to a stream
* @param outStream DICOM output stream
* @param oxfer output transfer syntax
* @param enctype encoding types (undefined or explicit length)
* @param wcache pointer to write cache object, may be NULL
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition write(DcmOutputStream &outStream,
const E_TransferSyntax oxfer,
const E_EncodingType enctype,
DcmWriteCache *wcache);
/** write object in XML format
* @param out output stream to which the XML document is written
* @param flags optional flag used to customize the output (see DCMTypes::XF_xxx)
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition writeXML(STD_NAMESPACE ostream&out,
const size_t flags = 0);
/** special write method for creation of digital signatures
* @param outStream DICOM output stream
* @param oxfer output transfer syntax
* @param enctype encoding types (undefined or explicit length)
* @param wcache pointer to write cache object, may be NULL
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition writeSignatureFormat(DcmOutputStream &outStream,
const E_TransferSyntax oxfer,
const E_EncodingType enctype,
DcmWriteCache *wcache);
/** returns true if the current object may be included in a digital signature
* @return true if signable, false otherwise
*/
virtual OFBool isSignable() const;
/** returns true if the object contains an element with Unknown VR at any nesting level
* @return true if the object contains an element with Unknown VR, false otherwise
*/
virtual OFBool containsUnknownVR() const;
/** check if this object contains non-ASCII characters at any nesting level. Please note
* that this check is pretty simple and only works for single-byte character sets that
* do include the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other words: All
* character codes below 128 are considered to be ASCII codes and all others are
* considered to be non-ASCII.
* @param checkAllStrings if true, also check elements with string values not affected
* by SpecificCharacterSet (0008,0005). By default, only check PN, LO, LT, SH, ST,
* UC and UT.
* @return true if object contains non-ASCII characters, false otherwise
*/
virtual OFBool containsExtendedCharacters(const OFBool checkAllStrings = OFFalse);
/** check if this object is affected by SpecificCharacterSet at any nesting level.
* In detail, it is checked whether this object contains any data elements that
* according to their VR are affected by the SpecificCharacterSet (0008,0005)
* element. This is true for the following VRs: PN, LO, LT, SH, ST, UC and UT
* @return true if object is affected by SpecificCharacterSet, false otherwise
*/
virtual OFBool isAffectedBySpecificCharacterSet() const;
/** convert all element values that are contained in this item and that are affected
* by SpecificCharacterSet from the currently selected source character set to the
* currently selected destination character set
* @param converter character set converter to be used to convert the element values
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition convertCharacterSet(DcmSpecificCharacterSet &converter);
/** get cardinality of this sequence
* @return number of items in this sequence
*/
virtual unsigned long card() const;
/** insert the given item at the start of the item list maintained by this sequence.
* Ownership of the item, which must be allocated on the heap, is transferred to the sequence.
* @param item pointer to DcmItem instance allocated on the heap, must not be NULL.
* @return EC_Normal if successful, an error code otherwise
*/
virtual OFCondition prepend(DcmItem *item);
/** insert the given item at the given position within the item list maintained by this sequence.
* Ownership of the item, which must be allocated on the heap, is transferred to the sequence.
* @param item pointer to DcmItem instance allocated on the heap, must not be NULL.
* @param where index of the item after or before which the new item is to be inserted.
* Value must be < card() or equal to DCM_EndOfListIndex.
* @param before indicates whether the new item should be inserted before or after the item
* identified by "where"
* @return EC_Normal if successful, an error code otherwise
*/
virtual OFCondition insert(DcmItem *item,
unsigned long where = DCM_EndOfListIndex,
OFBool before = OFFalse);
/** insert the given item at the end of the item list maintained by this sequence.
* Ownership of the item, which must be allocated on the heap, is transferred to the sequence.
* @param item pointer to DcmItem instance allocated on the heap, must not be NULL.
* @return EC_Normal if successful, an error code otherwise
*/
virtual OFCondition append(DcmItem *item);
/** insert new item a current position.
* The current position is stored internally in the 'itemList' member variable.
* @param item new item to be inserted
* @param before flag indicating whether to insert the item before (OFFalse) or
* after (OFTrue) the current position
* @return status, EC_Normal upon success, an error code otherwise
*/
virtual OFCondition insertAtCurrentPos(DcmItem *item,
OFBool before = OFFalse);
/** access an item from the sequence. This method returns a pointer to one
* of the items in the list, and not a copy.
* @param num index number of item, must be < card()
* @return pointer to item if found, NULL if num >= card()
*/
virtual DcmItem *getItem(const unsigned long num);
/** this method enables a stack based, depth-first traversal of a complete
* hierarchical DICOM dataset (that is, classes derived from DcmItem or
* DcmSequenceOfItems). With each call of this method, the next object
* in the tree is located and marked on the stack.
* @param stack "cursor" for current position in the dataset. The stack
* will contain a pointer to each dataset, sequence, item and element
* from the main dataset down to the current element, and is updated
* upon each call to this method. An empty stack is equivalent to a stack
* containing a pointer to this object only.
* @param intoSub if true, the nextObject method will perform a hierarchical
* search through the dataset (depth-first), if false, only the current
* container object will be traversed (e.g., all elements of an item
* or all items of a sequence).
* @return EC_Normal if value length is correct, an error code otherwise
*/
virtual OFCondition nextObject(DcmStack &stack, const OFBool intoSub);
/** this method is only used in container classes,
* that is, DcmItem and DcmSequenceOfItems. It returns a pointer to the
* next object in the list AFTER the given object. If the caller passes NULL,
* a pointer to the first object in the list is returned. If the given object
* is not found, the given object is the last one in the list or the list is empty,
* NULL is returned.
* @param obj pointer to one object in the container; we are looking for the
* next entry after this one. NULL if looking for the first entry.
* @return pointer to next object in container or NULL if not found
*/
virtual DcmObject *nextInContainer(const DcmObject *obj);
/** remove item from list. If found, the item is not deleted but
* returned to the caller who is responsible for further management of the
* DcmItem object.
* @param num index number of item, must be < card()
* @return pointer to DcmItem if found, NULL otherwise
*/
virtual DcmItem *remove(const unsigned long num);
/** remove item from list. If found, the item is not deleted but
* returned to the caller who is responsible for further management of the
* DcmItem object.
* @param item pointer to item to be removed from list
* @return pointer to item if found, NULL otherwise
*/
virtual DcmItem *remove(DcmItem *item);
/** check if this sequence is empty
* @param normalize not used for this class
* @return true if sequence is empty, i.e. has no items, false otherwise
*/
virtual OFBool isEmpty(const OFBool normalize = OFTrue);
/** clear (remove) attribute value
* @return EC_Normal if successful, an error code otherwise
*/
virtual OFCondition clear();
/** check the currently stored element value
* @param autocorrect correct value length if OFTrue
* @return status, EC_Normal if value length is correct, an error code otherwise
*/
virtual OFCondition verify(const OFBool autocorrect = OFFalse);
/** a complex, stack-based, hierarchical search method. It allows for a search
* for a DICOM object with a given attribute within a given container,
* hierarchically, from a starting position identified through a cursor stack.
* @param xtag the DICOM attribute tag we are searching for
* @param resultStack Depending on the search mode (see below), this parameter
* either serves as an input and output parameter, or as an output parameter
* only (the latter being the default). When used as an input parameter,
* the cursor stack defines the start position for the search within a
* hierarchical DICOM dataset. Upon successful return, the stack contains
* the position of the element found, in the form of a pointer to each dataset,
* sequence, item and element from the main dataset down to the found element.
* @param mode search mode, controls how the search stack is handled.
* In the default mode, ESM_fromHere, the stack is ignored on input, and
* the search starts in the object for which this method is called.
* In the other modes, the stack is used both as an input and an output
* parameter and defines the starting point for the search.
* @param searchIntoSub if true, the search will be performed hierarchically descending
* into the sequences and items of the dataset. If false, only the current container
* (sequence or item) will be traversed.
* @return EC_Normal if found, EC_TagNotFound if not found, an error code is something went wrong.
*/
virtual OFCondition search(const DcmTagKey &xtag, // in
DcmStack &resultStack, // inout
E_SearchMode mode = ESM_fromHere, // in
OFBool searchIntoSub = OFTrue); // in
/** this method loads all attribute values maintained by this object and
* all sub-objects (in case of a container such as DcmDataset) into memory.
* After a call to this method, the file from which a dataset was read may safely
* be deleted or replaced. For large files, this method may obviously allocate large
* amounts of memory.
* @return EC_Normal if successful, an error code otherwise
*/
virtual OFCondition loadAllDataIntoMemory(void);
/** Copy numBytes bytes of data from the attribute value in byteOrder byte order
* to targetBuffer, starting at byte offset offset of the attribute value.
* This method does not cause the complete attribute value to be read into
* main memory. Subsequent calls for the same partial value may cause repeated
* access to file if the attribute value is kept in file.
* @param targetBuffer pointer to target buffer, must not be NULL.
* Buffer size must be at least numBytes bytes.
* @param offset byte offset within the attribute value from where to start
* copying
* @param numBytes number of bytes to copy.
* @param cache file cache object that may be passed to multiple subsequent calls
* to this method for the same file; the file cache will then keep a file
* handle open, thus improving performance. Optional, may be NULL
* @param byteOrder byte order desired byte order of attribute value in memory buffer.
* Default is the local byte order of the machine.
* @return EC_Normal upon success, an error code otherwise
*/
virtual OFCondition getPartialValue(void *targetBuffer,
const Uint32 offset,
Uint32 numBytes,
DcmFileCache *cache = NULL,
E_ByteOrder byteOrder = gLocalByteOrder);
protected:
/** This function reads tag and length information from inStream and
* returns this information to the caller. When reading information,
* the transfer syntax which was passed is accounted for. If the
* transfer syntax shows an explicit value representation, the data
* type of this object is also read from the stream. In general, this
* function follows the rules which are specified in the DICOM standard
* (see DICOM standard (year 2000) part 5, section 7) (or the corresponding
* section in a later version of the standard) concerning the encoding
* of a dataset.
* @param inStream The stream which contains the information.
* @param xfer The transfer syntax which was used to encode the
* information in inStream.
* @param tag Contains in the end the tag that was read.
* @param length Contains in the end the length value that was read.
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition readTagAndLength(DcmInputStream &inStream, // inout
const E_TransferSyntax xfer, // in
DcmTag &tag, // out
Uint32 &length); // out
/** helper function for read(). Create sub-object (item, item delimiter or sequence delimiter) of the
* appropriate type depending on the tag.
* @param subObject upon success, a pointer to the newly created object is returned in this parameter
* @param newTag tag of the sub-object to be created
* @param newLength length of the sub-object to be created
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition makeSubObject(DcmObject *&subObject,
const DcmTag &newTag,
const Uint32 newLength);
/** helper function for read(). Create sub-object (item or pixel item)
* and call read() for this sub-object.
* @param inStream The stream which contains the information.
* @param newTag attribute tag for sub-object
* @param newLength length of the sub-object to be created
* @param xfer The transfer syntax which was used to encode
* the information in inStream.
* @param glenc Encoding type for group length; specifies
* what will be done with group length tags.
* @param maxReadLength Maximum read length for reading an attribute value.
* @return status, EC_Normal if successful, an error code otherwise
*/
OFCondition readSubItem(DcmInputStream &inStream, // inout
const DcmTag &newTag, // in
const Uint32 newLength, // in
const E_TransferSyntax xfer, // in
const E_GrpLenEncoding glenc, // in
const Uint32 maxReadLength = DCM_MaxReadLength); // in
/** helper function for search(). May only be called if item list is non-empty.
* Performs hierarchical search for given tag and pushes pointer of sub-element
* on result stack if found
* @param tag tag key to be searched
* @param resultStack upon successful return, pointer to element pushed onto this stack
* @param searchIntoSub flag indicating whether recursive search is desired
* @return EC_Normal if tag found and stack modified, EC_TagNotFound if tag not found and stack unmodified
*/
virtual OFCondition searchSubFromHere(const DcmTagKey &tag, // in
DcmStack &resultStack, // inout
const OFBool searchIntoSub); // in
/// the list of items maintained by this sequence object
DcmList *itemList;
private:
/** static helper method used in writeSignatureFormat().
* This function resembles DcmObject::writeTagAndLength()
* but only writes the tag, VR and reserved field.
* @param outStream stream to write to
* @param tag attribute tag
* @param vr attribute VR as reported by getVR
* @param oxfer output transfer syntax
* @return EC_Normal if successful, an error code otherwise
*/
static OFCondition writeTagAndVR(DcmOutputStream &outStream,
const DcmTag &tag,
DcmEVR vr,
const E_TransferSyntax oxfer);
/** flag used during suspended I/O. Indicates whether the last item
* was completely or only partially read/written during the last call
* to read/write.
*/
OFBool lastItemComplete;
/** used during reading. Contains the position in the stream where
* the sequence started (needed for calculating the remaining number of
* bytes available for a fixed-length sequence).
*/
offile_off_t fStartPosition;
/** true if this sequence has been instantiated while reading an UN element
* with undefined length
*/
OFBool readAsUN_;
};
#endif // DCSEQUEN_H