Office conversion

ARender converts Office documents (Word, Excel, PowerPoint, Visio, Project, Publisher, and OpenDocument formats) to PDF before rendering. The conversion is handled by the document-converter (TaskConversion) microservice, which delegates to one of three backends: LibreOffice, DirectOffice, or Microsoft Office (AROMS).

Backends overview

Backend	License	Platform	Default	Notes
LibreOffice	Free (open-source)	Linux, Windows	Yes	Ships with ARender Docker images. Broad format support.
DirectOffice	Paid add-on	Linux, Windows	No	Higher fidelity for MS Office formats. Falls back to LibreOffice for ODF formats.
Microsoft Office (AROMS)	MS Office license required	Windows only	No	Best fidelity for complex Office documents. Requires .NET 4.5 and desktop folders.

LibreOffice (default)

LibreOffice is the default conversion backend. No additional configuration is needed after a standard ARender installation.

By default, all Office MIME types are routed to LibreOffice via the genericConvertOffice factory in the document-converter configuration:

document-converter application.yaml

mimetype:
  support:
    libreoffice: "${mime.type.msoffice.word},${mime.type.msoffice.rtf},${mime.type.libreoffice.text},${mime.type.msoffice.excel},${mime.type.libreoffice.sheet},${mime.type.msoffice.powerpoint},${mime.type.libreoffice.presentation},${mime.type.msoffice.visio},${mime.type.libreoffice.graphics},${mime.type.msoffice.project}"
    directoffice: ""

LibreOffice headless options

LibreOffice runs in headless mode inside the container. If you need to tune its behavior, you can override properties in the TaskConversion application.properties file.

Conversion timeout

The default conversion timeout is 120 seconds. To change it:

document-converter application.yaml

conversion:
  job:
    timeout:
      ms: 120000

See the Document converter reference for all converter properties including LibreOffice, DirectOffice, and ImageMagick settings.

DirectOffice (paid add-on)

DirectOffice is a commercial conversion engine sold as an add-on. It provides faster, higher-fidelity conversion of Microsoft Office formats (Word, Excel, PowerPoint). For OpenDocument and other formats, it delegates to LibreOffice.

Why choose DirectOffice?

• Pros: Fast, high-quality conversion of MS Office formats. Quick issue resolution through Uxopian support. Ideal for businesses seeking consistent quality and reliable technical support.
• Cons: Paid add-on. Delegates OpenDocument formats (ODT, ODS, ODP) to LibreOffice.

Activating DirectOffice

Docker Compose

DirectOffice is pre-installed in the arender-document-converter Docker image — no binary setup is needed.

Add environment variables to the document-converter service in your docker-compose.yml:

docker-compose.yml

document-converter:
  image: artifactory.arondor.cloud:5001/arender-document-converter
  environment:
    # ... existing eureka vars ...
    # Activate DirectOffice for Word, Excel, PowerPoint
    - "DCV_MIMETYPE_SUPPORT_DIRECTOFFICE=application/msword,application/vnd.openxmlformats-officedocument.wordprocessingml.document,application/vnd.ms-word.document.macroEnabled.12,application/vnd.openxmlformats-officedocument.wordprocessingml.template,application/vnd.ms-word.template.macroEnabled.12,application/msexcel,application/vnd.ms-excel,application/x-ms-excel,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet,application/vnd.ms-excel.sheet.macroEnabled.12,application/vnd.openxmlformats-officedocument.spreadsheetml.template,application/vnd.ms-excel.template.macroEnabled.12,application/vnd.ms-powerpoint,application/vnd.openxmlformats-officedocument.presentationml.presentation,application/vnd.ms-powerpoint.presentation.macroEnabled.12,application/vnd.openxmlformats-officedocument.presentationml.template,application/vnd.ms-powerpoint.template.macroEnabled.12"
    # Keep LibreOffice for remaining formats (RTF, ODF, Visio, Project)
    - "DCV_MIMETYPE_SUPPORT_LIBREOFFICE=text/rtf,application/vnd.oasis.opendocument.text,application/vnd.oasis.opendocument.spreadsheet,application/vnd.oasis.opendocument.presentation,application/visio,application/x-visio,application/vnd.visio,application/vnd.ms-visio,application/visio.drawing,application/vsd,application/x-vsd,image/x-vsd,zz-application/zz-winassoc-vsd,application/vnd.oasis.opendocument.graphics,application/vnd.ms-project"

The DCV_ prefix is stripped at runtime, and underscores become dots. So DCV_MIMETYPE_SUPPORT_DIRECTOFFICE maps to the Spring property mimetype.support.directoffice. See Environment variables for the full naming convention.

Standalone

Edit application-security.yml in the modules/TaskConversion directory. Move the desired MS Office MIME types from libreoffice to directoffice, and keep LibreOffice for the remaining formats:

modules/TaskConversion/application-security.yml

mimetype:
  support:
    # Word, Excel, PowerPoint → DirectOffice
    directoffice: "${mime.type.msoffice.word},${mime.type.msoffice.excel},${mime.type.msoffice.powerpoint}"
    # OpenDocument formats → LibreOffice
    libreoffice: "${mime.type.libreoffice.text},${mime.type.libreoffice.sheet},${mime.type.libreoffice.presentation},${mime.type.libreoffice.graphics}"
    # Visio, Publisher, Project, RTF → MS Office (or LibreOffice if AROMS is not available)
    msoffice: "${mime.type.msoffice.publisher},${mime.type.msoffice.visio},${mime.type.msoffice.rtf},${mime.type.msoffice.project}"

In this example, Word, Excel, and PowerPoint documents go through DirectOffice. Visio, Publisher, Project, and RTF remain on MS Office/LibreOffice. OpenDocument formats stay on LibreOffice.

DirectOffice configuration reference

Property	Default	Docker env var	Description
rendition.directoffice.path	directoffice	DCV_RENDITION_DIRECTOFFICE_PATH	Path to the DirectOffice executable
soffice.conversion.timeout	120	DCV_SOFFICE_CONVERSION_TIMEOUT	Conversion timeout in seconds (shared with LibreOffice)
mimetype.support.directoffice	"" (empty)	DCV_MIMETYPE_SUPPORT_DIRECTOFFICE	Comma-separated MIME types routed to DirectOffice

Known limitations

• Diacritics in document file names are automatically stripped before conversion (transparent to end users).
• Formats like Visio, Publisher, and Project should remain with LibreOffice or MS Office — DirectOffice does not handle them.

Microsoft Office / AROMS

AROMS (ARender Office Microsoft Service) uses a local Microsoft Office installation to convert documents. This provides the highest fidelity for complex Office files but requires a Windows server with a licensed copy of Microsoft Office.

Supported versions

Microsoft Office 2013 and later. Office 365 is supported if the server has internet access. Keep Office up to date.

Prerequisites

Required software:

• .NET Framework 4.5 (download)
• Microsoft Visual C++ Redistributable 2010 (download)
• Microsoft Visual C++ Redistributable 2008 (download)

Scripted installation: Download and unzip AromsCheck, then run runCheck.bat for automatic setup. If the scripted install succeeds, skip manual installation of the prerequisites above.

Windows system configuration

Create the following directories (required for Office to run as a service):

C:\Windows\System32\config\systemprofile\Desktop
C:\Windows\SysWOW64\config\systemprofile\Desktop

Important:

• Run the Rendition service with a local account. Ensure that account can open Microsoft Office without any pop-ups, as pop-ups block rendering.
• For Excel conversion, open Excel under the service account at least once. A default printer must be configured (for example, an XPS output printer). Without a printer, Excel cannot handle page setup during conversion.
• Do not set a forwarded remote-session printer as the default. It disconnects when the session ends, breaking conversions.

AROMS configuration

Edit aroms.properties in modules/TaskConversion/aroms2pdf:

Property	Default	Description
PDF/A	false	Generate PDF/A output.
processAutoKill	false	Kill stale MS Office processes on AROMS start.
TimeoutS	120	Maximum conversion time in seconds before abort.
AromsHost	http://localhost:8000/	URL where AROMS is exposed.
LockFields	false	Disable auto-update of variable fields (e.g., date fields).
IgnorePrintAreas	true	Ignore print areas to avoid printing empty lines.
FitSheetOnOnePage	true	Fit the spreadsheet on a single PDF page instead of splitting.

MIME type routing

ARender uses MIME type placeholders to group related formats. These are defined in the document-converter application.yaml:

document-converter application.yaml (excerpt)

mime:
  type:
    msoffice:
      word: "application/msword,application/vnd.openxmlformats-officedocument.wordprocessingml.document,..."
      excel: "application/msexcel,application/vnd.ms-excel,application/x-ms-excel,..."
      powerpoint: "application/vnd.ms-powerpoint,application/vnd.openxmlformats-officedocument.presentationml.presentation,..."
      project: "application/vnd.ms-project"
      visio: "application/visio,application/x-visio,application/vnd.visio,..."
      publisher: "application/x-mspublisher,application/vnd.ms-publisher"
      rtf: "text/rtf"
    libreoffice:
      text: "application/vnd.oasis.opendocument.text"
      sheet: "application/vnd.oasis.opendocument.spreadsheet"
      presentation: "application/vnd.oasis.opendocument.presentation"
      graphics: "application/vnd.oasis.opendocument.graphics"

The mimetype.support block then assigns groups of MIME types to a conversion backend (libreoffice, directoffice, or msoffice). Adjust these mappings to control which backend handles which formats.

Conversion priority order

When a MIME type is listed under multiple backends, the converter tries them in this order: MS Office (AROMS, Windows only) → LibreOffice → DirectOffice. To activate DirectOffice for a format, you must move that format's MIME types from libreoffice to directoffice. If the same MIME type appears under both libreoffice and directoffice, LibreOffice takes priority.

Factory routing

The app.factoriesBeanNames.genericConvertOffice property in application-security.yaml lists all MIME types handled by the office conversion factory. This is separate from the backend selection above, which determines which backend the factory uses for a given type.

modules/TaskConversion/application-security.yaml

app:
  factoriesBeanNames:
    genericConvertOffice: "${mime.type.msoffice.word},${mime.type.msoffice.rtf},${mime.type.libreoffice.text},${mime.type.msoffice.excel},${mime.type.libreoffice.sheet},${mime.type.msoffice.powerpoint},${mime.type.libreoffice.presentation},${mime.type.msoffice.visio},${mime.type.libreoffice.graphics},${mime.type.msoffice.project}"

To add or remove MIME types from office conversion, edit this list. For example, to add Publisher support, append ${mime.type.msoffice.publisher} to the list.