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Image Segmentation

Segment images

Image segmentation is the process of partitioning an image into parts or regions. This division into parts is often based on the characteristics of the pixels in the image. For example, one way to find regions in an image is to look for abrupt discontinuities in pixel values, which typically indicate edges. These edges can define regions. Other methods divide the image into regions based on color values or texture.

Apps

Color Thresholder Threshold a color image
Image Segmenter Segment an image by refining regions

Functions

activecontour Segment image into foreground and background using active contour
imsegfmm Binary image segmentation using Fast Marching Method
imseggeodesic Segment image into two or three regions using geodesic distance-based color segmentation
gradientweight Calculate weights for image pixels based on image gradient
graydiffweight Calculate weights for image pixels based on grayscale intensity difference
grayconnected Select contiguous image region with similar gray values
graythresh Global image threshold using Otsu's method
multithresh Multilevel image thresholds using Otsu's method
otsuthresh Global histogram threshold using Otsu's method
adaptthresh Adaptive image threshold using local first-order statistics
boundarymask Find region boundaries of segmentation
superpixels 2-D superpixel oversegmentation of images
lazysnapping Segment image into foreground and background using graph-based segmentation
superpixels3 3-D superpixel oversegmentation of 3-D image
imoverlay Burn binary mask into 2-D image
label2idx Convert label matrix to cell array of linear indices

Topics

Image Segmentation Using the Color Thresholder App

This example shows how to create a binary mask image by segmenting an image using the Color Thresholder app.

Acquire Live Images in the Color Thresholder App

To color threshold an image acquired from a live webcam, use the Color Thresholder app.

Image Segmentation Using the Image Segmenter App

This example shows how to use the Image Segmenter app to segment an image.

Texture Segmentation Using Gabor Filters

This example shows how to use texture segmentation to identify regions based on their texture.

Plot Land Classification with Color Features and Superpixels

This example shows how to perform land type classification based on color features using K-means clustering and superpixels.

Segment Lungs from 3-D Chest Scan and Calculate Lung Volume

This example shows how to perform a 3-D segmentation using active contours and view the results using the Volume Viewer app.

Image Segmentation Using Point Clouds in the Color Thresholder App

This example shows how to segment an image to create a binary mask image using point cloud controls in the Color Thresholder app.

Segment Image Using Graph Cut

This example shows how to use the Graph Cut option in the Image Segmenter app to segment an image.

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