// namespaces
var dwv = dwv || {};
dwv.dicom = dwv.dicom || {};
/**
* Immutable tag.
*
* @class
* @param {string} group The tag group as '0x####'.
* @param {string} element The tag element as '0x####'.
*/
dwv.dicom.Tag = function (group, element) {
if (!group || typeof group === 'undefined') {
throw new Error('Cannot create tag with no group.');
}
if (group.length !== 6 || !group.startsWith('0x')) {
throw new Error('Cannot create tag with badly formed group.');
}
if (!element || typeof element === 'undefined') {
throw new Error('Cannot create tag with no element.');
}
if (element.length !== 6 || !element.startsWith('0x')) {
throw new Error('Cannot create tag with badly formed element.');
}
/**
* Get the tag group.
*
* @returns {string} The tag group.
*/
this.getGroup = function () {
return group;
};
/**
* Get the tag element.
*
* @returns {string} The tag element.
*/
this.getElement = function () {
return element;
};
}; // Tag class
/**
* Check for Tag equality.
*
* @param {dwv.dicom.Tag} rhs The other tag to compare to.
* @returns {boolean} True if both tags are equal.
*/
dwv.dicom.Tag.prototype.equals = function (rhs) {
return rhs !== null &&
typeof rhs !== 'undefined' &&
this.getGroup() === rhs.getGroup() &&
this.getElement() === rhs.getElement();
};
/**
* Tag compare function.
*
* @param {dwv.dicom.Tag} a The first tag.
* @param {dwv.dicom.Tag} b The second tag.
* @returns {number} The result of the tag comparison,
* positive for b before a, negative for a before b and
* zero to keep same order.
*/
dwv.dicom.tagCompareFunction = function (a, b) {
// first by group
var res = parseInt(a.getGroup()) - parseInt(b.getGroup());
if (res === 0) {
// by element if same group
res = parseInt(a.getElement()) - parseInt(b.getElement());
}
return res;
};
/**
* Get the group-element key used to store DICOM elements.
*
* @returns {string} The key as 'x########'.
*/
dwv.dicom.Tag.prototype.getKey = function () {
// group and element are in the '0x####' form
return 'x' + this.getGroup().substring(2) + this.getElement().substring(2);
};
/**
* Get a simplified group-element key.
*
* @returns {string} The key as '########'.
*/
dwv.dicom.Tag.prototype.getKey2 = function () {
// group and element are in the '0x####' form
return this.getGroup().substring(2) + this.getElement().substring(2);
};
/**
* Get the group name as defined in dwv.dicom.TagGroups.
*
* @returns {string} The name.
*/
dwv.dicom.Tag.prototype.getGroupName = function () {
// group is in the '0x####' form
// TagGroups include the x
return dwv.dicom.TagGroups[this.getGroup().substring(1)];
};
/**
* Split a group-element key used to store DICOM elements.
*
* @param {string} key The key in form "x00280102" as generated by tag::getKey.
* @returns {object} The DICOM tag.
*/
dwv.dicom.getTagFromKey = function (key) {
return new dwv.dicom.Tag(
'0x' + key.substring(1, 5),
'0x' + key.substring(5, 9));
};
/**
* Does this tag have a VR.
* Basically the Item, ItemDelimitationItem and SequenceDelimitationItem tags.
*
* @returns {boolean} True if this tag has a VR.
*/
dwv.dicom.Tag.prototype.isWithVR = function () {
var element = this.getElement();
return !(this.getGroup() === '0xFFFE' &&
(element === '0xE000' || element === '0xE00D' || element === '0xE0DD')
);
};
/**
* Is the tag group a private tag group ?
* see: http://dicom.nema.org/medical/dicom/2015a/output/html/part05.html#sect_7.8
*
* @returns {boolean} True if the tag group is private,
* ie if its group is an odd number.
*/
dwv.dicom.Tag.prototype.isPrivate = function () {
// group is in the '0x####' form
var groupNumber = parseInt(this.getGroup().substring(2), 16);
return groupNumber % 2 === 1;
};
/**
* Get the tag info from the dicom dictionary.
*
* @returns {Array} The info as [vr, multiplicity, name].
*/
dwv.dicom.Tag.prototype.getInfoFromDictionary = function () {
var info = null;
if (typeof dwv.dicom.dictionary[this.getGroup()] !== 'undefined' &&
typeof dwv.dicom.dictionary[this.getGroup()][this.getElement()] !==
'undefined') {
info = dwv.dicom.dictionary[this.getGroup()][this.getElement()];
}
return info;
};
/**
* Get the tag Value Representation (VR) from the dicom dictionary.
*
* @returns {string} The VR.
*/
dwv.dicom.Tag.prototype.getVrFromDictionary = function () {
var vr = null;
var info = this.getInfoFromDictionary();
if (info !== null) {
vr = info[0];
}
return vr;
};
/**
* Get the tag name from the dicom dictionary.
*
* @returns {string} The VR.
*/
dwv.dicom.Tag.prototype.getNameFromDictionary = function () {
var name = null;
var info = this.getInfoFromDictionary();
if (info !== null) {
name = info[2];
}
return name;
};
/**
* Get the TransferSyntaxUID Tag.
*
* @returns {object} The tag.
*/
dwv.dicom.getTransferSyntaxUIDTag = function () {
return new dwv.dicom.Tag('0x0002', '0x0010');
};
/**
* Get the FileMetaInformationGroupLength Tag.
*
* @returns {object} The tag.
*/
dwv.dicom.getFileMetaInformationGroupLengthTag = function () {
return new dwv.dicom.Tag('0x0002', '0x0000');
};
/**
* Is the input tag the FileMetaInformationGroupLength Tag.
*
* @param {dwv.dicom.Tag} tag The tag to test.
* @returns {boolean} True if the asked tag.
*/
dwv.dicom.isFileMetaInformationGroupLengthTag = function (tag) {
return tag.equals(dwv.dicom.getFileMetaInformationGroupLengthTag());
};
/**
* Get the Item Tag.
*
* @returns {dwv.dicom.Tag} The tag.
*/
dwv.dicom.getItemTag = function () {
return new dwv.dicom.Tag('0xFFFE', '0xE000');
};
/**
* Is the input tag the Item Tag.
*
* @param {dwv.dicom.Tag} tag The tag to test.
* @returns {boolean} True if the asked tag.
*/
dwv.dicom.isItemTag = function (tag) {
return tag.equals(dwv.dicom.getItemTag());
};
/**
* Get the ItemDelimitationItem Tag.
*
* @returns {dwv.dicom.Tag} The tag.
*/
dwv.dicom.getItemDelimitationItemTag = function () {
return new dwv.dicom.Tag('0xFFFE', '0xE00D');
};
/**
* Is the input tag the ItemDelimitationItem Tag.
*
* @param {dwv.dicom.Tag} tag The tag to test.
* @returns {boolean} True if the asked tag.
*/
dwv.dicom.isItemDelimitationItemTag = function (tag) {
return tag.equals(dwv.dicom.getItemDelimitationItemTag());
};
/**
* Get the SequenceDelimitationItem Tag.
*
* @returns {dwv.dicom.Tag} The tag.
*/
dwv.dicom.getSequenceDelimitationItemTag = function () {
return new dwv.dicom.Tag('0xFFFE', '0xE0DD');
};
/**
* Is the input tag the SequenceDelimitationItem Tag.
*
* @param {dwv.dicom.Tag} tag The tag to test.
* @returns {boolean} True if the asked tag.
*/
dwv.dicom.isSequenceDelimitationItemTag = function (tag) {
return tag.equals(dwv.dicom.getSequenceDelimitationItemTag());
};
/**
* Get the PixelData Tag.
*
* @returns {dwv.dicom.Tag} The tag.
*/
dwv.dicom.getPixelDataTag = function () {
return new dwv.dicom.Tag('0x7FE0', '0x0010');
};
/**
* Is the input tag the PixelData Tag.
*
* @param {dwv.dicom.Tag} tag The tag to test.
* @returns {boolean} True if the asked tag.
*/
dwv.dicom.isPixelDataTag = function (tag) {
return tag.equals(dwv.dicom.getPixelDataTag());
};
/**
* Get a tag from the dictionary using a tag string name.
*
* @param {string} tagName The tag string name.
* @returns {object|null} The tag object or null if not found.
*/
dwv.dicom.getTagFromDictionary = function (tagName) {
if (typeof tagName === 'undefined' || tagName === null) {
return null;
}
var group = null;
var element = null;
var dict = dwv.dicom.dictionary;
var keys0 = Object.keys(dict);
var keys1 = null;
var foundTag = false;
// search through dictionary
for (var k0 = 0, lenK0 = keys0.length; k0 < lenK0; ++k0) {
group = keys0[k0];
keys1 = Object.keys(dict[group]);
for (var k1 = 0, lenK1 = keys1.length; k1 < lenK1; ++k1) {
element = keys1[k1];
if (dict[group][element][2] === tagName) {
foundTag = true;
break;
}
}
if (foundTag) {
break;
}
}
var tag = null;
if (foundTag) {
tag = new dwv.dicom.Tag(group, element);
}
return tag;
};