HDR File Extension
Have a problem opening a .HDR file? We collect information about file formats and can explain what HDR files are. Additionally we recommend software suitable for opening or converting such files.
Have a problem opening a .HDR file? We collect information about file formats and can explain what HDR files are. Additionally we recommend software suitable for opening or converting such files.
Derived as an abbreviation from "High Dynamic Range" (HDR), the .hdr filename extension is primarily associated with the Radiance HDR/RGBE Image File (.hdr) file type. Invented by G.Ward for the ray tracing and lighting simulation software Radiance (now, open source), the HDR image format (also known as RGBE) is specifically intended for saving high dynamic range (HDR) images. The .hdr file is an HDR raster image. By adding an extra byte per pixel in addition to the regular RGB byte values, 32 bits are used to represent one pixel in HDR (RGBE) instead of the usual 24. HDR images are used in lighting simulation, professional digital photography, and virtual reality imaging where it is necessary to capture very bright and very dark areas at the same time. Besides Radiance itself, the Radiance HDR (RGBE) image format is fully supported by many other image manipulation software tools including bitmap editors, viewers, VR simulators, and converters.
Another file type associated with the .hdr extension is the Esri BIL/BIP/BSQ Header File (.hdr) file type. BIL (Band Interleaved by Line), BIP (Band Interleaved by Pixel), and BSQ (Band Sequential) are references to the raster image formats developed by Esri and used for storing bitmap imagery in Esri's ArcGIS geodatabases. Any BIL/BIP/BSQ image is a multi-file entity, consisting of the image file (.bil/.bip/.bsq) and its header file (.hdr) as a minimum. For the binary BIL/BIP/BSQ image to be properly recognized and read, its header (.hdr) provides information about its data structure (number of rows/columns, byte order, bits per band, etc.). The name of header file (.hdr) must match the name of the image file. By itself, the .hdr file is a short ASCII text file in which keyword-value pairs are listed in sequence.
Also standing for 'header,' the .hdr extension alternatively represents the Microsoft SQL Server FILESTREAM Header File (.hdr) file type used by Microsoft SQL Server, Microsoft's commercial relational database management system (RDBMS). The FILESTREAM technology extends the database functionality with a dedicated NTFS filesystem used for storing unstructured data items such as arbitrary document files. For every FILESTREAM-enabled database, a header file ("filestream.hdr") is created in its FILESTREAM directory. For proper operation, it should not deleted or altered.