Image Classification vs Pattern Recognition vs Object Detection vs Object Tracking–A Primer

It is a common question that has been asked in all Artificial Intelligence Conference or Discussion Forums. Based on my knowledge, I thought of answering some of these questions:

1.) Image Classification (also called Image Recognition): is the process of creating a thematic image where each pixel is assigned a number representing a class / tag (this also includes ‘unclassified’. In a persons image the classes can be “complexion”, “gender”, “ethnicity”, “representational names”, etc.  

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2.) Pattern Recognition (also called Object Recognition):  Identifying/recognising the things or objects in an image. This answers the query – what objects or things are depicted in this image? For example, if you are searching for farm lands in an areal image, and other objects such as tractors, sheep’s, cattle’s etc.  There are two classifiers you can familiarize for pattern recognition.  Pixel based classification and object based classification.

  • Pixel based classification: Most of the image analysis algorithms you would encounter would be based on pixel based, However, there is a major drawback for pixel based algorithms that they do not take contextual information in to consideration. Context is how these pixel/object is associated to its environment(a relationship).
  • Object based classification: To overcome this limitation of pixel based classification, we could use Object based image analysis(OBIA) to divide images in to meaningful image-objects and evaluating their characteristics in spatial, spectral and temporal aspects.

Here is how both classification will look like one vs the other:

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3.) Object Detection: is another confusing terminology, Object Recognition was able to recognize – what type of object it is? Now object detection answers the query – where is this specific object?  Object detection is based on the point of interest of any given image; for instance electronic devices such as laptop/mobile phone in picture and recognition talked about the specific information about electronic devices, like name, type and other characteristic of particular interest point.

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4.) Object Tracking: Done in motion pictures like in animated gifs or videos, we want to track how an object is moving, where is it going, or its speed. For example: vehicle tracking in a traffic camera system.Or a Realtime object or people tracking like in Object Detection figure.

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