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JPEG2000 (.jp2, .j2k)

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 Export support the JP2 file format as well as the JPEG2000 features specified in Part 1 of the ISO 15444 standard.
  • Import imports a JPEG2000 file as an image.
  • Export exports an image, graphics or any other expression as a raster image to JPEG2000.
  • When exporting Mathematica 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 imports the specified element from a JPEG2000 file.
  • Import imports multiple elements.
  • The import format can be specified with Import["file", "JPEG2000"] or Import.
  • Export creates a JPEG2000 file by treating expr as specifying element elem.
  • Export treats each as specifying the corresponding .
  • Export exports expr with the specified option elements taken to have the specified values.
  • Export uses rules to specify the elements to be exported.
  • See the reference pages for full general information on Import and Export.
  • 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.
"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["file.jp2", "Data"] gives an array of color values taken to be encoded using the color model specified by the "ColorSpace" 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
"BitDepth"bit resolution used for each color channel in the file
"ImageSize"raster dimensions
  • General option:
ImageSizeAutomaticoverall image size
"ImageTopOrientation"Toporientation of the image as stored in the file
"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
This imports a JPEG2000 file as an image:
Export an image object to JPEG2000:
Import individual tiles and combine them:
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]=
Import individual tiles and combine them:
In[1]:=
Click for copyable input
Out[1]=