08 - Bitmap and Vector Images

 1. Images are either vectors or bitmaps. Bitmap images are made out of small parts called pixels.



 2. Vector images are made using ______________________

  mathematical formulas

  All of the above are valid answers

  coordinates and geometry.

  scalable shapes such as straight lines and curves,

 3. Bitmap graphics can be scaled without losing resolution. They can be enlarged or reduced in size - but the file size will stay almost exactly the same.



 4. One of the most common vector file formats is scalable vector graphics (____). ____is an open standard for vector graphics.





 5. When a monitor or a printer displays a vector image it is rasterised -that is _____

  it is converted into a grid of pixels.

  it is converted into a sequence of ASCII characters

  It is deleted and re-transformed into colours

  it is converted into a sequence of 256 bits

 6. Bitmap images are essentially comprised of small parts called _________




  colour depths

 7. The colour depth of an image is measured in bits. The number of bits indicates ____________

  how many pixels are available for each colour

   how many colours are available for each pixel

  None of the above

  how many bits are available in the graphics chip

 8. In a black and white image, only two colours are needed. This means it has a colour depth of___________

  2 bits

  3 bits

  4 bits (because 4 is the minimum requirement)

  1 bit

 9. A 2-bit colour depth would allow ___________________________

  3 values (as the notation is 2+1)

  2 values: 01 and 11

  1 value, as 2 is the minimum number of bits required

  four different values: 00, 01, 10, 11

 10. The ____________the colour depth (bits per pixel), the more colours are available.





 11. _________________is a measure of pixel density, usually measured in dots per inch (dpi)

  None of the above




 12. When might one want to decrease the colour depth for an image

  When you want to save file space or when you only need a specific palate of colours such a mono-chrome

  When you wish to switch to a higher resolution

  When you want to increase the number of colours stored


 13. How many bits would an image be that has a size of 20 by 30 pixels, with each pixel able to display 8 colours?

  20 x 30 = 600 bits

  None of the above

  h * w * b = 20 * 30 * 3 = 1800 bits

  8 bits (the calculation is straightforward)

 14. How many bits does the colour depth have to be if we want to store 64 colours per pixel?





 15. How many colours can each pixel store if it has a colour depth of 4bits?

  Two to the power of 4, which gives 16 colours

  2 colours

  4 colours

  None of the above

 16. The smallest possible addressable area defined by a solid colour, represented as binary, in an image is a _____________

  image bit

  resolution bit


  colour bit

 17. Image files usually also contain metadata. Metadata means 'data about data' and provides information about the image. The information includes

  colour depth

  file format (e.g. jpeg, svg etc)


  All of the above are valid answers

 18. Vectors are more efficient than bitmaps at storing large areas of the same colour because they do not need to store every pixel as a bitmap does



 19. It is possible to edit SVG images using ______________ to change the size and colour variables in HTML. This is often used for graphs and infographics in HTML5


  direct CPU manipulation

  ASCII characters

  pixel manipulation

 20. Vector graphics are used in:

  CAD packages

  All of the above are valid answers

  animated movies

  image manipulation programmes such as Adobe Photoshop

 21. Image resolution is calculated using the:

  no. of pixels x the length of the image

  bits x colour depth

  None of the above

  pixel dimensions (e.g. height x width)

 22. Display resolution is the number of dots per inch (DPI). More dots per inch give a _________________

  smaller image overall

  better image resolution

  compressed image

  blurry image

 23. A pixel can be thought of as the smallest element of a digital image.



 24. Colour depth is the number of bits used for each pixel where 1 bit is black and white and 8 bits will give _______________

  16 colours

  8 colours

  128 colours

  256 colours

 25. Vector graphics can be rescaled and resized with no loss of quality. Simple shapes that can be copied to create more complex shapes.