{"id":"image-vnd-ms-modi","mimeType":"image/vnd.ms-modi","name":"Microsoft Document Imaging","shortName":"MODI","category":"Legacy \u0026 Proprietary","extensions":[".mdi"],"description":"The image/vnd.ms-modi MIME type represents the Microsoft Document Imaging (MDI) format. Introduced with Microsoft Office XP (2001) and used through Office 2007, MDI is a proprietary, closed-source variant of the TIFF format. It was designed specifically to store scanned documents, supporting multi-page layouts, annotations, and embedded Optical Character Recognition (OCR) text generated by the Microsoft Office Document Imaging application. Microsoft officially deprecated and removed support for the format starting with Office 2010, transitioning users to TIFF and PDF.","seo":{"title":"image/vnd.ms-modi MIME Type | Developer Reference for MDI Files","description":"Complete reference for the image/vnd.ms-modi MIME type: Microsoft Document Imaging (MDI) format, its TIFF-based structure, and how to convert legacy .mdi files.","faqs":[{"question":"What is an MDI file?","answer":"An MDI (Microsoft Document Imaging) file is a proprietary document format created by legacy versions of Microsoft Office to store scanned documents, complete with multi-page support, annotations, and searchable OCR text."},{"question":"How do I open an .mdi file on Windows 10 or 11?","answer":"Modern versions of Windows and Microsoft Office no longer support MDI files natively. To open them, you must use a third-party MDI viewer, an MDI-to-TIFF conversion tool, or manually install the legacy MDI viewer from an old Office 2007 installation disk (via SharePoint Designer 2007)."},{"question":"Is an MDI file just a TIFF file?","answer":"Essentially, yes. MDI is a highly customized variant of the standard TIFF format. It uses the exact same magic bytes as a little-endian TIFF file, but includes proprietary Microsoft tags to store OCR data and annotations that standard TIFF viewers cannot parse."}]},"index":{"compression":["LZW","Proprietary MS Compression"],"browserSupport":{"score":1,"label":"None"},"commonUses":["Legacy Scanned Document Archival","Microsoft Office XP/2003/2007 Workflows","Embedded OCR Text Storage"]},"technical":{"magicBytes":{"hex":"49 49 2A 00","ascii":"II*\\x00"},"container":"TIFF Variant","compressionAlgorithm":["LZW (Modified)"],"colorDepth":["1-bit (Monochrome)","8-bit (Grayscale)","24-bit (RGB)"],"transparency":false,"animation":false,"metadata":{"exif":false,"xmp":false,"iccProfile":false},"alphaChannel":false,"progressiveLoading":false,"hdrSupport":false},"history":{"developer":"Microsoft Corporation","released":"2001","specification":"Proprietary (Closed Source)"},"browserSupport":{"chrome":false,"chromeVersion":"None","firefox":false,"firefoxVersion":"None","safari":false,"safariVersion":"None","edge":false,"edgeVersion":"None","internetExplorer":false},"softwareSupport":[{"name":"Microsoft Office Document Imaging (Legacy)","logo":""},{"name":"MDI2TIF Converter","logo":""},{"name":"Bugysoft MDI Viewer","logo":""}],"conversion":{"convertTo":["tiff","png","jpeg"],"convertFrom":[]},"developer":{"httpHeaders":[{"header":"Content-Type","value":"image/vnd.ms-modi"}],"htmlAccept":"image/vnd.ms-modi, .mdi","fileDetection":["Check the first 4 bytes for the standard TIFF little-endian magic number: 49 49 2A 00.","Because MDI shares its header with standard TIFF files, a basic magic byte sniff will falsely identify it as 'image/tiff'.","To properly identify an MDI file, you must parse the TIFF Image File Directory (IFD) and check for proprietary Microsoft tags (such as tag 34019, which indicates the presence of an MDI-specific stream)."]},"prosCons":{"pros":["Historically provided an excellent all-in-one scanned document format with built-in OCR and annotations before PDF editing became universally accessible","Tightly integrated with Microsoft Office and SharePoint workflows in the early 2000s"],"cons":["Completely proprietary and obsolete; Microsoft abandoned it in favor of standard TIFF and PDF","Causes widespread identification conflicts since its file signature is identical to a standard TIFF","Extremely difficult to open on modern operating systems without relying on third-party conversion utilities"]},"specifications":{"url":"https://en.wikipedia.org/wiki/Microsoft_Office_Document_Imaging","rfc":"","mimeAliases":["image/mdi"]},"developerSnippets":{"python":"import magic\n# Libmagic will identify MDI files as standard TIFFs because they share the identical 49 49 2A 00 header\nprint(magic.from_file('scanned_doc.mdi', mime=True)) # Outputs 'image/tiff'","nodejs":"const FileType = require('file-type');\nconst type = await FileType.fromFile('scanned_doc.mdi');\nconsole.log(type.mime); // Often outputs 'image/tiff'. You must correlate with the .mdi extension.","go":"import (\n    \"bytes\"\n    \"net/http\"\n)\n// http.DetectContentType reads the TIFF magic bytes and returns 'image/tiff'. \n// To distinguish MDI, you need a custom TIFF parser to search for MS proprietary IFD tags.","php":"$mime = mime_content_type('scanned_doc.mdi');\necho $mime; // Standard PHP environments will resolve this to 'image/tiff'"},"relatedFormats":["tiff"]}