Thursday, 15 September 2016

Pixel

  • The word "Pixel" invented from "Picture Element".
  • A pixel is smallest portion of a digital image or graphic that can be displayed and represented on a digital display devices.
  • All raster images are made using the pixels only.

  • The size of the pixel is depend on the how you set the resolution for the display screen.
  • The number of pixels in a image is called Resolution.
  • The pixel resolution determines the quality of display, more pixels per inch of monitor screen yields better image result.
  • Each pixel stores color information for your image.
  • It will usually store it in either three components, known as RGB(Red, Green, Blue), or four components, known as CMYK(Cyan, Magenta, Yellow, Black).
  • The number of distinct colors that can be represented by a pixel depends on the number of "bits per pixel(bpp)".
  • A 1 bpp image uses 1-bit for each pixel. Each additional bit doubles the number of colors available. 
  • For Example:
    • 1 bpp, 21 = 2 colors 
    • 2 bpp, 22 = 4 colors
    • 3 bpp, 23 = 8 colors
    • n bpp, 2n colors

Calculating Megapixel:
  • A Megapixel is a million of pixels.
  • Multiplying an image pixel width by it's pixel height gives the resolution of the image.
  • Example: take 21 Megapixel
    • 5616(pixel wide) x 3744(pixel tall) =21,026,304 pixels approximately 21 million pixels (21 megapixels).
    • Large (3072 x 2304 pixels) = 7 megapixels
    • Medium (2048 x 1536 pixels) = about 3 megapixels
    • Small (640 x 480 pixels) = 0.3 megapixels.

Examples for Pixel: