WOLFRAM

ImageData[image]

gives the array of pixel values in an Image or Image3D object image.

ImageData[image,"type"]

gives the array of pixel values converted to the specified type.

Details and Options

  • ImageData[image] by default gives a 2D or 3D array whose elements are lists of values for each channel. For a single-channel image, only a value and not a list of values is returned.
  • In 2D, the array generated by ImageData[image] is arranged in the same way that the image is displayed, with the first row corresponding to the top row of pixels in the image.
  • In 3D, the array generated by ImageData[image] is arranged such that the first part corresponds to the top slice, with rows running from back to front, and columns running from left to right.
  • For binary images, ImageData[image] returns integer values 0 or 1. For images of type "Byte" or "Bit16", ImageData[image] always normalizes values to lie between 0 and 1. For images of a real type, ImageData[image] returns whatever real values are used in the image.
  • Possible types specified by ImageData[image,"type"] are:
  • "Bit"integer 0 or 1
    "Byte"integer 0 through 255
    "Bit16"integer 0 through 65535
    "Real32"single-precision real (32-bit)
    "Real64"double-precision real (64-bit)
  • ImageData[image,Automatic] is equivalent to ImageData[image,ImageType[image]].
  • ImageData has the option Interleaving.
  • With the default setting Interleaving->True, ImageData returns a 2D or 3D array of lists of channel values.
  • With Interleaving->False, ImageData returns a list of 2D or 3D arrays of values for each channel.
  • Interleaving->Automatic returns in the native form used to store the image.
  • ImageData accepts a DataReversed option. With DataReversed->True, the order of the rows is reversed.

Examples

open allclose all

Basic Examples  (3)Summary of the most common use cases

Channel data for the first five pixels of the first row:

Out[1]=1

Construct a byte-valued image:

Out[1]=1

Extract normalized raster data:

Out[2]=2

Extract raw bytes:

Out[3]=3

Extract data from a 3D image:

Options  (3)Common values & functionality for each option

DataReversed  (1)

By default, data is returned from the top to the bottom:

Out[1]=1

Reverse the order of rows:

Out[2]=2

Interleaving  (2)

Data of multichannel images is by default returned in interleaved form:

Out[1]=1

This gives the pixel data in planar form:

Out[2]=2

Retrieve the image data in interleaved form:

Out[1]=1

Retrieve the image data in planar form:

Out[3]=3

Properties & Relations  (2)Properties of the function, and connections to other functions

ImageData and Raster assume a different ordering of the rows:

Out[1]=1

To visualize image data using Raster, the rows need to be reversed:

Out[1]=1
Wolfram Research (2008), ImageData, Wolfram Language function, https://reference.wolfram.com/language/ref/ImageData.html (updated 2012).
Wolfram Research (2008), ImageData, Wolfram Language function, https://reference.wolfram.com/language/ref/ImageData.html (updated 2012).

Text

Wolfram Research (2008), ImageData, Wolfram Language function, https://reference.wolfram.com/language/ref/ImageData.html (updated 2012).

Wolfram Research (2008), ImageData, Wolfram Language function, https://reference.wolfram.com/language/ref/ImageData.html (updated 2012).

CMS

Wolfram Language. 2008. "ImageData." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2012. https://reference.wolfram.com/language/ref/ImageData.html.

Wolfram Language. 2008. "ImageData." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2012. https://reference.wolfram.com/language/ref/ImageData.html.

APA

Wolfram Language. (2008). ImageData. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ImageData.html

Wolfram Language. (2008). ImageData. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ImageData.html

BibTeX

@misc{reference.wolfram_2024_imagedata, author="Wolfram Research", title="{ImageData}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/ImageData.html}", note=[Accessed: 08-January-2025 ]}

@misc{reference.wolfram_2024_imagedata, author="Wolfram Research", title="{ImageData}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/ImageData.html}", note=[Accessed: 08-January-2025 ]}

BibLaTeX

@online{reference.wolfram_2024_imagedata, organization={Wolfram Research}, title={ImageData}, year={2012}, url={https://reference.wolfram.com/language/ref/ImageData.html}, note=[Accessed: 08-January-2025 ]}

@online{reference.wolfram_2024_imagedata, organization={Wolfram Research}, title={ImageData}, year={2012}, url={https://reference.wolfram.com/language/ref/ImageData.html}, note=[Accessed: 08-January-2025 ]}