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SNP file format

From Wikipedia, the free encyclopedia
Snapshot File
Filename extension
.snp
Internet media typeapplication/vnd.ms-access, image/x-snp
Developed byMicrosoft
Type of formatAccess report output, multi-page, precise
Container forEMF (contained pages)
Contained byCAB (compression wrapper)

The SNP file format was used by Microsoft Access to store Report Snapshots in a single file which can be viewed and printed by the Microsoft Snapshot Viewer, a Windows program available free of charge from Microsoft that allows report output to be viewed without requiring Access. Support for the format was discontinued in Access 2010 and later versions; Access reports can be exported in PDF/XPS and Excel formats viewable on many platforms.[1]

SNP files are based on the Microsoft Compound File Binary Format (CFBF),[2] which is also the basis for the Advanced Authoring Format (AAF). CFBF is a reasonably simple container format which can store multiple files, directories and so on.[3] For SNP files, Microsoft Access uses CFBF to store each page as a separate Enhanced Metafile (EMF)-like format containing all of the graphics commands required to reproduce the page.[4]

The last CFBF record in an SNP file is a 'HEADER' file, which primarily contains a DEVMODE structure.[5] Data from this structure is used to render the SNP file in Microsoft Snapshot Viewer, in conjunction with the default printer selected.

As CFBF files are not compressed, Microsoft's CAB format is used to reduce the size of the CFBF, producing a file which may be only a few kilobytes in size for each page of text and simple graphics—lines, boxes, etc.

References

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  1. ^ The Access Team (9 January 2010). "Access 2010 deprecated features and components". Microsoft 365 Blog. Retrieved 29 May 2019.
  2. ^ "Advanced Authoring Format Low-Level Container Specification" (PDF). Microsoft Structured Storage version 3 specification (PDF). Archived from the original (PDF) on 2006-05-07. Retrieved 2006-05-22.
  3. ^ "Microsoft Compound Document File Format" (PDF). OpenOffice.org CFBF description. Retrieved 2006-05-22.
  4. ^ "Is Microsoft Access Snapshot considered EMF?". MSDN Forum discussion of SNP file format. Retrieved 2008-09-27.
  5. ^ "The DEVMODE data structure". Microsoft Dev Center. 5 December 2018.