{"id":"image-vnd-sld","mimeType":"image/vnd.sld","name":"AutoCAD Slide","shortName":"SLD","category":"CAD \u0026 Legacy Vectors","extensions":[".sld"],"description":"The image/vnd.sld MIME type represents the AutoCAD Slide format, a legacy proprietary graphics format created by Autodesk. Introduced in the 1980s, SLD files are stripped-down, non-editable snapshots of AutoCAD drawing viewports (DWG/DXF). Designed for an era with severe hardware limitations, they allowed users to instantly load and display complex CAD drawings in automated slideshows or as custom icon menus within the AutoCAD interface, avoiding the massive computational overhead of loading full 3D geometry.","seo":{"title":"image/vnd.sld MIME Type | Developer Reference for AutoCAD Slide","description":"Complete reference for the image/vnd.sld MIME type: Autodesk AutoCAD Slide format, legacy CAD viewports, magic bytes, and file detection.","faqs":[{"question":"What is an AutoCAD Slide (.sld) file?","answer":"An AutoCAD Slide file is a legacy snapshot format created by Autodesk. It stores a simplified, non-editable visual representation of an AutoCAD viewport (lines and polygons) designed to load almost instantly on older, resource-constrained computers."},{"question":"Can I edit the CAD geometry in a .sld file?","answer":"No. Unlike standard DWG or DXF files, SLD files do not retain underlying 2D or 3D vector geometry, layers, or editable metadata. They are purely visual 'slides' intended for quick viewing and cannot be meaningfully edited back into a working CAD project."},{"question":"How do I open a .sld file today?","answer":"Modern web browsers and consumer image viewers do not support SLD files. You must use legacy versions of AutoCAD (via the VSLIDE command), specialized CAD viewers, or legacy image software like XnView or IrfanView equipped with CAD plugins to view them."}]},"index":{"compression":["Uncompressed (Vector Instructions)"],"browserSupport":{"score":1,"label":"None"},"commonUses":["Legacy AutoCAD Slideshows","AutoCAD Custom Icon Menus","Historical CAD Archival"]},"technical":{"magicBytes":{"hex":"41 75 74 6F 43 41 44 20 53 6C 69 64 65 0D 0A 1A 00","ascii":"AutoCAD Slide\\r\\n\\x1a\\x00"},"container":"AutoCAD Slide Container","compressionAlgorithm":["None"],"colorDepth":["8-bit (AutoCAD Indexed Color)"],"transparency":false,"animation":false,"metadata":{"exif":false,"xmp":false,"iccProfile":false},"alphaChannel":false,"progressiveLoading":false,"hdrSupport":false},"history":{"developer":"Autodesk, Inc.","released":"1980s","specification":"Proprietary (Autodesk DXF Reference Appendix)"},"browserSupport":{"chrome":false,"chromeVersion":"None","firefox":false,"firefoxVersion":"None","safari":false,"safariVersion":"None","edge":false,"edgeVersion":"None","internetExplorer":false},"softwareSupport":[{"name":"Autodesk AutoCAD","logo":""},{"name":"XnView","logo":""},{"name":"IrfanView (with plugins)","logo":""}],"conversion":{"convertTo":["dxf","png","jpeg"],"convertFrom":["dwg (via AutoCAD export)","dxf (via AutoCAD export)"]},"developer":{"httpHeaders":[{"header":"Content-Type","value":"image/vnd.sld"}],"htmlAccept":"image/vnd.sld, .sld","fileDetection":["Check the first 17 bytes of the file for the magic string 'AutoCAD Slide\\r\\n\\x1a\\x00' (Hex: 41 75 74 6F 43 41 44 20 53 6C 69 64 65 0D 0A 1A 00).","Some variations of the header might exist for different AutoCAD versions, but all valid SLD files start with the ASCII text 'AutoCAD Slide'."]},"prosCons":{"pros":["Allowed for instantaneous loading of highly complex architectural and engineering blueprints on low-memory MS-DOS systems","Easy-to-parse binary structure containing simple opcodes for drawing vectors and polygons"],"cons":["Completely obsolete and heavily fragmented, largely replaced by PDF and lightweight web-based DXF viewers","Destructive 'snapshot' format irrevocably strips all useful, editable CAD geometry data from the original drawing","Zero support in web browsers or standard image processing libraries"]},"specifications":{"url":"https://www.iana.org/assignments/media-types/image/vnd.sld","rfc":"","mimeAliases":["application/x-sld","image/x-sld"]},"developerSnippets":{"python":"import magic\n# Libmagic will reliably detect the 'AutoCAD Slide' header string\nprint(magic.from_file('blueprint.sld', mime=True)) # May output 'image/vnd.sld' or 'application/octet-stream' depending on the definition file","nodejs":"const fs = require('fs');\n// Manually detecting the AutoCAD Slide magic string\nconst buffer = Buffer.alloc(13);\nconst fd = fs.openSync('blueprint.sld', 'r');\nfs.readSync(fd, buffer, 0, 13, 0);\nfs.closeSync(fd);\nconst isSLD = buffer.toString('ascii') === 'AutoCAD Slide';\nconsole.log('Is AutoCAD Slide:', isSLD);","go":"import (\n    \"bytes\"\n    \"net/http\"\n)\n// http.DetectContentType will not natively recognize this format. Use a custom prefix check:\n// isSLD := bytes.HasPrefix(buf, []byte(\"AutoCAD Slide\"))","php":"$mime = mime_content_type('blueprint.sld');\necho $mime; // Standard PHP installations often fall back to 'application/octet-stream'"},"relatedFormats":["dwg","dxf"]}