DcmSwift

DcmSwift is a (partial, work in progress) DICOM implementation written in Swift. It aims to provide minimal support for the DICOM standard, focusing primarily on the DICOM file format implementation. Other aspects of the standard like networking and imaging will certainly be addressed later.

Requirements

• MacOS 10.13
• Xcode 12.4
• Swift 5.3

Dependencies

• IBM-Swift/BlueSocket (networking)
• pointfreeco/swift-html (HTML rendering of DICOM SR)

Dependencies are managed by SPM.

Disclamer

DcmSwift is not a medical imaging nor diagnosis oriented library and is not intented to be used as such. It focuses on the computing aspects of the DICOM standard, and provide a powerful set of tools to deal with DICOM files at the atomic level. The authors of this source code cannot be held responsible for its misuses or malfunctions, as it is defined in the license below.

Overview

DcmSwift is written in Swift 5.3 and mainly rely on the Foundation core library, in order to stay as compliant as possible with most of the common Swift toolchains.

A minimal DICOM specification is embed within the DicomSpec class itself. It provide a large set of tools to manipulate UIDs, SOP Classes, VRs, Tags and more DICOM specific identifiers.

With the DicomFile class you can read/write standard DICOM files (even some broken ones!). It provides an abstract layer through the DataSet class and several tools to manipulate inner data. Such objects can be exported to several formats (raw data, XML, JSON) and translated to several Transfer Syntaxes.

The library also comes with a set of helpers to ease the manipulation of DICOM specific data type like dates, times, endianness, etc. The whole API want to stay as minimal as it is possible (despite the whole DICOM standard wildness), and still giving you a decent set of features to deal with it in a standard and secure way.

DcmSwift is widely used in the DicomiX application for macOS, which is available here. The app is mainly developed as a showcase of concepts implemented by the DcmSwift library.

Use DcmSwift in your project

DcmSwift relies on SPM so all you have to do is to declare it as a dependency of your target in your Package.swift file:

dependencies: [
    .package(name: "DcmSwift", url: "http://gitlab.dev.opale.pro/rw/DcmSwift.git", from:"0.0.1"),
]

...

.target(
    name: "YourTarget",
    dependencies: [
        "DcmSwift"
    ]

If you are using Xcode, you can add this package by repository address.

DICOM files

Read a DICOM file

Read a file:

let dicomFile = DicomFile(forPath: filepath)

Get a DICOM dataset attribute:

let patientName = dicomFile.dataset.string(forTag: "PatientName")

Write a DICOM file

Set a DICOM dataset attribute:

dicomFile.dataset.set(value:"John^Doe", forTagName: "PatientName")

Once modified, write the dataset to a file again:

dicomFile.write(atPath: newPath)

DataSet

Read dataset

You can load a DataSet object manually using DicomInputStream:

let inputStream = DicomInputStream(filePath: filepath)

do {
    if let dataset = try inputStream.readDataset() {
        // ...
    }
} catch {
    Logger.error("Error")
}

DicomInputStream can also be initialized with URL or Data object.

Create DataSet from scratch

Or you can create a totally genuine DataSet instance and start adding some element to it:

let dataset = DataSet()

dataset.set(value:"John^Doe", forTagName: "PatientName")
dataset.set(value:"12345678", forTagName: "PatientID")

print(dataset.toData().toHex())

Add an element, here a sequence, to a dataset:

dataset.add(element: DataSequence(withTag: tag, parent: nil))

DICOMDIR

Get all files indexed by a DICOMDIR file:

if let dicomDir = DicomDir(forPath: dicomDirPath) {
    print(dicomDir.index)
}

List patients indexed in the DICOMDIR:

if let dicomDir = DicomDir(forPath: dicomDirPath) {
    print(dicomDir.patients)
}

Get files indexed by a DICOMDIR file for a specific PatientID:

if let dicomDir = DicomDir(forPath: dicomDirPath) {
    if let files = dicomDir.index(forPatientID: "198726783") {
        print(files)
    }
}

DICOM SR

Load and print SR Tree:

if let dicomFile = DicomFile(forPath: dicomSRPath) {
    if let doc = dicomFile.structuredReportDocument {
        print(doc)
    }
}

Load and print SR as HTML:

if let dicomFile = DicomFile(forPath: dicomSRPath) {
    if let doc = dicomFile.structuredReportDocument {
        print(doc.html)
    }
}

Networking

DICOM ECHO

Create a calling AE, aka your local client (port is totally random and unused):

let callingAE = DicomEntity(
    title: callingAET,
    hostname: "127.0.0.1",
    port: 11112)

Create a called AE, aka the remote AE you want to connect to:

let calledAE = DicomEntity(
    title: calledAET,
    hostname: calledHostname,
    port: calledPort)

Create a DICOM client:

let client = DicomClient(
    callingAE: callingAE,
    calledAE: calledAE)

Run C-ECHO SCU service:

if client.echo() {
    print("ECHO \(calledAE) SUCCEEDED")
} else {
    print("ECHO \(callingAE) FAILED")
}

See source code of embbeded binaries for more network related examples (DcmFind, DcmStore).

Using binaries

The DcmSwift package embbed some binaries known as DcmPrint, DcmAnonymize, DcmEcho, etc. which you can build as follow:

swift build

To build release binaries:

swift build -c release

Binaries can be found in .build/release directory. For example:

.build/release/DcmPrint /my/dicom/file.dcm

Unit Tests

Before running the tests suite, you need to download test resources with this embedded script:

./test.sh

Run the command:

swift test

Documentation

Documentation can be generated using jazzy:

jazzy \
  --module DcmSwift \
  --swift-build-tool spm \
  --build-tool-arguments -Xswiftc,-swift-version,-Xswiftc,5

Or with swift doc:

swift doc generate \
    --module-name DcmSwift Sources/DcmSwift/Data \
    --minimum-access-level private \
    --output docs --format html

Side notes

For testing/debuging networking

Very useful DCMTK arguments for storescp program that show a lot of logs:

storescp 11112 --log-level trace

Another alternative is storescp program from dcm4chee (5.x), but without the precision DCMTK offers.

storescp -b [email protected]:11112

DCMTK proposes also a server, for testing cfind program:

dcmqrscp 11112 --log-level trace -c /path/to/config/dcmqrscp.cfg

All the executables from both DCMTK and dcm4chee are very good reference for testing DICOM features.

Contributors

• Rafaël Warnault [email protected]
• Paul Repain [email protected]
• Colombe Blachère

License

MIT License

Copyright (c) 2019 - OPALE [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.