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What are Pixels?


              Pixel stands for "Picture Element". It is the smallest unit of information in a digital image. These pixels are arranged
              in a 2-dimensional grid to form a complete image, video, text, or any visible thing on a digital platform.  A pixel
              can have only one color at a time. Colour of a pixel is determined by the number of bits it represents.  The more
              pixels you have, the more closely the image resembles the original.
              Resolution is basically the dimensions through which you can measure how many pixels are on a screen. Today’s
              screen displays typically offer resolution consisting of millions of pixels or megapixels. Screen resolution is
              calculated by displaying the numbers of pixels displayed vertically or with the number of pixels displayed
              horizontally. For example, a full HD screen displays a popular HD of 1080p, which means 1080 Pixels tall by
              1920 pixels wide.
              A single static image on a full HD screen displays 2 megapixels. 1080 X 1920 = 2,073,600 (2 megapixels). But full
              motion video refreshes the screen many times per second to depict motion.
              Every image that is represented in the form of pixels also describes other features like brightness and color code.
              The most common pixel format is Byte Image, where the number is stored in an 8-bit integer ranging between
              0–255, where 0 means No Color/Black and 255 represents Full Color / White.


                       Basics of Images

              An image is a visual representation of any object. The term ‘image’ means a picture that has been created or stored
              in electronic form. It can be described in terms of vector graphics or raster graphics. An image comprises of a
              rectangular array of dots known as pixel. The size of the image is specified as width*height, in the number if pixels.
              There are different types of images let us study about them in detail.


              Greyscale Images
              A grayscale image is the one in which the value of each pixel is
              single,  i.e.,  it  carries  only  intensity  information.  Also  known  as
              Black and White, it has shades of grey. RGB channels of pixels have
              the  same  value.  These  are  images  with  only  2  colors,  black  and
              white, varying from black at the weakest intensity to white at the
              strongest. A grayscale image has each pixel of size 1 byte having a
              single plane of 2D array of pixels. In grayscale images, the shades
              range starts with 0 and ends with 255, i.e., it starts with pure black
              and ends with pure white.


                                         RGB Images

                   R           B          All colored images around us are made up of 3 primary colors of Red, Green and
                                          Blue. All the colors are made by mixing the 3 basic colors of the RGB in varying
                                          intensity.  Every  colored  image  when  split  is  stored  in  the  form  of  3  different
                                          channels, R Channel, G Channel and B Channel. Each channel has a pixel value
                         G                varying from 0-255. For example, if we see the turquoise color RGB band would
                                          look like [64, 224, 208]. In a colored image a single pixel contains red, green and
                                          blue values in triplets.





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