Image classification arc gis10

Image Classification in ArcGIS10

ByAshok Peddi

Introduction to image classification

• Image classification tool bar has been introduced in ArcGIS 10 with different classification techniques .

• Image classification is the process of converting multiband satellite image into single band image with different classes, defined or undefined.

• You can develop training sample and you can use the samples/ trained pixels which you have developed using other remote sensing software's as well.

• To use this tool bar you need spatial Analyst extension.

Open ArcGIS and right click on the main menu bar to enable the Image

Classification toolbar(default disabled from main menu).

You need to enable Spatial Analyst

Extension by going to customize ->

extension

Once you check “image classification "it automatically add to the ArcGIS main menu. Then add the image which you want to classify to Arc Map.

Once you add the image to Arc Map, it will be added to image

classification tool bar.

Click on iso clustered

Unsupervised Classification

Use these button to

add delete the images

and mention the number

of bands then click ok

ok

If you have training

sample(Signature file/shape file)

which you want to apply the same rules with this

image, You can. Click on sample manager(1) and

then click on open file(2). You can

even create training

pixels/samples

1

2

Now iso clustered unsupervised classification is ready

Observations

• Wide variety of algorithms available including supervised, unsupervised and hybrid as well.

• Processing may take longer time than remote sensing software's.

• Not robust algorithams• Interesting thing is class probability