JPEG 2000

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JPEG 2000
IconoJpeg2000.svg
File extension : .jp2, .j2k, .jpf, .jpg2, .jpx, .jpm, .mj2, .mjp2
MIME type : image / jp2, image / jpx, image / jpm, video / mj2
Developed by: Joint Photographic Experts Group
Initial release: Dec. 2000 (Core)
Type: Graphic format
Extended by: JPEG
Standard (s) : ISO / IEC 15444


JPEG 2000 (ISO standard 15444) is a graphic format for raster graphics with image compression , such as PNG or GIF . However, JPEG 2000 is based on the discrete wavelet transform (DWT). Like the well-known JPEG , it is published by the Joint Photographic Experts Group . JPEG 2000 enables both lossless and lossy compression . This format enables good compression rates for photo-like images to be achieved. The image files can contain a range of metadata , which make it easier to manage and find the images.

Advantages over JPEG

The JPEG 2000 format offers several advantages over JPEG :

  • Better compression rate for a given quality (quality defined by objective metrics or subjective tests)
  • more than 8/12 bits per color channel possible.
  • Images larger than 64,000 × 64,000 pixels possible.
  • certain image regions of interest can be compressed and decompressed in higher quality (ROI = Region of Interest )
  • Up to 256 color channels. This enables different color profiles such as RGB and CMYK in one image, as well as other ICC profiles .
  • Much more flexible than JPEG - various progression modes, images can be optimized according to various objective quality functions.
  • Space for any metadata in the Extensible Markup Language (XML format)
  • Prescribed incremental, d. H. step-by-step image construction (optional in JPEG). This means that the display can be displayed in lower quality by simply using only part of the original file without recalculations.
  • JPEG 2000 supports alpha channels to represent transparency.

Disadvantages over JPEG

  • All extensions to JPEG 2000 file formats that go beyond the pure image data stream (such as formats of metadata, color space data) are not in the public domain . Even for the image data stream, the JPEG 2000 consortium expressly does not guarantee the freedom from possible third party licensing claims.
  • JPEG 2000 is incompatible with JPEG. Only a few programs support it, mainly due to patent problems.

Levels of compression

In the case of lossy compression, the biorthogonal Daubechies 9/7 wavelet transform is used. The lossless compression uses the biorthogonal LeGall 5/3 wavelet transform .

The decompression takes place in the reverse order without rate distortion.

Spread and support

The format is mainly used in professional environments such as medical technology and digital cinema (standardized by the Digital Cinema Initiatives ). The main reason for this is probably that the predecessor JPEG is sufficient for most users and that less free coding software is available due to licensing claims. The more expensive hardware solutions (such as decoder chips in digital cameras) are also slowing down the spread for private users.

There are qualitative differences between different decoders , which are particularly noticeable at higher compression rates.

ImageMagick , GraphicsMagick or ExactImage, which are based on the JasPer library, offer a simple, free way of creating them . However, only simple compression is supported.

The OpenJPEG project and the CQJ2K library promise a more consistent implementation of the JPEG 2000 standard in free software .

The program XnView in the Windows version (1.96) supports saving without size restrictions.

For Adobe Photoshop there was an optional plug-in from version 5 up to CS3 ; from third-party providers: a free plug-in from fnord software, a free plug-in with extensive software libraries and browser plug-ins from LuraTech Europe GmbH or the free non-commercial plug-in from LEAD Technologies, Inc. Today Adobe's products support JPEG 2000.

Corel Paint Shop Pro Photo version 8 natively supports reading and writing of JPEG 2000, PhotoLine supports it, as does the versions SE Plus, Ai Studio, DC Pro Studio and HDR Studio of the scanner and image processing software SilverFast from LaserSoft Imaging .

Some widely used programs, such as Microsoft Paint , do not yet support the standard. JasPer has proven itself as a free alternative on POSIX -compatible systems.

Mozilla Firefox on macOS shows JPEG 2000. In order for Firefox to be independent in this regard, an add-on for JPEG 2000 support was written as part of the Summer of Code '07. However, this code was never included in the Firefox core. The integration of JPEG 2000 in the browser continues to be hampered by implementation and patent law problems.

JPEG 2000 is integrated into the PDF format from version 1.5.

The VivaDesigner program from version 9 supports reading JPEG 2000.

Mathematica supports reading and writing of JPEG 2000 according to ISO 15444-1.

Apple intends to end support for JPEG 2000 in Final Cut Pro X with the update to macOS 10.15 .

IrfanView can read and write JPEG 2000 with the help of a plug-in.

File format and code stream

Like JPEG-1, JPEG 2000 distinguishes between a so-called code stream and a file format. While the code stream is sufficient to decode the samples of the image, additional meta information such as the resolution and the color space of the encoded image is stored in the file format. The ISO specifies the file extension .jp2 for the file format , no file extension is provided for the code stream, since the code stream as such is not intended to be saved directly as a file. However, the endings .jpc , .j2c or .j2k are used for this.

example Pictures

Pisagrabmal2.jpg 8.8 times compressed JPEG image of a tomb in the Camposanto Monumentale in Pisa.
Pisagrabmal 66fach2.jpg The same image compressed 66 times. You can clearly see the block artifacts .
Pisagrabmal 66-fold jp2 2.jpg The same image compressed 66 times with JPEG 2000. The block artifacts are much less pronounced.
Ori-jpg-jp2.png
original JPEG JPEG 2000

Typical properties

In contrast to JPEG-1, JPEG 2000 avoids disruptive block artifacts with high compression thanks to the wavelet transformation. Instead, the images tend to have blurring artifacts and shadows in hard contrasts. JPEG 2000 is particularly suitable for large images, since the larger blocks in wavelet filters have advantages over the rather small 8 × 8 blocks of the DCT of JPEG-1. For smaller images, depending on the image content, JPEG-1 can also offer a quality advantage.

Extensions

The JPEG 2000 standard is divided into 13 sub-standards, which, starting with the basic standard ISO / IEC 15444-1 : 2000, specify various additions and extensions to other areas of application. These include, for example:

  • 15444-2: Extended coding options, such as additional color spaces, trellis quantization, an extended file format ( .jpx ) that allows animated JPEG 2000 or the superposition of several code streams to form a common image.
  • 15444-3: Motion-JPEG 2000 for coding moving images, similar to Motion-JPEG.
  • 15444-4: Specifies conformance tests and includes stress tests for decoders
  • 15444-5: Reference software, consisting of the JasPer and the JJ2000 codec.
  • 15444-6: A compound image file format that combines several coding methods in order to optimally code scanned documents with image and text components.
  • 15444-9: An image browsing protocol with which sections of very large images (e.g. from medical databases) can be viewed interactively over the Internet.
  • 15444-10: Compression of three-dimensional volume data (JP3D)
  • 15444-12: ISO-Base-Media-Format, a container format for moving pictures specified together with MPEG .

The standardization of JPEG 2000 has now been completed, but the ISO continues to maintain the standard and still corrects errors and discusses further additions.

Applications

JPEG 2000 is not yet very well represented in the home market, but there are some special applications in which it is used extensively:

  • The DICOM standard for medical data can take JPEG-2000 images.
  • The Digital Cinema Initiatives , an association of most major film studios / distributors, uses Motion JPEG 2000 as the standard for storing, distributing, and displaying 2K and 4K footage .
  • Some television broadcasters use Motion JPEG 2000 for data-reduced transmission of SD / HD film material in their networks.
  • Some large archives use JPEG 2000 for long-term archiving of their documents. The practice rules "digitization" of the German Research Foundation allow TIFF as well as lossless JPEG 2000, cite efficient compression as an advantage and refer to the Library of Congress and the British Library , which rely on JPEG 2000.
  • On the new passports of the Federal Republic of Germany, the passport photos are saved in JPEG 2000 format with an image size of 18 kB.
  • The virtual world software Second Life uses JPEG 2000 to store all graphics and textures .
  • Some exposure services use JPEG 2000 to transmit the photos.

literature

  • David S. Taubman, Michael Marcellin: JPEG2000: Image Compression Fundamentals, Standards and Practice. (=  Kluwer International Series in Engineering & Computer Science . No. 2 ). Kluwer Academic Publishers, Boston 2001, ISBN 0-7923-7519-X .
  • Paolo Buonora, Franco Liberati: A Format for Digital Preservation of Images. A Study on JPEG 2000 File Robustness. In: D-Lib Magazine . tape 14 , no. 7/8 , doi : 10.1045 / july2008-buonora .
  • Tilo Strutz: Image data compression: basics, coding, wavelets, JPEG, MPEG, H.264 . 4th, revised. and additional edition. Vieweg + Teubner in GWV Fachverlage, Wiesbaden 2009, ISBN 978-3-8348-0472-3 .

Web links

Commons : JPEG 2000  - collection of images, videos and audio files

Individual evidence

  1. MIME Type Registrations for JPEG 2000 (ISO / IEC 15444)
  2. ^ The JasPer Project Home Page .
  3. Open-source C-library for JPEG 2000 .
  4. C library for encoding and decoding JPEG 2000 of the Digital Signal Processing Laboratory at the Department of Electronic and Information Engineering (DIEI) of the University of Perugia.
  5. to be found on the CD-ROM, since CS4 removed again
  6. Because Bandwidth Is Expensive: Adding JPEG2000 support to Firefox; Ben Karel, March 23, 2007
  7. JPEG 2000 plug-in for Firefox
  8. Comment in the Mozilla Bug Tracker on JPEG 2000: Open Problems
  9. PDF Reference, Version 1.7, see Chapter 7.4.9 JPXDecode Filter, (PDF, 8.8M; 9.0 MB).
  10. New in VivaDesigner 9. (No longer available online.) In: viva.de. VIVA, formerly in the original ; accessed on August 31, 2016 .  ( Page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / viva.de  
  11. ^ Wolfram Language & System Documentation Center . Retrieved March 12, 2019.
  12. About incompatible media in Final Cut Pro X. Apple, March 21, 2019, accessed on March 27, 2019 .
  13. IrfanView plugins. Retrieved January 23, 2020 (English).
  14. DFG practical rules "Digitization". (PDF) German Research Foundation, accessed on July 13, 2016 .