Documentation

Products and editions

PrologicSign PACS is sold as six products, each in three editions: Developer, Pro and Enterprise. The product decides which programs and modules you get. The edition decides which features of those modules are switched on. All six products run on Windows and come from one installer.

The six products

The installer has a Product page. A silent install passes PRODUCT=<code>. The license, not the installer, decides what runs: a page or program that is installed but not in your license shows "Not in your product".

The three editions

A feature only works if your product has the module it comes with. For example, Enterprise does not add a viewer to the PACS product: for that, choose a product with the Viewer module. A custom name and logo on a Pro or Enterprise license still shows "Powered by PrologicSign" on the About and license page, with the copyright notices and license terms.

The lists above are the seeded plans. Plans can be changed in the license server's admin, and each computer's license is what counts. Plans that are not published yet show "coming soon" on the Pricing page; contact us about those.

Feature by product

Each cell shows the lowest edition that includes the feature in that product. A Developer key has every feature of its product, for its term.

Basic viewer and full viewer

Router mode (Router without PACS)

The Router product has no archive. It runs in router mode, enforced by the service:

• Forward, then delete. Every routed image is deleted once all its forwards have succeeded, whatever the routing rule says.
• Safety buffer. In the RouterMode section of settings.json: SentRetentionDays (default 0, delete at once), KeepFailedImages (default true: an image whose forward failed for good stays until it is replayed and sent, or deleted by hand), FailedRetentionDays (default 30, used only when failed images are not kept), SweepIntervalMinutes (default 15).
• Images that match no rule are kept and appear in the transit list.
• No query/retrieve. Other systems cannot search or retrieve from a router. The Studies page is the transit queue.
• Setup. The storage folder is called the transit folder, and the wizard needs at least one forward destination. Finish creates the rule "Forward everything" to those destinations without a local copy, and switches routing on.
• When a paid license ends or cannot check in, the router keeps working for 7 more days (for a missed check-in, 7 days after the offline grace). After that it refuses new images and still forwards what is in its queue until the queue is empty. A license revoked by the server refuses new images at once. An ended Developer router key stops everything.

With PACS + Router, or the all-in-one, router mode does not apply: the archive keeps images as your routing rules and retention settings say. Routing rules, morph profiles and the router queue need the Router module; without it, routing rules are not applied and the admin app shows those pages as "Not in your product".

Viewer alone

The Viewer product installs the viewer only: no service, no admin app and no setup wizard. It activates in the viewer itself (Activate... in the toolbar), online with the key, or offline with a request file and the license file from the portal. Activating needs administrator rights once.

• Other PACS is a list of connections (name, AE title, host, port, calling AE title, C-GET or C-MOVE) to search any vendor's PACS with C-FIND at study and series level.
• Retrieve uses C-GET (preferred, no inbound port) or C-MOVE. For C-MOVE the viewer opens its own small C-STORE receiver on a configurable port, default 11113, only while a move runs; the other PACS must know the viewer's AE title, address and port.
• Cache. Retrieved studies go into a bounded cache, default 4096 MB. The least recently opened studies are removed first, and Clear cache empties it.
• Not available without a service: the study list of a PrologicSign PACS, writing reports, and the cloud buttons. Reporting and cloud export are not part of the Viewer product, also not in Enterprise.
• Not done yet: DICOM TLS. The TLS switches are disabled in 1.0.0.

One license key per computer

• One key unlocks every module of its product. The service, the admin app and the viewer on a computer share that one activation, so you never need a second key for the viewer or the router.
• A move to another product or edition keeps the same key. The change arrives at the next check-in, or at once with Check in now on the License page. A license on an offline computer needs a new license file.
• If the new product needs a program that is not installed yet (for example the viewer), uninstall and install again with the new product. A plain uninstall keeps the license and the data.
• Each license covers the number of machines in its plan, one by default. Free a machine in the customer portal before moving to a new computer.

Evaluating: free Developer keys

A key is needed from day one. To evaluate a product, get a free Developer key from dicomkit.plogic.dev: all the features of that product, on 1 computer, for 7 days, renewable once, not for production. Then buy a Pro or Enterprise key.

With no active key the service answers C-ECHO only and receives nothing, images already stored stay on disk, and the admin app opens the License page. On a viewer-only computer the viewer opens local files in basic mode, with Activate...

Administrator guide

Day-to-day running of PrologicSign PACS 1.0.0 on a Windows server: connecting devices, storage, backup, watching the service, mail and branding. Installation and the setup wizard are on the install page.

Everything here is done in the PrologicSign PACS Admin app, which asks for administrator rights when it starts. Where a setting has no page in the app, this guide says so and shows the entry in C:\ProgramData\PrologicSign\PACS\settings.json. Stop the service before you edit that file by hand.

Network: AE title, port and firewall

These are on the Settings page, under This PACS on the network.

Every device that sends to this PACS needs this PACS's AE title, IP address and port. A device that retrieves with C-MOVE must also be added here as a destination.

The setup wizard can add the Windows Firewall rule, for Domain and Private networks only. To add it by hand, in an administrator PowerShell:

New-NetFirewallRule -DisplayName "PrologicSign PACS (DICOM)" -Direction Inbound -Protocol TCP -LocalPort 11112 `
  -Action Allow -Profile Domain,Private
# Better: allow only your modality and PACS subnets
#   -RemoteAddress 10.20.0.0/16,10.30.5.0/24

Windows allows outbound connections by default; check any network firewall between the servers in both directions. To see whether the port is listening: Get-NetTCPConnection -LocalPort 11112 -State Listen.

Saving a changed AE title, port, listen address, AE check or transfer syntax list restarts the DICOM listener, and the page asks you to confirm first. Devices retry during the restart. Destinations, the duplicate policy and a storage folder change take effect without restarting it.

Destinations and C-ECHO tests

A destination is another DICOM node this PACS sends to. The same list decides who may receive a C-MOVE: the PACS only sends to the address configured here, never to an address taken from the request.

On the remote node, register this PACS (AE title, IP address and port) as a known node. Most PACS refuse unknown callers.

Test opens a connection and sends a C-ECHO:

DICOM TLS: not in this release

The app shows the controls, a Secure DICOM (TLS) section on the Settings page and a Use TLS switch on each destination, but they are disabled in 1.0.0 and cannot be turned on.

Do not turn TLS on by hand in settings.json either. Both ports start together or not at all, and TLS cannot start in this release, so the PACS would stop listening on the normal port as well.

Until TLS is available, keep DICOM on a trusted network, restrict the port with firewall rules, and use a VPN for any link that leaves your network.

The TLS code is written and tested against a DicomKit 1.0.1 preview, and is designed for a second port (default 2762) beside the plain one, TLS 1.2 and 1.3, a server certificate from the Windows store or a .pfx file, optional client certificates, and per-destination settings. None of it is active in 1.0.0.

Transfer syntaxes

The transfer syntax is how image data is encoded. It is agreed per connection. By default this PACS accepts:

Any storage SOP class is accepted. Images are stored exactly as received, with no decompression or recompression. A device that offers only a syntax missing from the list has that part of its request refused; configure it to also offer Explicit VR Little Endian.

On the Settings page, under Accepted transfer syntaxes, you can tick every syntax DicomKit knows, which adds JPEG Extended, JPEG Lossless (process 14), JPEG-LS near-lossless and the other HTJ2K variants. Saving restarts the DICOM listener.

Decompression loses nothing from the stored data, but a lossy JPEG image stays lossy: it is decompressed to the pixels it holds. This release decompresses only; it does not recompress an image to another compressed syntax.

For a viewer that accepts compressed images but cannot display them, a destination can always be sent uncompressed. There is no switch for this on the Destinations page: set "SendUncompressed": true on that destination's entry in settings.json.

Storage layout

C:\ProgramData\PrologicSign\PACS\
  settings.json          all settings (passwords and connection strings encrypted)
  pacs.db                built-in database (with pacs.db-wal, pacs.db-shm)
  logs\                  service logs
  health\                health.json, the latest health snapshot
  support\               support bundles (newest 5)
  branding\              your logo and icon (white label)
  spool\                 large incoming data sets while they are received
  studies\               default storage folder
    <StudyInstanceUID>\
      <SeriesInstanceUID>\
        <SOPInstanceUID>.dcm
    .incoming\           files being written; renamed into place when complete

• Each file is a standard DICOM Part 10 file, exactly as received. Any DICOM tool can open it.
• A half-received image is never visible. Leftover .partial files in .incoming\ after a crash are safe to delete while the service is stopped.
• Free space: incoming images are refused when free space drops below the Minimum free space on the Settings page (default 2,048 MB). Senders are told to retry.
• The same image received twice: by default the new copy replaces the stored file. The other choice keeps the stored file and discards the new copy. Both are reported to the sender as success and written to the activity log.
• A corrected resend (same SOP Instance UID with a different Study or Series UID) moves the image to its new study and series.
• Folders the service creates for patient data are limited to SYSTEM and Administrators. A storage folder that already exists keeps its permissions, so set them yourself.
• The database stores each file's path relative to the storage folder, so moving the folder needs no database change.

Moving the storage folder

For example, to a new data disk E:\PacsStudies. The service never moves images itself; you copy them. This method has no gap, because the service is stopped for the whole move:

1. Stop the service: Stop-Service PrologicSignPacs. Devices queue their images and retry.
2. Copy with permissions and time stamps:
   robocopy C:\ProgramData\PrologicSign\PACS\studies E:\PacsStudies /E /COPY:DATS /DCOPY:DAT /R:1 /W:1 /XD .incoming /LOG:C:\Temp\pacs-move.log
3. Check the log shows 0 failed files, and compare the file count and size of both folders.
4. Make sure SYSTEM and Administrators have full control on the new folder and ordinary users have no access. It holds patient images.
5. In settings.json, set Storage.Directory to the new folder, with doubled backslashes: "Directory": "E:\\PacsStudies".
6. Start the service: Start-Service PrologicSignPacs. Open a study or run a C-MOVE from a workstation to confirm images are found.
7. Delete the old folder only after a backup has run on the new location.

From the Settings page instead. With the service running, you can change Storage folder and save, and it applies at once. To protect you, the change is accepted only if the index is empty or a sample of the oldest and newest 50 index entries is found in the new folder. Otherwise the PACS keeps the current folder and tells you why. Images received after your copy still land in the old folder, so run the same robocopy command once more after saving.

Network shares work, but local disks or a SAN volume are preferred. The service runs as LocalSystem and reaches a share as the computer account (DOMAIN\PACSSERVER$), so grant that account access. The free-space check cannot read a share, so a full share shows up as write failures instead of a clean "storage full" refusal.

Backup and restore

Back up three things together: the database, the storage folder and settings.json, plus the branding\ folder if you use your own logo. The index and the files must match: an index entry whose file is missing makes C-MOVE fail for that image.

The PACS has no built-in backup. Use your own backup tools, as follows.

Order

Best, with a short maintenance window:

1. Stop the service: Stop-Service PrologicSignPacs. Devices queue their images and retry later.
2. Back up the database, then the storage folder and settings.json.
3. Start the service: Start-Service PrologicSignPacs.

Without stopping, back up the database first, then the storage folder. Images arriving in between are then in the file backup but not the index backup; the sender can resend them. The opposite order gives index entries without files, which is the harmful case.

Exclude studies\.incoming\, studies\.deleting\ and spool\ from the file backup.

Database backup per engine

Restore

1. Stop the service.
2. Restore the database, the storage folder and settings.json from the same backup set.
3. On a different server, saved secrets cannot be read, because they are encrypted for the original machine. Enter them again: the database connection string (the built-in database needs none), the SMTP password and any cloud target credentials. Each license also covers one machine, so free its seat in the customer portal and activate it on the new server.
4. Start the service, then check the Health page, the activity log and a C-FIND from a workstation. Retrieve a study with C-MOVE to confirm its files are there.

If a device still holds images that are missing after a restore, resend them from that device. The index check that finds such gaps has no page in the admin app in this release.

The Health page

Health answers two questions: is the PACS receiving images, and is anything wrong? It updates every 5 seconds. The headline reads like "Last image received 2 min ago from CT1". A status strip shows the same summary above every page of the app.

There are six lights, each with plain-language reasons. The overall state is the worst light.

A Queue light reading "Routing not in use" is normal when you have no routing rules.

The page also shows 24-hour graphs of images per hour and memory, images per sending device, the DICOM listeners and recent warnings and errors. Copy status puts a text summary on the clipboard for a ticket.

For monitoring tools: C:\ProgramData\PrologicSign\PACS\health\health.json is the latest snapshot, rewritten every sample. A read-only named pipe, \\.\pipe\PrologicSign.PACS.Status.v1, gives any local user one line of JSON with the lights, headline, last image time and images in the last hour, and no patient data. It is not reachable over the network. Fatal errors also go to the Windows Application event log, source "PrologicSign PACS", event ID 1000.

Memory: if the service stays above its limit (a quarter of the RAM, at least 1 GB, at most 8 GB) for 5 minutes, it logs a warning, raises the memory alert and frees memory. If that is not enough, it restarts its DICOM listener at a moment with no images being received. It never cuts off an image in progress: if no quiet moment comes, the restart is postponed.

The "images not arriving" alert

The Images arriving light turns amber when a device goes quiet during hours you expect work. By default that is Monday to Friday, 07:00 to 20:00 server local time, at least one image every 30 minutes from any device. If email alerts are on you also get a mail such as "No images received from CT1 for 45 min", and a "Resolved" mail when images come back or the window ends.

Change the windows in settings.json; there is no page for them in this release. A clinic that closes on some days, or does not reach one image per 30 minutes, should change this or it will see false warnings.

"Health": {
  "ImageArrival": {
    "Enabled": true,
    "SendAlert": true,
    "Windows": [
      {
        "Name": "CT1 day shift",
        "Days": [ "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" ],
        "Start": "07:00",
        "End": "20:00",
        "MaxQuietMinutes": 45,
        "CallingAeTitle": "CT1"
      }
    ]
  }
}

• You can list several windows, for example one per modality. Leave out CallingAeTitle to count images from any device.
• A window may cross midnight (22:00 to 06:00); it belongs to the day it starts on. The same start and end time means the whole day.
• Quiet time is counted from the last matching image, but never from before the window opened or the service started.
• "Enabled": false turns the warning off; the light then only shows the last image time.

Logs and the support bundle

The Logs page filters by level, date, AE title, connection id and text, has a live tail that refreshes every 2 seconds, and exports what is shown. Follow this connection shows one connection's whole journey, from the device connecting to the images being indexed.

For more detail, set Logging.MinimumLevel or Logging.DicomTrace in settings.json. They are read when the service starts, and trace output is verbose, so turn it off afterwards.

Patient names are never written to the service log, but UIDs and AE titles are. The activity log holds AE titles and UIDs too, and the Studies page shows patient names. Treat all of these as patient data.

Support bundle

Create support bundle on the Health page makes a zip for PrologicSign support, kept in C:\ProgramData\PrologicSign\PACS\support (newest 5). It contains:

• the logs of the last 7 days, up to 300 MB;
• the health snapshot;
• settings.json with every password, protected value, token and key replaced by "(removed)";
• versions and environment details (product, DicomKit, .NET, Windows, memory, disks, time zone).

It contains no images. It does contain the UIDs and AE titles in the logs, so handle it under your own data rules.

Email (SMTP) and alerts

You enter your mail server once, on the Email (SMTP) page. It is used for emailing studies, for reports (Enterprise) and for admin alerts. The PACS does not provide a mail service of its own.

Email alerts

Alerts are off until you switch on Send email alerts on the Email alerts page and add recipients. A problem is checked every 60 seconds. While it lasts, the same alert repeats at most once an hour, and a "Resolved" mail follows when it clears. All alert mail is capped at 30 per hour. The subject carries your site name (default: the computer name).

White label

On the Branding page you can show your own name, logo and colour in the admin app, the setup wizard, the viewer, PDF reports and alert emails. Every field is optional; an empty field keeps the PrologicSign default.

• Which plans: your branding is shown with an active Pro or Enterprise license. With a Developer key you can fill in the page and preview it, but the apps show PrologicSign branding. If the license stops being active, PrologicSign branding returns; your saved branding is kept.
• What stays: the About and license page keeps "Powered by PrologicSign", the copyright notices and the license terms.
• What does not change: the installer, the Windows service name, the program and data folder names, and the Start menu entries still say PrologicSign.
• Reset to PrologicSign removes all of your branding.
• Backups: the logo and icon are PNG files in the branding\ folder, so include it in your backups.

PrologicSign Viewer

The PrologicSign Viewer is a Windows desktop app for DICOM images. It opens studies from your PrologicSign PACS, from files, folders and CDs on the computer, and from other PACS systems over DICOM. The installer adds it to the Start menu and the desktop as PrologicSign Viewer on every product that includes the Viewer module.

Basic viewer and full viewer

Your license decides what the viewer can do. The edition is shown at the right of the second toolbar.

• Pro: the basic viewer.
• Enterprise and Developer: the full viewer.
• Not activated (no PACS or Router service, and no active license on this computer): the basic viewer for files, folders and CDs on this computer, with an Activate... button on the toolbar. Other PACS is not available until the computer is activated.
• A license without the Viewer module: the app shows "Your license doesn't include the viewer" and nothing else.

Anything your license does not include stays visible with a lock and the tooltip "Available in Enterprise". Choosing it only shows that message in the status line.

On a computer with a PACS or Router service the viewer uses the service's license, so no extra key is needed. Until a key is active there, the viewer shows "Your license doesn't include the viewer": activate the key on the License page of the admin app. If the service cannot be reached, the viewer says so in a banner and falls back to the license file on the computer or to the basic viewer.

Activating a viewer-only computer

Press Activate... on the toolbar and enter your PrologicSign Viewer key (one key per computer). Without internet, save an activation request to a file, upload it in the customer portal, and import the license file you get back. Activating needs administrator rights once: if you are told so, right-click the viewer, choose Run as administrator and activate again. The viewer then reopens with your license.

The window

• First toolbar: open, PACS list, Other PACS, cloud, layout, left-drag tool, window presets, zoom and orientation, cine, shortcuts.
• Second toolbar: measurement tools, save and export, Download, Email, Report, and your edition.
• PACS studies panel (left): the study search. The toolbar's PACS studies button shows or hides it.
• Series strip: one thumbnail per series of what is open.
• Viewports: the images. The active viewport has a brighter border, and toolbar actions and keys apply to it.
• Status line (bottom): what the viewer is doing, and the window, zoom and pixel value of the active viewport.

Each viewport shows the DICOM details in its corners: patient (top left), study (top right), modality, series, image and frame number (bottom left), and pixel value under the mouse, window, zoom and orientation (bottom right).

Opening studies from the PACS

From the PACS studies panel

1. Enter any of patient name (part of the name; * and ? are wildcards), patient ID, accession, modality and a date range. Today sets both dates to today and Clear empties the fields.
2. Press Search. With every field empty you get the newest studies. The list shows the first 100 matches; narrow the search to see others.
3. Double-click a study, or select it and press Open.

Open in viewer, from the admin app

On the Studies page of the admin app:

• the Open in viewer button opens the focused study at the series and image shown in the details panel;
• double-click a study, or right-click it and choose Open in viewer, for the whole study;
• double-click a series, or right-click it and choose Open this series in the viewer;
• double-click an image thumbnail to go to that image.

If a viewer is already open for your Windows user, it comes to the front and shows the study, so you do not collect windows. If the requested series or image is not in the study, the first series is shown and the status line says why.

What the PACS list needs

• The same computer as the PACS. The viewer reads the images directly from the PACS storage folder. On any other computer, use Other PACS to retrieve studies over DICOM.
• Administrator rights. Only Administrators and SYSTEM may talk to the PACS service, and the storage folder is normally restricted the same way. On a computer with a PACS or Router service the viewer therefore asks for administrator rights when it starts (a Windows User Account Control prompt). Answer Yes, or the list cannot reach the service.

Local files, folders and CDs

• Open files (Ctrl+O): pick one or more DICOM files. The dialog lists .dcm and .dicom; choose All files for files without an extension.
• Open folder (Ctrl+Shift+O): every DICOM image in the folder and its subfolders.
• CD, DVD or USB from another system: use Open folder on the drive, or Open files with All files and pick the DICOMDIR file.
• Drag and drop: drop files or folders from Windows Explorer onto a viewport.
• Command line: Prologic.Pacs.Viewer.exe file1.dcm folder2.

Each open replaces what was on screen. The viewer sorts the images into series by their DICOM headers, so file names and folder layout do not matter. Within a series the order is by instance number, then file name.

• A DICOMDIR is used only to find the folder: the viewer reads every image in the folder that holds it and below, and does not read the index itself.
• At most 20,000 files are read per open; the status line tells you when that limit was reached.
• Files that are not DICOM images are skipped and counted in the status line. DICOM files without pixels, such as reports and presentation states, are left out.

Demo mode

"C:\Program Files\PrologicSign\PACS\Viewer\Prologic.Pacs.Viewer.exe" --demo starts the full viewer on synthetic images of made-up patients. It needs no service and no license.

Other PACS: search and retrieve from any PACS

The Other PACS button on the toolbar opens a window that searches any DICOM PACS and retrieves studies to this computer. It works with or without a PrologicSign PACS service here.

1. Press Add and fill in a name, the PACS AE title, its host name or IP address, and its port. Our AE title can stay empty to use the viewer AE title. Press Save.
2. Press Test to send a DICOM echo (C-ECHO).
3. Enter patient name, ID, accession, modality or dates, and press Search (C-FIND). The first 500 matches are shown.
4. Select a study to see its series. Press Retrieve and open study or, for one series, Retrieve and open series.

The other PACS must allow this computer to query and retrieve; add the viewer's AE title there if it keeps a list of allowed callers.

• Retrieved studies stay in %LocalAppData%\PrologicSign\Viewer\Cache until the limit removes them. Clear cache deletes them all. They are not added to your PACS.
• Connections are saved for each Windows user in %LocalAppData%\PrologicSign\Viewer\pacs-connections.json. They hold no passwords.
• DICOM over TLS is not available in this release. The switch is disabled in 1.0.0.

Layouts and series

• Press 1x1, 1x2, 2x2 or 3x3 on the toolbar (Ctrl+1 to Ctrl+4). The numbers are rows x columns.
• Full viewer: type rows and columns (1 to 5 each) in the two boxes and press the check mark.
• Existing viewports keep their series; new ones get the next series not yet shown.
• Drag a series thumbnail onto a viewport, or double-click a thumbnail to show it in the active viewport.
• Double-click a viewport to show it alone; double-click again to go back.
• Click a viewport, or press Ctrl+Tab, to make it active.

Moving through images

The mouse wheel or the arrow keys step one image at a time. A multi-frame image counts each frame as a step. Page Up and Page Down jump 10; Home and End go to the first and last.

The Left drag list on the toolbar sets what the left mouse button does: Pan (the default), Zoom, WindowLevel or Scroll. The right and middle buttons do not change.

Window/level

• Right-drag in a viewport: horizontal movement changes the width, vertical movement changes the level.
• Presets: choose one from the Window list or press a function key. They are CT values in Hounsfield units and are of most use on CT.
• 0 or the toolbar's image-window button goes back to the window stored in the image.
• I inverts the grey scale.

Zoom, orientation and display quality

• Zoom with Ctrl+wheel (around the mouse), Ctrl+left-drag, or + and -, from 2% to 4000%. Pan with the middle button.
• F fits the image to the viewport. 1 shows one image pixel per screen pixel.
• R and Shift+R rotate by 90 degrees; H and V flip.
• Esc resets the viewport: window, invert, rotation, flips and zoom. It also stops cine.
• P switches every viewport between smooth display (the default) and pixel-exact, where each screen pixel shows one stored pixel.

Images with non-square pixels are shown in their true proportions.

Measurements and annotations

Pick a tool under Measure on the second toolbar, then draw with the left mouse button. The tool stays selected so you can draw another. Off gives the left button back to the navigation tool.

• Select: click a measurement to select it, drag a handle to reshape it, drag its body to move it. Delete removes the selected one.
• Esc abandons a drawing and leaves measuring. Press it again to reset the viewport.
• Measurements belong to one frame of one image.

Where the numbers come from

• Pixel Spacing in the image gives millimetres.
• Imager Pixel Spacing only also gives millimetres, with a warning that the size is measured at the detector and not corrected for magnification.
• No spacing: lengths and areas are in pixels, with a warning.
• Values use the image's rescale slope and intercept, and the Rescale Type as the unit (HU for CT when the type is missing).
• On colour images Probe gives no value and ROIs give only the area, with the message "Pixel values are not available for this image."

Where measurements are saved

In the full viewer each change is saved automatically to %LocalAppData%\PrologicSign\Viewer\Annotations, one file per image, and comes back when that image is opened again by the same Windows user on the same computer. Measurements are not written into the DICOM files, not stored in the PACS, and not sent with an export, Download or Email.

Cine

Full viewer. Space or the toolbar's play button plays the active viewport's series in a loop and stops it. The speed starts at 10 frames per second and can be 1 to 60: use the box on the toolbar, the slider that appears on the viewport while playing, or [ and ]. If images take longer to draw than the speed allows, frames are skipped rather than delayed. A series with one frame does not play.

Save, export and share

Cloud: Open from cloud and Send to cloud (Enterprise)

These two toolbar buttons appear only when the PACS or Router service on this computer is reachable and its license includes cloud export (Enterprise and Developer). They do not appear on a viewer-only computer. An administrator first adds the cloud targets (Amazon S3, Azure Blob or Google Drive) in the admin app under Cloud targets. The service keeps the cloud credentials and the viewer never holds them.

Open from cloud

1. Choose a cloud target, enter patient name, ID, accession, modality or dates if you want, and press Search. The first 500 matches are shown.
2. For DICOM files that other software put in the target, enter a folder (or leave it empty for the whole target) and press Scan folder. Only their headers are read, and they are listed as Scanned.
3. Double-click a study or press Open study. The first image of each series appears as soon as it has arrived, and the rest follows. Stop cancels.

Downloaded studies go to a cache in your Windows profile that only your Windows user can read. It is encrypted with Windows EFS where that is available; on Windows Home, FAT/exFAT or network drives it is not encrypted, but it is still restricted to you. By default the cache is emptied when the viewer closes. It is also capped at 5 GB and 7 days.

Send to cloud

Uploads the study on screen to a cloud target. The PACS service uploads it from its own storage, so the study must have been opened from the PACS list.

Keyboard and mouse shortcuts

F1 or the keyboard button on the toolbar shows this list in the app. Keys do nothing while you are typing in a box.

Not in this release

• Windows only.
• No multi-planar reconstruction (MPR), 3D or image fusion.
• No hanging protocols, and no linked scrolling between viewports.
• DICOM presentation states are not applied, and measurements are not saved as DICOM objects.
• No DICOM over TLS for Other PACS.
• No DICOMDIR is written on export.
• The PACS studies panel works only on the computer that runs the PACS.

PrologicSign Router

The Router receives DICOM images, decides with your rules where each one goes, and forwards it from a queue that survives restarts and outages. It can change header tags on the way, decompress for destinations that need it, and upload to cloud storage.

Which products include routing

Rules, the queue, tag morphing and transcoding are in the Pro and Enterprise editions. Cloud targets are Enterprise only. A Developer key includes everything on one machine, and is not for production.

How an image travels

1. The image is received by C-STORE, stored and indexed.
2. If routing is on (Routing rules page, switch Routing is on), every enabled rule is evaluated.
3. Each forward a matching rule asks for becomes one queue entry per image and destination, saved in the database.
4. The worker sends due entries in batches and records each image as sent, failed or given up.

Images that match no rule stay where they are and are not forwarded.

Rules and conditions

Rules are checked by priority, lowest number first; rules with the same priority keep their list order. On the Routing rules page you drag a rule to change its order and can switch a rule off without deleting it. A rule with no conditions matches every image.

Text conditions use one of these operators: Equals, Contains, StartsWith, Wildcard (* and ?), Regex (.NET syntax, 100 ms limit per match; a match that runs out of time counts as no match and is reported as a warning) and Exists. Text is compared without regard to case unless Match case is on. Separate several values with \: the condition matches if any value of the tag matches any entry. A missing tag never matches.

The rule editor combines a rule's conditions with ALL (AND) or ANY (OR). The rule format in settings.json also supports NOT and nested groups, up to 8 levels deep.

What a matching rule does

• Destinations: one or more DICOM destinations and, on Enterprise, cloud targets.
• Keep local copy: on keeps the image here as well; off is forward only.
• Morphing profile: optional header changes applied to the forwarded copies.
• Delay: wait before forwarding, in seconds. 0 sends at once; the maximum is 7 days.
• Stop processing: when this rule matches, no later rule is checked.

When several rules match

• Every matching rule adds its forwards, until a matching rule with Stop processing ends the evaluation.
• The queue holds one waiting entry per image and destination. If two rules send the same image to the same destination, the higher-priority rule decides the profile and delay. Do not rely on two rules to deliver two differently morphed versions to one destination.
• An image received again while it is still waiting is not queued twice.

A rule with errors (an unknown destination or profile, a bad regular expression) is left out and reported, while the other rules keep working. Use Test rules on the same page to try the rules against a stored study or pasted header values: it shows which rules match, why, and where the image would go. Nothing is sent.

Keep local or forward only

• The image is removed only when every matching rule is forward only. One matching rule that keeps the image keeps it.
• Nothing is removed while any forward is waiting, retrying or has given up. A forward that gave up keeps the image here, and a later successful replay removes it.
• Every removal is written to the activity log.

Router mode

A license with the Router module and no PACS module runs in router mode. The storage folder is the transit folder, the Studies page shows images in transit, and the service answers no C-FIND, C-MOVE or C-GET.

• Every routed image is deleted after its forwards have all been sent, whatever the rule says. Keep local copy has no effect here.
• Images that match no rule are kept and show in the transit list, so check that your rules cover what you receive.
• The setup wizard needs at least one destination and creates the rule "Forward everything", without a local copy, and switches routing on.

A safety buffer in settings.json, section RouterMode, decides how long images stay:

The queue, retries and Replay

The queue is a table in the PACS database, with one entry per image and destination, so entries survive a restart or a power cut.

Three tries per image

By default each image gets at most 3 tries per destination: the first try, a second try 30 seconds later, and a third 60 seconds after that. If the third fails, the image moves to the failed list as given up.

These images go straight to the failed list with no further tries:

• tag morphing failed or was refused (see Tag morphing);
• the image is no longer stored;
• the destination has been removed from the configuration (add it again and replay).

When the service stops normally, batches in progress are handed back and that try is not counted.

The failed list and Replay

The Router queue page has one card per destination, with its counts and last error, and a list of failed sends grouped by study.

• Replay selected, or the replay button on a row, sends those studies again now.
• Replay all failed on a destination card sends everything failed for that destination again.
• Replay works on both failed and given-up entries, and gives each one a fresh 3 tries.
• Delete removes entries from the list only. The stored images are not touched, and those entries will not be sent.
• Replays and deletions are written to the activity log. Replay needs the Router module.

Email alerts are available for a failing destination (on by default, after 15 minutes) and for images given up (on by default). Set them on the Email alerts page.

Queue settings

These are in settings.json, section RouterQueue. There is no page for them in the admin app.

Tag morphing profiles

A profile is an ordered list of header changes, applied to the copies a rule forwards to DICOM destinations. Create profiles on the Morph profiles page. Check validates the steps, and Preview tries them on a stored study without sending anything.

• The image stored here is never changed, and pixel data is never changed.
• Steps that name a tag work on the top level of the data set.
• If a new value does not fit the image's character set, the image is converted to UTF-8.
• The new UIDs are remembered in memory for the most recent 100,000 or more UIDs per profile and are not saved. After a service restart, images of a study already partly sent get different new UIDs, so the destination may see them as a separate study.
• Each morphed image gets a line in the activity log with its changes. The values can hold patient data, so they go to the activity log only, never to the service log.

An image is never sent unmorphed by mistake

If the image could carry data the profile was meant to remove, it is not forwarded. It goes to the failed list with the reason, in these cases:

• a step fails, or a regular expression exceeds its time limit (250 ms per value by default);
• the profile named by the rule no longer exists: fix the rule and replay;
• tag morphing is not licensed;
• the rule that queued the image has been deleted.

The profile is read when the image is sent, so changing a profile also affects images already waiting. Replaying an image whose rule was deleted is refused again, so finish or replay what is waiting before you delete a rule. Manual send applies no morphing.

Transcoding

Transcoding in this release means decompression only. Images are never compressed or recompressed. For each DICOM destination the worker does this:

1. It offers each compressed image in its stored transfer syntax. If the destination accepts that syntax, the image goes unchanged.
2. Otherwise the image is decompressed to Explicit VR Little Endian and sent on a second association. The stored image is not changed.

• Decodable: RLE Lossless, JPEG Baseline and Extended, JPEG Lossless, JPEG-LS and JPEG 2000. An image in any other compressed syntax, or one that cannot be decoded, fails like any other send.
• After a lossy codec, Lossy Image Compression is set to "01" on the sent copy.
• Images over 64 MB are decompressed through the spool folder rather than in memory.
• For a destination that accepts compressed images but cannot show them, set SendUncompressed to true on that destination in settings.json, and every image is decompressed before sending. There is no switch for this in the admin app.
• Morphing runs first, then any decompression. Cloud targets get the stored file, with no decompression.

Cloud targets (Enterprise)

Add targets on the Cloud targets page. In the rule editor they appear among the destinations as "Cloud: name", and on the Studies page through Send to cloud.... The service does the uploads. Credentials are stored encrypted for this machine (Windows DPAPI).

• What is uploaded: the stored DICOM file byte for byte, or a de-identified copy (names, IDs, dates and private tags removed or replaced, UIDs remapped per target). You can also add a JPEG of the first frame.
• Path: a template below the optional prefix. The default is {PatientID}/{StudyDate}_{AccessionNumber}/{SeriesNumber}/{SOPInstanceUID}.dcm. Values are cleaned to letters, digits, ., - and _.
• Routing to a cloud target uses the same queue, 3 tries, failed list and Replay as DICOM. It always uploads single files; ZIP per study is for manual sends only. Up to 4 files upload at once per target (Cloud.MaxParallelUploads).
• A morphing profile is not applied to cloud uploads. To remove identifying data, set the target's content to the de-identified copy. Review the result against your own requirements before relying on it.
• A target that is switched off keeps its entries waiting. So do all cloud entries while the license does not include cloud export. If a target is deleted, its waiting entries go to the failed list.
• A forward-only image is removed only after its cloud forwards have been sent too.

When a paid license ends

The grace is 7 days after the license end date. If the license could not check in, it is 7 days after the 7-day offline grace ends. These periods are built into the product and cannot be changed in the settings.

PrologicSign Router (no PACS module)

PACS + Router, and PACS + Router + Viewer

The service status says what has happened, and email alerts are sent when the grace starts and when it ends. A Developer key that has ended stops everything, with no grace.

Known limits in 1.0.0

• Forwarding decompresses only. It cannot convert to another compressed syntax.
• Images received in Explicit VR Big Endian or Deflated Explicit VR Little Endian can fail or be corrupted when forwarded to a destination that accepts the same syntax. The PACS does not accept those syntaxes by default; if you add them in Settings they are marked "cannot be forwarded".
• DICOM TLS for forwarding needs a DicomKit build with TLS, which the 1.0.0 build does not include.
• The 1.0.0 release test run did not exercise cloud targets against real storage. Use Save and test on each target, and send a test study before relying on it.

Licensing and activation

One license key per computer, a free Developer key to evaluate, and activation with or without internet. Everything you manage is in the customer portal.

One key per computer

• One key unlocks every module of its product. The service, the admin app and the viewer on a computer share one activation, so you never enter a second key for the viewer or the router.
• The key carries the product (PACS, Router, Viewer, PACS + Viewer, PACS + Router, or PACS + Router + Viewer) and the edition (Developer, Pro or Enterprise).
• A license covers one computer unless your plan has more seats. The license page in the portal shows the seats in use.
• The admin app and the viewer show what is licensed. In the admin app, open the License page. A page for a module your product does not include stays in the menu and says so.

Evaluating: the free Developer key

A key is needed from day one. To evaluate, get a free Developer key from dicomkit.plogic.dev, then buy a Pro or Enterprise key for production.

• A Developer key has all the features of the product, on 1 computer, for 7 days.
• You can renew it once, for another 7 days, on the license page in the portal.
• It is for evaluation and testing only, not for production.

With no active key

The computer is locked until a key is activated: nothing is received and only DICOM C-ECHO still answers. Images already stored stay on disk. The admin app opens the License page. A viewer-only computer opens local files, folders and CDs in basic mode, with Activate... in the toolbar. Managed updates need an activated license.

Activating online

Keys are in the customer portal. The computer must reach https://dicomkit.plogic.dev on port 443.

1. Open the admin app and go to the License page. On a new installation you can also enter the key in the License step of the setup wizard.
2. Paste the key and press Activate online.

On a viewer-only computer there is no admin app. Press Activate... in the viewer toolbar instead. This needs administrator rights once, because the license is kept for every user of the computer. A PACS installed later on that computer uses the same activation.

Activating offline

For a computer with no internet connection:

1. On the License page press Save activation request... (viewer-only: Save request file...). The file starts with PLGICREQ1.
2. On a computer with internet, sign in to the customer portal and open the license. Under Offline activation, upload the file or paste its text, then press Create activation file.
3. Carry the .lic file back and press Import license file...

An offline activation of a Pro or Enterprise license uses one seat and is valid until the license's end date, with no check-in. After a renewal or a change of product or edition, make a new file the same way. The license must be active and not expired to make a file.

Computer ID

A license is bound to one computer through its Computer ID, shown with a copy button on the License page. Support may ask for it. It is made from the computer name, the operating system and the Windows machine GUID, and it contains no user name, so every Windows user of the computer shares the license.

Renaming the computer or re-imaging Windows changes the ID. The license then no longer matches. Free the old entry in the portal and activate again.

Daily check-in and 7-day offline grace

Yearly subscriptions and Developer keys activated online confirm themselves with the license server. Offline files for Pro and Enterprise do not check in.

• The PACS service checks in once every 24 hours and retries an hour after a failure. Check in now on the License page does it at once.
• If the server cannot be reached, nothing changes for 7 days after the last confirmed check-in. After 48 hours without one, the License page says how long the license will keep working offline.
• After those 7 days the license counts as not checked in and the rules for an ended license apply. The next confirmed check-in switches everything back on.
• If the server refuses the license (revoked, suspended, expired, or its seat was freed), the same rules apply at once, with no grace.

Upgrading on the same key

You keep the same key when you move to another edition or product. To change, use the subscription page in the customer portal where your plan offers it, or contact us.

• Online: the new product and features arrive at the next check-in with nothing to enter. Check in now on the License page does it at once. On a downgrade, the modules or features no longer included switch off the same way.
• Offline: make a new license file in the portal and import it, as in offline activation.

Installing more than the license includes does no harm: those parts show as not in your product. To change which modules are installed, uninstall and install again with the other product.

What happens when a license ends

This table is for a Pro or Enterprise license that passed its end date, did not check in within the offline grace, or was refused by the server. The admin app shows a renewal warning from 14 days before the end date. Renewing or activating again switches everything back on. Images kept in a PACS archive are not deleted because a license ended.

• For a missed check-in, the 7 days in this table start when the 7-day offline grace ends.
• On a computer with a PACS or Router service, the viewer follows the service's license. While no key is active, or that license does not include the viewer, the viewer shows Your license doesn't include the viewer.
• On products with a router, and with email alerts set up, a mail is sent when the 7 days start and when forwarding pauses or the router starts refusing images.
• A Developer key that ended stops everything, on every product, because it is not for production. Only C-ECHO still answers, and a viewer-only computer keeps basic mode. This is the same lock as a computer with no key.

Moving to another computer

1. Sign in to the customer portal and open the license.
2. Under Machines, press Deactivate next to the old computer. Hover over its ID to compare it with the Computer ID on the License page.
3. Activate the same key on the new computer, online or offline.

The old computer stops being licensed the next time it checks in, and the rules for a refused license apply to it. Activating a key that has no free seat is refused until you free one.

You can free up to 2 computers per seat in any 30 days, and the portal shows how many are left. If you need to move one sooner, contact support. Activating again on the same computer, for example after reinstalling the PACS on it, does not use another seat as long as its Computer ID is unchanged.

Managed updates

PrologicSign decides per license which version is offered and whether it is only announced or installed automatically. The PACS service asks the license server once a day, at a random minute between 02:00 and 04:00 local time. Check for updates... on the License page asks at once.

• An install never starts while a DICOM association is open. Installing closes the admin app and restarts the service, and DICOM connections are refused for a few minutes. Your data is kept.
• An update is accepted only when the server's answer is signed by PrologicSign and the downloaded package matches its published SHA-256 checksum. Anything else is refused.
• The 1.0.0 installer is not yet signed with a Windows code-signing certificate. The next release will be, and installed systems receive it through the normal automatic update.
• No updates are offered to a revoked or suspended license, to a computer with no active key, or on a computer without internet access. Those computers, and viewer-only computers (managed updates run in the service), are updated by running a newer installer from the Downloads page.

Help

Report a problem in the issue tracker or contact support, and include the Computer ID if the question is about one computer.

DICOM conformance statement

This statement follows the structure of DICOM PS3.2. It is written from the source code of release 1.0.0 and does not replace testing with your own devices.

1. Overview

The PACS service receives DICOM instances from modalities and other systems, stores them on a Windows disk, indexes them in a database (built-in SQLite, SQL Server, MySQL or PostgreSQL) and lets workstations query and retrieve them. Staff can send studies to other DICOM nodes. Products with the Router module also forward received instances by rule.

The table shows the service with every module. Section 2 shows what each product includes.

DICOMweb is not part of this product.

2. Differences by product

Router. The listener is the same, so a Q/R presentation context can still be accepted during negotiation. Every C-FIND (worklist included), C-MOVE and C-GET is then answered 0x0124 (Refused: Not authorized).

Viewer. The viewer's "Other PACS" function needs an activated license. It has no listener of its own apart from the temporary receiver below.

• Default calling AE title: PROLOGIC_VIEWER, or a title set per connection.
• C-ECHO; C-FIND with Study Root at STUDY and SERIES level.
• C-GET with Study Root (preferred, no inbound port), proposing a fixed list of common storage SOP classes with SCP role selection.
• C-MOVE with Study Root: a C-STORE receiver opens on port 11113 (configurable) only while the move runs, and requires the called AE to match. The other PACS must know the viewer's AE title, address and port.
• Transfer syntaxes accepted for retrieved images: Explicit and Implicit VR Little Endian, Deflated Explicit VR Little Endian, JPEG Baseline, Extended, Lossless (.57 and .70), JPEG-LS Lossless and Near-Lossless, JPEG 2000 (both) and RLE.

Editions. Pro, Enterprise and Developer do not differ in DICOM services, except that report PDFs (section 15) need Enterprise or Developer with the PACS module.

License state. The checks apply to every operation, not only at negotiation. C-ECHO always answers. Without a valid license C-STORE, C-FIND, C-MOVE and C-GET are answered 0x0124. See the Licensing guide for the expired and grace-period rules.

3. Implementation model

The service has one Application Entity, by default PROLOGIC_PACS. It runs inside the Windows service and listens on one TCP port (default 11112). The same AE, or a per-destination calling AE alias, acts as SCU.

• Store: a received instance is written to <storage>\<Study UID>\<Series UID>\<SOP Instance UID>.dcm and added to the index. The response is sent only after both succeed, so an instance can be queried and retrieved as soon as its C-STORE response has been sent.
• Query: C-FIND is answered from the index.
• Retrieve: C-MOVE and C-GET send the stored files. C-MOVE decompresses when needed (section 11).
• Send: an operator picks studies and a destination in the admin app.
• Forward: received instances that match a routing rule are queued and sent to the rule's destinations.
• Verify: the admin app's Test button sends a C-ECHO.

4. SOP classes

The SCP has no list of storage SOP classes. Every abstract syntax that is not Verification and not a Q/R or worklist SOP class is accepted as a storage SOP class. That includes all standard, retired and private storage classes. As SCU the service sends whatever SOP class is stored.

Side effect: a context for a non-storage SOP class (for example Modality Performed Procedure Step or Storage Commitment) is also accepted during negotiation. No N-service is implemented, so an N-CREATE, N-SET, N-ACTION or N-EVENT-REPORT is answered 0x0211 (Unrecognized Operation). Do not take the accepted context as support for the service.

5. Transfer syntaxes

Accepted by default for storage, in the service's order of preference. The requester's order is ignored: the first entry of this list that the requester proposed is chosen.

• Also selectable in Settings, off by default: JPEG Extended (.4.51), JPEG Lossless Process 14 (.4.57), JPEG-LS Near-Lossless (.4.81), HTJ2K RPCL (.4.202) and HTJ2K (.4.203).
• Cannot be accepted: MPEG-2, MPEG-4 and HEVC video syntaxes, JPIP and private syntaxes.
• "Prefer compressed" setting (off by default): moves the compressed syntaxes ahead of the uncompressed ones, so an image offered both ways is stored as the sender compressed it.

6. Association policies

Number of associations

Timers

After A-RELEASE-RP this version closes the connection at once.

7. Association initiation

Send (manual send and router forward)

Calling AE: the destination's calling AE alias when set, otherwise the PACS AE title. Called AE: the destination's AE title. The work is done in passes, each on its own association, and at most 127 SOP classes per association. Verification is always proposed, in Implicit VR Little Endian.

1. As stored (default): per compressed syntax found in the batch, one association proposing only that syntax. Instances the destination accepts in it are sent unchanged.
2. Uncompressed: one association proposing Explicit and Implicit VR Little Endian carries the uncompressed instances and every compressed instance not sent in step 1, decompressed to Explicit VR Little Endian.

A destination set to "send uncompressed" skips step 1, for systems that accept compressed images but cannot show them.

• Decompression available for: RLE, JPEG Baseline, Extended, Lossless (.57 and .70), JPEG-LS (both) and JPEG 2000 (both). JPEG-LS and JPEG 2000 need those features in the DicomKit runtime license.
• Not available for: HTJ2K, and pixel data with Bits Allocated 1. An instance that cannot be delivered as stored or decompressed fails, and the rest continue.
• Never compressed. The SOP Instance UID is kept. After a lossy codec, Lossy Image Compression is set to "01".
• Status: 0x0000 and any 0xBxxx warning count as sent. Any other status is recorded as failed and the next instance is sent.
• Lost association: a new one is opened and that file is sent once more.
• Manual send: up to 3 connection attempts; reports the totals and the first 200 failures.
• Router: a persistent queue retries failed instances with back-off and moves them to a dead-letter list after the configured attempts (default 3).
• Tag morphing (Router): changes only the forwarded copy, before any decompression. If morphing fails, the original is never sent instead.

Verify

C-ECHO with Verification in Implicit VR Little Endian. Success only on status 0x0000.

8. Association acceptance

AE title and other checks, in the order applied

Presentation contexts

• An even presentation context ID is rejected (result 2). A duplicate ID aborts the association.
• Verification: the first syntax of the accepted list that the requester proposed.
• Q/R FIND, MOVE, GET: Explicit or Implicit VR Little Endian only. Any other syntax alone: result 4.
• Storage: the first syntax of the accepted list (section 5) that the requester proposed. None proposed: result 4.
• Modality Worklist FIND: the context may be accepted, but this product has no worklist and every worklist C-FIND returns 0x0000 with no matches. Do not configure modalities to use this AE as a worklist provider.

9. Verification and Storage SCP

C-ECHO is answered 0x0000.

Storage conformance level: 2 (Full). The data set is stored bit for bit as received, in the negotiated transfer syntax, with a PS3.10 file meta header added (Source AE Title = the calling AE). No attribute is changed, removed or added, no image is decompressed or recompressed on receipt, and private attributes are kept.

• Retention: files stay until an administrator removes them. An optional retention policy is off by default. A Router without the PACS module deletes an image once it has been forwarded (section 2).
• Index: long values are cut to the column size in the index only: Patient Name and Referring Physician 324 characters; Patient ID, Accession Number, Study and Series Description 64; Study Time, Modality, Body Part and Patient Sex 16. The file keeps the full value.
• Duplicates (same SOP Instance UID): by setting, the new copy replaces the stored one (default) or the stored copy is kept. Both answer 0x0000 and write an activity-log entry. A resend with a corrected Study or Series Instance UID moves the instance in the index and deletes the old file.

The service never returns a warning status (0xB000, 0xB006, 0xB007) for C-STORE.

10. Query/Retrieve SCP: C-FIND

Not in the Router product. Models and levels: Patient Root (PATIENT, STUDY, SERIES, IMAGE) and Study Root (STUDY, SERIES, IMAGE). Relational queries are not negotiated, but the SCP does not require the unique keys of higher levels: a SERIES or IMAGE query without a Study Instance UID searches all studies.

Any key not listed below is ignored for matching and returned zero-length. When such a key carried a matching value, pending responses use 0xFF01 instead of 0xFF00. Only the keys present in the request are returned, plus Specific Character Set and Query/Retrieve Level.

Study ID (0020,0010), a required key at Study level, is not in the index: it cannot be matched and is returned zero-length.

11. Query/Retrieve SCP: C-MOVE and C-GET

Not in the Router product. The Query/Retrieve Level and the unique key of that level are required: Patient ID, Study Instance UID, Series Instance UID or SOP Instance UID. Each may be a list. A missing unique key is answered 0xA900. Instances are sent by Series Number, then Instance Number. At most 65,535 instances per request. C-CANCEL stops after the current instance.

C-MOVE destination. The Move Destination must exactly (case-sensitively) equal the AE title of a destination configured in the admin app. Host and port come from that configuration, never from the request. An unknown destination gets 0xA801.

• All sub-operations of one C-MOVE use one new association. Calling AE: the PACS AE title. Called AE: the destination AE title.
• Contexts: for each SOP class, one proposing Explicit and Implicit VR Little Endian, plus one per other stored syntax.
• Each C-STORE carries Move Originator AE Title and Message ID.
• Before the move, one short association per compressed syntax asks the destination what it accepts (10 s connect, 15 s response; the answer is kept 5 minutes). Instances it refuses as stored are decompressed to Explicit VR Little Endian (limits as in section 7). A destination set to "send uncompressed" gets all decompressible images decompressed.

C-GET. Instances are sent on the requester's association, always as stored. The requester must propose a context for each SOP class it wants to receive, with SCP role selection, and accept the stored syntax. C-GET does not decompress: instances without a usable context fail as sub-operations.

12. Network interfaces and configuration

TCP/IP over any network adapter Windows supports, DICOM Upper Layer per PS3.8. IPv4; IPv6 when the listen address is an IPv6 address (:: listens on both).

Settings are made in the admin app and stored in %ProgramData%\PrologicSign\PACS\settings.json.

The other limits and timers in section 6 are DicomKit defaults and cannot be configured in this version.

13. Media and character sets

Media interchange. No PS3.10 media profile is claimed.

• Import (PACS module) reads a folder or the files a DICOMDIR lists.
• The viewer opens files, folders, DICOMDIR and CDs.
• Export writes PS3.10 files to a folder but no DICOMDIR: DicomKit 1.0.0 cannot write one.

Received instances. Any Specific Character Set value is accepted and stored unchanged. To index text, these are decoded: ISO_IR 6 (or absent), 100, 101, 109, 110, 126, 127, 138, 144, 148, 166, ISO_IR 13, ISO_IR 192 (UTF-8), GB18030, GBK, the ISO 2022 forms of the single-byte sets, ISO 2022 IR 87 and ISO 2022 IR 149. When (0008,0005) has several values, the last is used for the whole value, so text that switches character sets with escape sequences may be indexed incorrectly. An unknown value is decoded as Latin-1.

C-FIND. Request values are decoded with the request's character set. Responses are always UTF-8 (ISO_IR 192); a requester that cannot read UTF-8 will show non-ASCII characters wrongly.

C-MOVE, C-GET, send and forward keep the instance's character set.

14. Security

• Association level: the AE title checks of section 8. C-MOVE can only send to configured destinations.
• Admin app: talks to the service only over a local named pipe; it has no network listener.
• Stored secrets: database connection strings are encrypted for the machine (Windows DPAPI).
• File paths: UIDs and AE titles from the network are never used as file paths without sanitising, and files stay inside the storage folder.

Activity log. Written to the database and shown in the admin app, kept 365 days by default (1 to 3650). Categories: Service, Receive, Send, Query, Retrieve, Settings, Security and Report. Instances received successfully are not logged one by one; they appear in the study index with the sender's AE title and time. Every C-FIND, C-MOVE, C-GET, manual send and routing batch is logged.

Rejected associations go to the service log file, not to the activity log. The product does not send IHE ATNA or DICOM PS3.15 audit messages to a syslog repository.

15. Annexes and known limitations

Created instances. The service does not change received instances. With the Reporting feature (Enterprise or Developer, PACS module) a finalized report can be stored in its study as a new Encapsulated PDF Storage instance (1.2.840.10008.5.1.4.1.1.104.1) in a new series with Modality DOC. It can be queried and retrieved like any other instance.

Private attributes. None defined. Those of received instances are stored and sent unchanged. No specialized or private SOP classes or transfer syntaxes are defined.

Known limitations of this version

1. No DICOM TLS (section 14).
2. Explicit VR Big Endian and Deflated Explicit VR Little Endian are off by default. If you add them, images received in those syntaxes may be damaged or fail when sent on, because DicomKit 1.0.0 encodes Explicit VR Little Endian on the wire even when one of those syntaxes was agreed.
3. Study ID (0020,0010) is not indexed: it cannot be matched and is returned zero-length.
4. Modality Worklist and non-storage SOP classes may be accepted during negotiation without the service being provided.
5. C-GET sends as stored and never decompresses. HTJ2K cannot be decompressed on any path. Nothing is ever compressed or recompressed.
6. C-FIND responses are always UTF-8.
7. No Storage Commitment, MPPS or worklist.

Security

This page is for the IT and security staff who review PrologicSign PACS before it goes on a hospital network. It covers what data stays on site, what leaves and when, how secrets and folders are protected, what is logged, what has been tested, and what is still missing in version 1.0.0.

What stays on your site

Images, reports and patient details are stored on your own server and database. They are never sent to PrologicSign. The product has no usage analytics or telemetry.

What leaves your site only if you set it up

These connections exist only after an administrator configures them. They go to systems you choose, not to PrologicSign.

De-identification changes DICOM tags only. It cannot remove text drawn into the image. When studies are packaged anonymised for download or email, images flagged Burned In Annotation = YES are left out. Cloud export does not check that flag, so do not rely on a de-identified cloud copy for ultrasound or scanned documents.

What is sent to the license server

The only connections to PrologicSign are the license and update requests below. They use HTTPS to dicomkit.plogic.dev (port 443). The product refuses a license server address that is not HTTPS, except on the local machine.

• Machine id: a SHA-256 hash (64 hex characters) of the machine name, the operating system and the Windows MachineGuid. It contains no user name, and the original values cannot be read from it.
• License token: a signed record of the license id, the licensee name, dates, mode, the machine id and the licensed features. It contains nothing about patients or studies.
• Never sent: images, DICOM tags, patient names or IDs, accession numbers, study counts, reports, AE titles, host names, or log files.
• IP address: as with any web request, the server sees the public IP address the request comes from. It uses this to limit the request rate.

Every token, check-in receipt and update answer must carry a PrologicSign signature, which the product verifies. A wrong or hostile server address cannot grant a license or push an update. An answer that is not signed is ignored.

Sites with no internet access can use offline activation: a person carries a request code to a computer with internet and brings back a license file. Ask for a fixed-term license, which needs no check-in. Automatic update checks are switched off with Updates.Enabled = false in settings.json.

Automatic updates: the license server decides per license whether a new version is only announced or installed automatically. An automatic install never starts while a DICOM association is open, and you can limit it to a maintenance window. The downloaded package must match the SHA-256 in the signed answer, or it is refused. If your change-control process does not allow unattended installs, set Updates.Enabled = false.

Encrypted secrets (DPAPI)

These values are encrypted with Windows DPAPI before they are written to disk:

• the database connection string;
• the SMTP password;
• the password of a TLS certificate file;
• cloud storage keys and service account files;
• the license key entered in the setup wizard.

The encryption uses DPAPI machine scope, so the service and an elevated admin app can both read the values. This has two consequences:

• A secret only works on the machine that encrypted it. After moving to a new server, enter the connection string and the other secrets again.
• Any process on that machine that can read settings.json can decrypt the values. The protection therefore rests on the folder permissions below, so do not loosen them. Use a database login with rights on the PACS database only, not sa.

Service account

The installer creates the Windows service PrologicSign PACS (service name PrologicSignPacs). It runs as LocalSystem, starts automatically (delayed start) and restarts after 1 minute on failure. The installer has no option for another account, and running under a different account has not been tested for this release. LocalSystem has full rights on the machine, so treat the server accordingly: dedicate it to the PACS where you can, and keep it patched and limited to the administrators who need it.

Folder permissions

The installer sets these permissions on C:\ProgramData\PrologicSign\PACS, with inheritance from the parent folder turned off:

• A folder the product creates later (for example a new storage folder) gets SYSTEM, Administrators and the service account only, with nothing inherited.
• A folder that already exists keeps its permissions. If you point storage at an existing folder such as D:\PACS, check its permissions yourself: the root of a data drive normally lets Authenticated Users modify files, and the product does not warn about this.
• On a network share, the share and NTFS permissions apply.
• Program files go to C:\Program Files\PrologicSign\PACS, where only administrators can write.
• On a viewer-only installation the data folder holds only the license file, and every user of the computer can read it.
• Uninstalling keeps the data unless you ask for it to be removed. A storage folder elsewhere and an external database are never touched.

Admin access: local named pipes

The admin app talks to the service over a named pipe on the same computer. The service has no web interface and no remote admin port.

• The pipe allows Administrators and SYSTEM only and denies network logons. Inheritance is off, so nothing else is added. The admin app therefore asks for administrator rights (a UAC prompt) when it starts.
• The service creates the pipe as the first instance. If another process already holds the name, the service refuses to share it.
• Requests are limited in size and time (60 seconds per request), and at most 8 admin windows can connect at once.
• A second pipe, \\.\pipe\PrologicSign.PACS.Status.v1, is read-only for signed-in local users and denied to network logons. It is used by the tray icon and returns the health lights, a headline, the last image time, the sender's AE title and the images received in the last hour. It returns no patient data, paths or settings.

Audit (activity) log

The activity log is a table in the PACS database, shown in the admin app under Activity log, where it can be filtered and exported. It records:

• queries, retrieves and sends, with the calling AE title and the number of matches or images;
• receive refusals and duplicates (successful stores are counted, not listed one by one);
• license changes, settings reloads, routing rule changes, report actions and study deletions, with the Windows user who made them.

Entries are kept for 365 days by default. You can set 1 to 3,650 days, or keep them for ever. Check this against your own retention policy.

What it does not do yet:

• It does not record the search terms of a query, or which studies and patients a retrieve or send covered.
• It does not record studies viewed in the admin app.
• Rejected connections appear in the service log, not in the activity log.
• A settings change is recorded as "settings reloaded" with the user, without old and new values.
• It has no tamper evidence. Anyone with write access to the database can change it.
• Writing an entry never holds up DICOM traffic. If the database stays locked and more than 256 entries are waiting, new entries are dropped and the number dropped is written to the service log.

Service logs

• Daily files in PACS\logs\ (service-yyyyMMdd.log, and a .clef JSON copy for tools). A file that reaches 50 MB continues in a new one, and files older than 31 days are deleted. Both limits can be changed.
• The PACS does not write patient names to the service log. An automated test stores an image with a marker patient name and confirms the name appears in none of the log files.
• Logs do contain UIDs and AE titles, which can be linked back to a study, and the local Users group can read this folder. If that does not suit your site, remove the Users entry from PACS\logs\.
• When an image cannot be parsed, the error text is stored in the activity log entry, and such text could quote a value from the file. Treat the activity log as patient data.
• Passwords and connection strings are not logged.
• Leave the Logging.DicomTrace option off unless support asks you to turn it on. It adds per-connection detail.
• Fatal errors also go to the Windows Application log, source PrologicSign PACS.

Network protection you need to set up

The DICOM defaults favour getting connected. Tighten them before going live:

1. Firewall. Allow the DICOM port only from your modality and workstation subnets. The firewall rule offered by the setup wizard is not limited by subnet, so add or replace it:

   New-NetFirewallRule -DisplayName "PrologicSign PACS (DICOM)" -Direction Inbound -Protocol TCP -LocalPort 11112 `
     -Action Allow -Profile Domain,Private -RemoteAddress 10.20.0.0/16,10.30.5.0/24

2. Allowed calling AE titles. The list is empty by default, which means any AE title is accepted. Fill it in under Settings. An AE title is a name the sender picks for itself, so this is a filter and not authentication.
3. Listen address. The default 0.0.0.0 means every network card. Enter the address of the imaging network instead.
4. Keep DICOM traffic on a trusted network. It is not encrypted in 1.0.0. Across sites, use a VPN or an encrypted tunnel.
5. Consider "Keep existing" for duplicates. The default, Replace, lets any allowed sender overwrite an image it knows the SOP Instance UID of.
6. Outbound: allow HTTPS to dicomkit.plogic.dev for online activation, check-in and updates, or use offline activation.

Allowing the unsigned installer

The 1.0.0 installer is not yet signed with a Windows code-signing certificate. Windows SmartScreen may show "Windows protected your PC" and "Unknown publisher". This is expected for this version. A Publisher rule cannot match the file, so allow it by hash or by path. You never need to add a certificate to a trusted store for this product, and the installer never installs one.

1. Check the file. Download PrologicSignPACS-1.0.0-x64.msi and SHA256SUMS.txt only from https://pacs.plogic.dev. The first line of SHA256SUMS.txt is the checksum of the MSI, and the other lines are the program files it installs.

   $expected = (Get-Content .\SHA256SUMS.txt -TotalCount 1).Split(' ')[0]
   $actual   = (Get-FileHash .\PrologicSignPACS-1.0.0-x64.msi -Algorithm SHA256).Hash
   if ($actual -eq $expected) { 'MSI checksum OK' } else { 'MISMATCH - do not install' }

2. Unblock the file, only after the checksum matches. This removes the "from the internet" mark that makes SmartScreen ask. Deployment tools that run msiexec /i ... /qn (Intune, Configuration Manager, Group Policy) do not show SmartScreen.

   Unblock-File .\PrologicSignPACS-1.0.0-x64.msi

3. AppLocker. Add a hash rule for the MSI, and a hash or path rule for the program folder. Run this on a test machine after installing, and review the XML before you merge it:

   $info  = @(Get-AppLockerFileInformation -Path .\PrologicSignPACS-1.0.0-x64.msi)
   $info += Get-AppLockerFileInformation -Directory 'C:\Program Files\PrologicSign\PACS' -Recurse -FileType Exe, Dll
   $info | New-AppLockerPolicy -RuleType Hash -User Everyone -Optimize -Xml | Out-File .\PrologicSignPACS-applocker.xml
   Set-AppLockerPolicy -XmlPolicy .\PrologicSignPACS-applocker.xml -Merge

   Hash rules must be renewed for every new version, including automatic updates. A path rule for %PROGRAMFILES%\PrologicSign\PACS\* does not need renewing, and only administrators can write there.
4. WDAC / App Control for Business. Build a supplemental policy from the installed program folder, using hash rules or a file-path rule. Merge it with your base policy and deploy it the usual way:

   New-CIPolicy -Level Hash -Fallback FilePath -ScanPath 'C:\Program Files\PrologicSign\PACS' -UserPEs `
       -FilePath .\PrologicSignPACS-wdac.xml
   # or a path rule:  New-CIPolicyRule -FilePathRule 'C:\Program Files\PrologicSign\PACS\*'

What protects you without the Windows certificate: the program files carry the PrologicSign strong-name signature, licenses are signed and checked by the PACS, and updates are accepted only when the update answer is signed by PrologicSign and the package matches its SHA-256. A strong name identifies the files but is not checked by Windows, so the checksum in step 1 is your check on the download.

The next release will be signed by PrologicSign Technology. A Publisher or signer rule can then replace the hash rules. If your organisation only allows signed software, contact support and we will help your IT team.

Reliability evidence

These are our own tests, run in October 2026 on a development PC (Windows 11, 32 logical CPUs, local NVMe) with synthetic data. Client and server ran on the same machine. They show how the service behaved under these conditions and do not predict results on your hardware.

Soak test, 150 minutes, real service host with the built-in SQLite database, while the PC was also running other builds:

• 64,368 images acknowledged (34.0 GiB), with 8,427 C-FIND, 423 C-GET and 282 C-MOVE operations alongside.
• 11 injected faults: database write-locked for 120 seconds, disk reaching its free-space limit, and a routing destination killed for 120 seconds. 99 transfers were also cut off mid-way.
• 0 acknowledged images lost, and no half-written files or files without an index row.
• 1,014 stores were refused and retried by the sender, nearly all of them during the disk-full faults. 4 C-FIND requests returned an error and 4 associations had to reconnect.
• Memory and handles showed no upward trend over the last hour (working set about 172 to 206 MB).

A later 10-minute run with 6 injected faults on the merged code also lost no images. The longest run on record is 150 minutes. We have no multi-day soak result.

Concurrency and bombardment tests, each followed by a full integrity check of files against the index:

This testing found 8 bugs, all fixed, including one where images could be lost from the index after a database failure when the duplicate policy was Keep existing.

Not covered:

• MySQL / MariaDB and PostgreSQL were not stress-tested, because no server was available. SQL Server was tested on LocalDB.
• A power cut between writing a file and committing its index row can leave an unindexed file. With Keep existing, a resend of that image is then acknowledged without indexing it. The index check on the Storage page repairs this.
• The connection-limit test ran at 512 associations. The shipped default is 128.

Known limitations in 1.0.0

Our code review of the product left these open. Plan for them:

• No DICOM TLS. The code is written, but 1.0.0 runs the plain port only. TLS arrives with a later DICOM library release.
• Open by default. Any AE title, every network interface. The setup wizard does not ask for an allowed list. See above.
• Allowed senders are trusted fully. Any allowed AE can query every patient, overwrite a stored image when the duplicate policy is Replace, and ask for any study to be moved to any configured destination. One request can cover a whole patient, and requests are not rate-limited per caller.
• The SOP Instance UID in the command is not compared with the one inside the file.
• Disk use. Large incoming images are spooled to the system drive before the free-space check runs, and the check is on the storage volume. Watch free space on C:. Email alerts can watch the storage, data and spool folders. Storage on a network share has no free-space check.
• Patient-level queries run one database query per patient and can be slow on a very large archive.
• Audit log gaps and the DPAPI machine-scope limit, both described above.
• No check of folder permissions at start-up or when you choose a storage folder.
• The installer is unsigned in this release.

The security review so far has been done by us. No independent penetration test or third-party audit has been carried out. PrologicSign makes no claim of compliance with, or certification under, any regulation or standard. Assessing the product against your own obligations remains with your organisation, and we will answer your security questionnaire as far as we can: contact us.

Troubleshooting

What each message means and what to do about it. The messages are written here as PrologicSign PACS 1.0.0 shows them.

First checks for any problem

1. Open PrologicSign PACS Admin and look at the Health page. It gives the current state and the reason for anything amber or red.
2. Is the service running, and is the port listening? Run these on the PACS computer (11112 is the default port):

   Get-Service PrologicSignPacs
   Get-NetTCPConnection -LocalPort 11112 -State Listen

3. Can the other device reach it? Run this on that device, or on a computer in the same network:

   Test-NetConnection pacs-host -Port 11112

4. Read the logs (below). DICOM status codes are hexadecimal: the sending device's log shows the code, and this PACS records the matching reason.

The association is rejected (before any image is sent)

To test from another computer, use any DICOM echo tool, for example DCMTK: echoscu -aet TESTSCU -aec PROLOGIC_PACS pacs-host 11112.

Test (C-ECHO) to a destination

C-STORE: receiving images

C-FIND: queries

C-MOVE and C-GET: retrieves

With C-MOVE this PACS opens a new connection to the address configured for the destination AE title and sends the images there, so the destination must be listening and must accept connections from this PACS. C-GET returns the images on the requester's own connection and needs neither a destination entry nor an inbound firewall rule on the requester's side.

Manual send. A send job ends as Completed, Completed with errors, Failed or Cancelled, and lists the first 200 per-image failures with their reason, for example refused with status 0xA700. That status is the destination's own answer, so read its log. Send jobs are kept in memory: after a service restart the list is empty and an interrupted job must be started again.

Port in use and service start-up

If the DICOM port or the database is not ready, the service does not stop. It tries again after 2, 5, 10 and 30 seconds and then every 60 seconds, and shows the reason in the admin app and the service log.

# Which program holds the port?
Get-Process -Id (Get-NetTCPConnection -LocalPort 11112 -State Listen).OwningProcess

# Which ports has Windows reserved?
netsh interface ipv4 show excludedportrange protocol=tcp

Database

While the database cannot be reached, C-STORE answers 0xA700 so that devices retry later. Short interruptions are retried automatically.

License messages

The License page in the admin app shows the current state and message. A key is needed from day one: with no active key the PACS answers C-ECHO only and receives nothing, and the admin app opens the License page. To evaluate, get a free Developer key.

The admin app asks for administrator rights

This is expected. PrologicSign PACS Admin talks to the service over a local named pipe that only Administrators and SYSTEM may use, and it can start and stop the Windows service. So it asks once at each start, with a Windows User Account Control prompt.

On a computer with a PACS or Router service, the viewer asks in the same way each time it starts. On a computer with only the viewer, activating the license needs administrator rights once.

Windows SmartScreen: "Windows protected your PC"

The 1.0.0 installer is not yet signed with a Windows code-signing certificate, so SmartScreen may show "Windows protected your PC" and "Unknown publisher". This is expected for this version and does not mean the file is unsafe. The next release is planned to be signed by PrologicSign Technology.

1. Download the installer only from https://pacs.plogic.dev, never from a link in an email or a file-sharing site.
2. Compare its SHA-256 checksum with the one published next to the download:

   Get-FileHash .\PrologicSignPACS-1.0.0-x64.msi -Algorithm SHA256

3. Run the installer as an administrator. If the message appears, click More info, check the file name, then click Run anyway.

Software deployment tools that run msiexec /i … /qn do not show SmartScreen. If your organisation allows only signed software, the Administrator guide shows how to allow this version by hash or path under AppLocker or WDAC, or contact support and we will help your IT team.

Frequently asked questions

What still works when a license ends?

A paid PACS keeps receiving images and answering query/retrieve, so a hospital never loses what modalities send. Manual send, routing, tag morphing, transcoding and the viewer stop until a key is entered. On PACS + Router products, forwarding continues for 7 more days, then pauses with the queue kept. A Router without PACS keeps receiving for 7 days; after that it refuses new images with 0x0124 and still forwards what it already holds. A license the server refused has no 7-day period. A Developer key that ended stops everything until it is renewed (once, for 7 more days) or a Pro or Enterprise key is entered.

Does it need internet access?

Not for DICOM. Subscriptions check in with the license server once a day and keep working for 7 days without a connection. A computer that is never online uses offline activation: a request code, then a license file from the customer portal.

Which ports does it use?

One inbound TCP port for DICOM, 11112 by default. Outbound connections go to your destinations, and HTTPS (443) to the license server.

Is DICOM over TLS available?

Not in 1.0.0, which uses plain TCP. Restrict who can reach the port with the firewall. An AE title allow-list is not authentication: the sender chooses its own name.

Does it offer Modality Worklist?

No. A worklist query returns no matches.

Where are my images and settings?

Under C:\ProgramData\PrologicSign\PACS\ unless you chose another storage folder: settings.json, pacs.db for the built-in database, logs\ and studies\. Images are standard DICOM files, stored as received.

Does uninstalling delete my data?

Not by default. Data is removed only if you tick "Also delete all PACS data" or use REMOVEDATA=1, and that touches only C:\ProgramData\PrologicSign\PACS. A storage folder elsewhere and an external database are never touched.

How do I move to a new computer?

Free the seat under Machines in the customer portal and activate the key on the new computer. Copy the database, storage folder and settings.json together, then enter any external database connection string again.

Sending a support bundle

A support bundle is a zip file with what support needs to diagnose a problem.

1. In the admin app open Health and click Create support bundle....
2. Choose where to save it. A copy also stays in C:\ProgramData\PrologicSign\PACS\support\, where the newest 5 are kept. The name looks like PrologicSign-PACS-support-<computer>-<date>-<time>.zip.
3. Describe the problem in the issue tracker (reports are private between you and support) or on the contact page. Say what you expected, what happened, when, and which device was involved. Both take text only.
4. Email the zip to support@plogic.dev with your license ID. Never send your license key, a password, or a connection string. If the file is too large to email, say so and ask for another way to send it.

No images or study data are included. The logs and settings can still contain AE titles, network addresses, file paths and DICOM UIDs, so handle the file as your site's policy requires.

The bundle is made by the service. If the service will not start, send the files in C:\ProgramData\PrologicSign\PACS\logs\ and any Event Log entries with ID 1000 instead. admin-errors.log is not part of the bundle, so add it when the problem is in the admin app.

PrologicSign PACS is not a medical device.

Release notes

What is in PrologicSign PACS 1.0.0, how to install the unsigned installer, and what this version does not do yet.