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Learn Fourier Transform | Image Processing with OpenCV
Computer Vision Course Outline
course content

Course Content

Computer Vision Course Outline

Computer Vision Course Outline

1. Introduction to Computer Vision
2. Image Processing with OpenCV
3. Convolutional Neural Networks

book
Fourier Transform

The Fourier Transform

The Fourier Transform (FT) is a fundamental mathematical tool used in image processing to analyze the frequency components of an image. It allows us to transform an image from the spatial domain (where pixel values are represented directly) to the frequency domain (where we analyze patterns and structures based on their frequency). This is useful for tasks like image filtering, edge detection, and noise reduction.

First, we need to convert the image to grayscale:

To compute the 2D Fourier Transform:

Here, fft2() converts the image from the spatial domain to the frequency domain, and fftshift() moves low-frequency components to the center.

To visualize the magnitude spectrum:

Since Fourier Transform outputs complex numbers, we take the absolute values (np.abs()) for a meaningful visualization.

The np.log function enhances visibility, as raw magnitude values vary greatly in scale.

Task

Swipe to start coding

Your task in this chapter is:

  • Apply Fourier Transform to sheep image;
  • Calculate a magnitude spectrum.

Solution

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Section 2. Chapter 2
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book
Fourier Transform

The Fourier Transform

The Fourier Transform (FT) is a fundamental mathematical tool used in image processing to analyze the frequency components of an image. It allows us to transform an image from the spatial domain (where pixel values are represented directly) to the frequency domain (where we analyze patterns and structures based on their frequency). This is useful for tasks like image filtering, edge detection, and noise reduction.

First, we need to convert the image to grayscale:

To compute the 2D Fourier Transform:

Here, fft2() converts the image from the spatial domain to the frequency domain, and fftshift() moves low-frequency components to the center.

To visualize the magnitude spectrum:

Since Fourier Transform outputs complex numbers, we take the absolute values (np.abs()) for a meaningful visualization.

The np.log function enhances visibility, as raw magnitude values vary greatly in scale.

Task

Swipe to start coding

Your task in this chapter is:

  • Apply Fourier Transform to sheep image;
  • Calculate a magnitude spectrum.

Solution

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Section 2. Chapter 2
Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
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