Tag: opencv

OpenCV #003 Pixel Intensity and Watermarks

Digital Image Processing using OpenCV (Python & C++) Highlight: In this blog post, we will explain how to scale the pixel’s intensity and make the image brighter and/or darker. We will show how to add logos onto a given image. This is known as a watermark, and we will also show how to add it in a transparent mode. Finally, we show-off with some cool effects for beginners, such as fading in and out using…
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OpenCV #002 Read, Write and Display Video

Digital Image Processing using OpenCV (Python & C++) Highlight: In this blog post we will explain how to read, display and save videos using OpenCV. We will give a code both in Python and C++. Tutorial Overview: Reading a video (Python & C++) Displaying a video (Python & C++) Saving a video (Python & C++) 1. Reading a video Reading a video frame and displaying it, is not as difficult, as one might think. Using…
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OpenCV #001 Manipulating Image Pixels

Digital Image Processing using OpenCV (Python & C++) Highlight: In this blog post, we will give an overview of what a pixel is, how a computer understands it and how pixels can be accessed and manipulated using OpenCV. Tutorial Overview: What’s a Pixel? Coordinate System in an Image. Pixel access and manipulation in Python Pixel access and manipulation in C++ 1. What’s a Pixel? When we talk about video files, we are mainly concerned with…
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CamCal #001 Perspective Projection

Highlights: In this post we will continue an exploration of the projection modeling. The basic modeling equations will be written in the matrix form. New concepts, such as vanishing points and parallel lines in images will be explained. Tutorial Overview: Perspective imaging – matrix equations How do parallel lines in 3D world behave in the image? What is a vanishing point? 1. Perspective imaging – matrix equations Let’s start with the perspective projection model equations.…
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CamCal #000 Perspective Imaging

Perspective Imaging Highlights: In this post we’re going to talk about perspective imaging. First, there is a little bit of math that is needed for the explanations of the geometry and the configuration of the camera. Second, we will use a simplified pinhole camera model. Hence, we will not talk about focus and other “non-pinhole effects” when the rays are not in focus. When we take a photo, our 3D world is mapped into a…
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