670 Raw JPEG Stream JPEG Image (Raster) Raw JPEG Stream represents JPEG bitstream sequence of digital objects. JPEG stands for Joint Photographic Experts Group, an international organization that standardized the concept of lossy compression during the late 1980s and early 1990s. It uses DCT (Discrete Cosine Transform) compression technique used for images and audio. The standard of lossy compression is able to remove some visual data invisible to human eye which averages out colour variation and reduces the file size. JPEG image consists of a sequence of segments, each beginning with a two-byte "marker", each of which begins with a 0xFF byte, followed by a byte indicating what kind of marker it is. The signature for this entry represents the first two bytes of every JPEG stream, which are the Start Of Image (SOI) marker with values of 0xFF and 0xD8 (indicating that the baseline is DCT-based) and the End of Image (EOI) marker with valued of 0xFF and 0xD9. The second signatures represents the "colour transform" field of the APP14 which is an "Adobe" segment, representing graphic files which may have been edited in Adobe applications such as Adobe Photoshop. Binary Big-endian (Motorola) 1 Digital Preservation Department / The National Archives 11 Mar 2005 08/2023 (v.113) - Photoshop JPEG signature added 0 value to offset in EOF signature as null offset is causing max-offset to be ignored. Submitted by Preservica. 15 Aug 2023 fdd000017 Library of Congress Format Description Identifier fmt/41 PUID image/jpeg MIME jpe File extension jpg File extension jpeg File extension jif File extension jfif File extension jfi File extension 69 Raw JPEG SOI marker at BOF, EOI marker at EOF 1 Absolute from BOF 0 FFD8FF 1 Absolute from EOF 0 65536 FFD9 697 Photoshop JPEG BOF: SOI marker (FF|D8), APP14 - Photoshop Segment Marker (FF|ED), segment size {2}, Photoshop identification string, in ASCII: Photoshop 3.0. EOF: EOI marker (FF|D9) with a large offset due to the amount of photoshop metadata seen after the end of image marker in sample files. 1 Absolute from BOF 0 0 FFD8FFED{2}50686F746F73686F7020332E30003842494D 1 Absolute from EOF 0 16000 FFD9 Has lower priority than 667 JPEG File Interchange Format Has lower priority than 668 JPEG File Interchange Format Has lower priority than 669 JPEG File Interchange Format Has lower priority than 671 Still Picture Interchange File Format Has lower priority than 675 Exchangeable Image File Format (Compressed) Has lower priority than 676 Exchangeable Image File Format (Compressed) Has lower priority than 751 Exchangeable Image File Format (Compressed) Has lower priority than 1444 Exchangeable Image File Format (Compressed) Has lower priority than 2330 Exchangeable Image File Format (Compressed)