JPEG2000 (.jp2, .j2k)

  • Import and Export support the JP2 file format as well as the JPEG2000 features specified in Part 1 of the ISO 15444 standard.

BackgroundBackground

    MIME type: image/jp2
    JPEG2000 raster image and compression format.
    Used for photographic images.
    JPEG is an acronym for Joint Photographic Experts Group.
    Binary file format.
    Supports a variety of color resolutions and opacity.
    Uses lossy or lossless compression based on wavelet transforms.
    Can store images as an array of rectangular tiles that are encoded separately.

Import and ExportImport and Export

  • Import["file.jp2"] imports a JPEG2000 file as an image.
  • Export["file.jp2",expr] exports an image, graphics, or any other expression as a raster image to JPEG2000.
  • When exporting Wolfram Language graphics or arbitrary expressions to JPEG2000, the resulting image has the same raster size as its displayed form.
  • Image objects are by default exported at their raster size.
  • Because JPEG2000 is a raster image format, all fonts are rasterized on export.
  • Import["file.jp2",elem] imports the specified element from a JPEG2000 file.
  • Import["file.jp2",{elem,suba,subb,}] imports a subelement.
  • Import["file.jp2",{{elem1,elem2,}}] imports multiple elements.
  • The import format can be specified with Import["file", "JPEG2000"] or Import["file",{"JPEG2000",elem,}].
  • Export["file.jp2",expr,elem] creates a JPEG2000 file by treating expr as specifying element elem.
  • Export["file.jp2",{expr1,expr2,},{{elem1,elem2,}}] treats each as specifying the corresponding .
  • Export["file.jp2",expr,opt1->val1,] exports expr with the specified option elements taken to have the specified values.
  • Export["file.jp2",{elem1->expr1,elem2->expr2,},"Rules"] uses rules to specify the elements to be exported.
  • See the reference pages for full general information on Import and Export.
  • ImportString and ExportString support the JPEG2000 format.

Notebook InterfaceNotebook Interface

  • In the notebook front end, Insert Picture and the Open menu allow import of a JPEG2000 file into a cell.
  • Save Selection As exports the selected part of a notebook as a JPEG2000 file.

ElementsElements

  • General Import elements:
  • "Elements"list of elements and options available in this file
    "Rules"full list of rules for each element and option
    "Options"list of rules for options, properties, and settings
  • Data representation elements:
  • "Data"array of color values
    "Graphics"Graphics object
    "Image"raster image, given as an Image object
    "GrayLevels"array of normalized gray-level values
    "RGBColorArray"array of RGBColor objects
  • Import and Export by default use the element for JPEG2000 files.
  • Import["file.jp2","Data"] gives an array of color values taken to be encoded using the color model specified by the option.
  • The following can be used to select or specify individual image tiles:
  • "Tiles",mthe m^(th) row of tiles
    "Tiles",m,nthe n^(th) tile in row m
    "Tiles",m,n,elemelement elem of the n^(th) tile in row m
  • Advanced Import elements:
  • "BitDepth"bit resolution used for each color channel in the file
    "ImageSize"raster dimensions

OptionsOptions

  • General option:
  • ImageSizeAutomaticoverall image size
  • Import and Export option:
  • "ImageTopOrientation"Toporientation of the image as stored in the file
  • Export options:
  • "BitDepth"8bit resolution used for each color channel
    "CompressionLevel"Automaticsets the compression parameter of the image-encoding algorithm
    "ImageTopOrientation"Toporientation of the exported image
    "TileSize"Automaticpixel dimensions of image tiles
  • Allowed settings for are integers in the range from 1 to 31.
  • Possible values of range from 0 to 1, with larger values corresponding to smaller file sizes.
  • For lossy compression methods, a higher compression level corresponds to a lower quality encoding.
  • specifies the default size of the image tiles in a JPEG2000 file, and is normally set to a value of the form . The tiles in the bottom row and the rightmost column may be smaller than the default size.
  • Detailed properties and settings:
  • "ColorSpace"Automaticcolor space of the image
    "ImageEncoding""JPEG2000"compression method used in the file
    "TileDimensions"{1,1}dimensions of the tiling array
  • Import and Export support JPEG2000 alpha channels in gray-level and RGB images.
  • Possible settings for :
  • "JPEG2000"standard lossy JPEG2000 encoding
    "Lossless"lossless variant of the JPEG2000 compression method

ExamplesExamplesopen allclose all

Basic Examples  (2)Basic Examples  (2)

This imports a JPEG2000 file as an image:

In[1]:=
Click for copyable input
Out[1]=

Export an image object to JPEG2000:

In[1]:=
Click for copyable input
Out[1]=
Introduced in 2007
(6.0)
| Updated in 2008
(7.0)