Parse labels in DCM files

The DCM file contains information labels related to the patient and the cause, which may or may not be used, but it is important to know. You can go to this site and check out the tag information DICOM, or the nuggets have been summarized by the author. Link.

Parsing these tags requires the dicomParser plug-in

// In this function some objects are returned, Data attributes of objects and mount the tag information cornerstone. LoadAndCacheImage (imageId). Then (img = > {cornerstone. The displayImage (img element); })Copy the code

img.data

  • ByteArray this is an array of bytes
  • Properties in byteArrayParser parse raw arrays of data
  • Elements Label information in the DCM file

The information corresponding to the tag is not expanded, and the two websites provided have explanations. For example, if you need to get the patient ID –> img.data.elements[“x00100020”], you can get a byte bit containing the beginning and end of the patient ID.

  • DataOffset The start bit in an array of bytes
  • Length Indicates the length of the patient ID
  • ID tag patients
  • Vr recognizes data types

Knowing this information, you can use the DataSet constructor provided by dicomParser to parse the tag information, or you can parse it yourself. String.fromcharcode is used for both self parsing and dicomParser parsing. First look at the source code:

The text and string in the DataSet function are roughly the same.

string

text

It’s easy to use

cornerstone.loadAndCacheImage(imageId).then(img => {
    let byteArray = img.data.byteArray,
        byteArrayParser = img.data.byteArrayParser,
        elements = img.data.elements;
    console.log(new dicomParser.DataSet(byteArray,byteArrayParser,elements).string("x00100020"));
    cornerstone.displayImage(element,img);
})
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Self analysis:

let elements = img.data.elements["x00100020"];
resolveTag(img.data.byteArray,elements.dataOffset,elements.length);
function resolveTag(byteArray, position, len) {
    let result = "";
    for (let i = 0; i < len; i++) {
        let temp = byteArray[position + i];
        result += String.fromCharCode(temp);
    }
    return result;
}
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Basic can obtain information on these, deeper or rely on their own to view the source code, try to write again.