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ImageData

ImageData[image]
gives the array of pixel values in image.

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

MORE INFORMATION

ImageData[image] by default gives a 2D array whose elements are lists of values for each channel.

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.

For binary images, ImageData[image] returns integer values 0 or 1. For all other images, ImageData[image] returns real values, normally between 0 and 1.

Possible types specified by ImageData are:

	"Bit"	integer 0 or 1
	"Byte"	integer 0 through 255
	"Bit16"	integer 0 through 65535
	"Real32"	single precision real (32-bit)
	"Real"	double precision real (64-bit)

ImageData[image, Automatic] is equivalent to ImageData[image, ImageType[image]].

For images of type or , ImageData[image] always normalizes values to lie between 0 and 1. For images of type , ImageData[image] returns whatever real values are used in the image.

ImageData has the option Interleaving.

With the default setting Interleaving->True, ImageData returns a 2D array of lists of channel values.

With Interleaving->False, ImageData returns a list of 2D 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.

Basic Examples (2)

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

Construct a byte-valued image:

Extract normalized raster data:

Extract raw bytes:

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

Click for copyable input

Out[1]=

Construct a byte-valued image:

Out[1]=

Extract normalized raster data:

Out[2]=

Extract raw bytes:

Out[3]=

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

Reverse the order of rows:

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

This gives the pixel data in planar form:

Retrieve the image data in interleaved form:

Retrieve the image data in planar form:

Properties & Relations (2)

ImageData and Raster assume a different ordering of the rows:

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

Image ImageValue PixelValue ImageDimensions ImageChannels ImageType ImageQ Transpose

Image Processing

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