5. OpenCV Tutorial - Learn Classic Computer Vision & Face Detection (OPTIONAL)/2. What are Images.srt

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Hi and welcome to Section 2 of this course where we're going to take a look at the basics of computer

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vision and open C.v.

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So I will just briefly go over the topics we're covering in this section.

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So firstly we're going to take a look at what exactly are images and how were they formed after that

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we're going to look at how images are stored on computers.

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And then after we complete that we're actually going to get started into open C-v and do some basic

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operations such as reading writing and displaying images then performing grayscale operations then taking

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a look at the different colors spaces that we have available and also representing images in a histogram

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form and how you interpret that.

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And lastly we're going to use open C-v to draw some basic shapes and put tacks on images.

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So what exactly are images.

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Now I have a one line definition here for images which tells us that images are two dimensional representation

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of the visible light spectrum.

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So what does exactly does it mean what does two dimensional mean in this context.

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Now you may have a theory idea that an image can be a photograph can be something you see on your laptop

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screen or TV screen and that's exactly right.

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Those are all two dimensional planes.

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Weight is only an x y dimension and that x y dimension here corresponds to different pixel points on

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computer screens or in the photographs.

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Basically dots eight inch deep you may have hit that in somewhat a form printer printers perhaps and

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so know each pixel or GPI point reflects different wavelengths of light and that is where we refer to

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the visible light spectrum.

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Now the visible light spectrum is part of the electromagnetic spectrum which consists of radio waves

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all the way to gamma rays and different waves here have different wavelengths and divisible part.

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What we see visible because it's visible to eyes consist of different wavelengths and each wavelength

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corresponds to different colors all the way from red green to red blue and slightly purple.

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So no know in an image like this this is Van Gogh's Starry Night painting.

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Each point corresponds to a different color which means it reflects different wavelengths of light which

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is what we see in these images.

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So no I hope you have a hint there or at least an idea of what images are.