Sustainability of Digital Formats: Planning for Library of Congress Collections

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JFIF, JPEG File Interchange Format, Version 1.02

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name JPEG File Interchange Format (JFIF), Version 1.02

JFIF is a minimal file format that enables JPEG bitstreams to be exchanged between a wide variety of platforms and applications.  It does not include any of the advanced features (like tagged headers) found in the TIFF specification.  JFIF conforms to the interchange format syntax specified in JPEG Standard (ISO/IEC 10918-1, Annex B); its only additional requirement is the mandatory presence of the application segment APP0 marker right after the SOI (Start of Image) marker.

The specification for JFIF 1.02 was originally published in 1992, and made available publicly at In 2011, the International Telecommunication Union (ITU) published essentially the same specification as a recommendation ITU-T T.871 (05/2011). In 2013, the same version of JFIF was approved as ISO standard ISO/IEC 10918-5:2013. See History Notes below, for more detail

JFIF_1_02 has been assigned PRONOM PUID fmt/44. The earlier versions have PRONOM identifiers as follows: JFIF v. 1.00, PUID fmt/42;  JFIF v. 1.01, PUID fmt/43. The PRONOM Web page for JFIF 1.02 (consulted June 16, 2019) states that JFIF was developed prior to there being an official file format as a wrapper for JPEG encoding and thus JFIF "rapidly became a de facto standard." PRONOM also notes that "other types of compression are available through JPEG extensions, including progressive image buildup, arithmetic encoding, variable quantization, selective refinement, image tiling, and lossless compression, but these may not be supported by all JFIF readers and writers."

Production phase

May be used in initial-state picture creation; often used for middle- and final-state archiving or end-user delivery.

Relationship to other formats
    Subtype of JFIF_Family, JPEG File Interchange Format Family
    Contains JPEG, JPEG Image Encoding Family
    May contain JPEG_DCT_BL, JPEG DCT Compression Encoding, Baseline
    May contain JPEG_DCT_PRG, JPEG DCT Compression Encoding, Progressive
    May contain JPEG_EXT, JPEG Compression Encoding, Extensions
    May contain JTIP, JPEG Tiled Image Pyramid Format, not described at this website at this time
    May contain JPEG_orig_LL, JPEG Original Lossless Compression (ISO/IEC 10918)
    May contain JPEG-LS, JPEG Lossless Compression (ISO/IEC 14495)

Local use Explanation of format description terms

LC experience or existing holdings See JPEG.
LC preference See JPEG. The Library of Congress Recommended Formats Statement (RFS) includes JPEG/JFIF as a preferred format for photographs in digital form, other graphic images in digital form and 2D and 3D Computer Aided Design raster images. The RFS does not specify a version of JFIF.

Sustainability factors Explanation of format description terms

Disclosure Fully disclosed. Originally developed by Eric Hamilton of C-Cube Microsystems and disseminated by Joint Photographic Experts Group (""), the technical committee behind the ISO/IEC and ITU-T JPEG specifications. Published as an international standard in 2011 by ITU as Rec. T.871 and, in 2013, by ISO/IEC as ISO/IEC 10918-5.
    Documentation JPEG File Interchange Format, Version 1.02 (1992); formerly available at Essentially the same specification is available as ITU Recommendation T.871 (05/11) and ISO/IEC 10918-5:2013.
Adoption Very widely adopted, surpassing the use of either "raw" JPEG bitstreams or the SPIFF file format specified in ISO/IEC 10918, part 3.
    Licensing and patents None on the file format; see JPEG for patent claims on JPEG encoding.
Transparency JFIF structure is transparent but JPEG encoding may depend upon algorithms and tools to read; will require sophistication to build tools. See also JPEG.
Self-documentation Limited, but some technical metadata is provided by the application segment APP0, and some can be derived in other ways. For detail, see Action Plan Background: JFIF 1.02 (pp. 3-4 - link from Internet Archive) from the Florida Center for Library Automation (FCLA), now known as the Florida Academic Library Services Cooperative.
External dependencies None.
Technical protection considerations None.

Quality and functionality factors Explanation of format description terms

Still Image
Normal rendering Good support.
Clarity (high image resolution)


According to the SPIFF article in the Encyclopedia of Graphics File Formats, "JFIF took a shortcut by attempting to require that all JFIF images have a gamma of 1.0. That requirement has been widely ignored because many pre-existing images have other gamma values, and, as it turns out, a gamma of around 0.4 to 0.5 is technically superior." SPIFF marks its files with the gamma value.

Color maintenance Support for color space support appears to be more limited than SPIFF; thus no support for sRGB1. ICC Profile version (Specification ICC.1:2004-10, page 70) provides guidance for embedding ICC profiles in JFIF files as application data segments: "APP2 marker is used to introduce the tag . . . ICC tags are thus identified by beginning the data with a special null terminated bytes sequence 'ICC_PROFILE.'"
Support for vector graphics, including graphic effects and typography No support for vector graphics.
Functionality beyond normal rendering JFIF files (in version 1.02) can store thumbnails along with a larger image, including a means for defining thumbnails from source images with color space other than 24-bit RGB.

File type signifiers and format identifiers Explanation of format description terms

Tag Value Note
Filename extension jpg
From the File Extension Source. The extension jpg is most frequently used.
Filename extension jls
For JPEG-LS files, according to ISO/IEC 14495-1 and PRONOM (see PUID: fmt/150).
Internet Media Type image/jpeg
From the IANA Media Types registry. See also RFC 2046.
Internet Media Type image/jpg
Additional MIME types selected from a larger set found at File Extension Source.
Magic numbers Hex: FF D8 FF E0 xx xx 4A 46 49 46 00
The 0xFF 0xD8 part of the string is universal to all JPEG encoded bitstreams; the remainder of the string is wrapper specific. The ASCII rendering is from Gary Kessler's File Signatures Table.
Pronom PUID fmt/44
Wikidata Title ID Q1676669

Notes Explanation of format description terms


Paraphrased from James D. Murray and William vanRyper's Encyclopedia of Graphics File Formats (O'Reilly and Assoc, 1994, ISBN 1565920589): The JPEG bitstream stores 16-bit word values in big-endian format. JPEG data in general is stored as a stream of blocks, and each block is identified by a marker value. The first two bytes of every JPEG stream are the Start Of Image (SOI) marker values FFh D8h. In a JFIF-compliant file there is a JFIF APP0 (Application) marker, immediately following the SOI, which consists of the marker code values FFh E0h and the characters JFIF in the marker data, as described in the next section. In addition to the JFIF marker segment, there may be one or more optional JFIF extension marker segments, followed by the actual image data.


From as of March 2012 (link now via Internet Archive): "[T]he file format was created originally by Eric Hamilton, the then governor of JPEG as part of his work at C-Cube Microsystems, and was placed by them into the public domain under the name JFIF (available here in the latest version, 1.02)."

In 2011, the International Telecommunication Union published the recommendation ITU-T T.871 (05/2011), which states, "This Recommendation | International Standard is substantially based on the JFIF version 1.02 specification that was produced in 1992. The JFIF version 1.02 specification was widely and freely circulated, and became widely recognized as a de facto standard. This Recommendation | International Standard was developed primarily to formalize the JFIF version 1.02 specification."

In 2013, JFIF was approved as ISO standard ISO/IEC 10918-5:2013. Information technology -- Digital compression and coding of continuous-tone still images: JPEG File Interchange Format (JFIF). This standard states, "The identical text is published as Rec. ITU-T T.871 (05/2011)."

Format specifications Explanation of format description terms

Useful references


Books, articles, etc.

1The color space sRGB, standardized as IEC 61966-2-1, establishes an image viewing environment with a known color temperature (6500 degrees Kelvin) and gamma (2.2), thus increasing the user's ability to maintain color.

Last Updated: 11/20/2023