ImageResize

ImageResize[image,width]

gives a resized version of image that is width pixels wide.

ImageResize[image,{size}]

gives a resized version of image with a maximum pixel width or height given by size.

ImageResize[image,{width,height}]

gives a resized version of image that has exactly the specified pixel width and height.

ImageResize[image,{width,depth,height}]

gives a resized version of a 3D image with the specified dimensions.

Details and Options

  • Image resizing changes the dimensions of an image. This is needed when enlarging an image for viewing purposes or creating thumbnails when previewing a collection of images. It is also used to conform collections of images into a common size when batch processing, training, etc.
  • ImageResize[image,w] and ImageResize[image,{s}] preserve the original aspect ratio of image.
  • Specifications for width, height and depth can be any of the following:
  • dd pixels
    {d}maximum d pixels
    Scaled[s]a multiple s of the original size
    Allpreserve the original dimension
    Automaticdetermine value from aspect ratio
    Tiny,Small,Medium,Largepredefined absolute sizes
  • ImageResize[image,w] is equivalent to ImageResize[image,{w,Automatic}].
  • ImageResize[image,{size}] is equivalent to ImageResize[image,{{size},{size}}].
  • To obtain an image with an aspect ratio r, use ImageResize[image,w{1,r}].
  • The following options can be given:
  • Padding"Reversed"padding method
    ResamplingAutomaticresampling method

Examples

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Basic Examples  (1)

Resize an image to be 100 pixels wide:

Scope  (4)

Data  (2)

Resize a grayscale image:

Resize a 3D image:

Parameters  (2)

Specify the width of the resulting image:

Resize by a factor of :

Use Automatic to explicitly preserve the aspect ratio of the image:

Resize an image to have the larger dimension no greater than 200 pixels:

Specify both width and height dimensions:

Resize in one dimension only:

Specify a named size:

Resize a 3D image:

Resize given the new width:

Resize given the new height:

Options  (5)

Padding  (3)

By default, "Reversed" padding is used:

Use constant padding:

When resampling method is set to "Nearest", all padding methods return the same result:

With constant padding, the padding value is converted to the color space of the target image:

Resampling  (2)

By default, "Nearest" resampling method is used when increasing the size of an image:

Use "Linear" resampling:

By default, "Lanczos" resampling method is used when decreasing the size of an image:

Use method "Nearest":

Applications  (3)

Create an image thumbnail:

Conform and classify a list of day and night images.

Here is an example set containing labeled images of day and night:

Calculate the average dimension of the example images:

Create the classifier:

Try this classifier on a few test images:

Get a list of images from the web and then conform them:

Conform dimensions of the list of images:

Conform while imposing an aspect ratio that averages over the images:

Properties & Relations  (3)

Use ImageResize instead of Size argument in ImageTransformation:

Thumbnail is equivalent to ImageResize using some predefined sizes:

Importing an image with given ImageSize is equivalent to resizing after Import:

Possible Issues  (2)

Downsizing with no interpolation will give poor results for thin objects:

Use first-order interpolation:

Reducing the size of an image with high-frequency content may result in a moire pattern:

Blur the image to reduce the moire effect:

Interactive Examples  (1)

Create a pan and zoom application while fixing the displayed image size:

Introduced in 2008
 (7.0)
 |
Updated in 2014
 (10.0)