Lossless JPEG (original)

From Just Solve the File Format Problem
(Difference between revisions)
Jump to: navigation, search
(Software)
(Category:JPEG (organization))
 
(3 intermediate revisions by one user not shown)
Line 8: Line 8:
 
:''See [[Lossless JPEG]] for other uses of the term.''
 
:''See [[Lossless JPEG]] for other uses of the term.''
  
The original '''lossless JPEG''' (sometimes called '''lossless JPEG-1''') refers to the original [[JPEG]] format when used with lossless compression, instead of the usual lossy compression. It is a standard type of JPEG file, defined in the original JPEG standard (ITU-T Rec. T.81). Few applications support it, though it has found some use in the medical industry, such as in [[DICOM]] files. Note that this format is distinct from [[JPEG-LS]].
+
The original '''lossless JPEG''' (sometimes called '''lossless JPEG-1''') refers to the original [[JPEG]] format when used with lossless compression, instead of the usual lossy compression. It is a standard type of JPEG file, defined in the original JPEG standard (ITU-T Rec. T.81). Though few applications support it, it has found some use in the medical industry (see [[DICOM]]), and in some [[Cameras and Digital Image Sensors|raw camera formats]]. Note that this format is distinct from [[JPEG-LS]].
  
A lossless JPEG image may have any bit depth from 2 to 16 bits per sample.
+
A lossless JPEG image may have any bit depth from 2 to 16 bits per sample. The compression scheme uses [[Huffman coding]] or [[arithmetic coding]].
  
 
== Identification ==
 
== Identification ==
Line 24: Line 24:
 
* [http://www.dclunie.com/jpegge.html Stanford PVRG JPEG]
 
* [http://www.dclunie.com/jpegge.html Stanford PVRG JPEG]
 
** [http://www.cs.unibo.it/~roffilli/pub/JPEGv1.2.1_LINUXport.tgz Linux port] by [http://www.cs.unibo.it/~roffilli/sw.html Matteo Roffilli]
 
** [http://www.cs.unibo.it/~roffilli/pub/JPEGv1.2.1_LINUXport.tgz Linux port] by [http://www.cs.unibo.it/~roffilli/sw.html Matteo Roffilli]
 +
* [http://www.cybercom.net/~dcoffin/dcraw/ dcraw] includes a (probably incomplete) Lossless JPEG decoder
  
 
== Sample files ==
 
== Sample files ==
Line 30: Line 31:
  
 
[[Category:JPEG]]
 
[[Category:JPEG]]
 +
[[Category:JPEG (organization)]]

Latest revision as of 17:41, 16 October 2019

File Format
Name Lossless JPEG (original)
Ontology
Extension(s) .jpg, .ljpg, .ljpeg
LoCFDD fdd000334
Released 1992
See Lossless JPEG for other uses of the term.

The original lossless JPEG (sometimes called lossless JPEG-1) refers to the original JPEG format when used with lossless compression, instead of the usual lossy compression. It is a standard type of JPEG file, defined in the original JPEG standard (ITU-T Rec. T.81). Though few applications support it, it has found some use in the medical industry (see DICOM), and in some raw camera formats. Note that this format is distinct from JPEG-LS.

A lossless JPEG image may have any bit depth from 2 to 16 bits per sample. The compression scheme uses Huffman coding or arithmetic coding.

Contents

[edit] Identification

A lossless JPEG file is identified by the presence of an SOF3, SOF7, SOF11, or SOF15 segment. Refer to JPEG for a discussion of JPEG segments.

[edit] Specifications

[edit] Software

[edit] Sample files

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox