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08 - Bitmap and Vector Images

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

  FALSE

  TRUE

 2. Vector images are made using ______________________

  coordinates and geometry.

  mathematical formulas

  All of the above are valid answers

  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.

  TRUE

  FALSE

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

  SVG

  JPEG

  PNG

  MP3

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

  it is converted into a sequence of 256 bits

  It is deleted and re-transformed into colours

  it is converted into a sequence of ASCII characters

  it is converted into a grid of pixels.

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

  colour depths

  resolutions

  bits

  pixels

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

  how many pixels are available for each colour

  None of the above

  how many bits are available in the graphics chip

   how many colours are available for each pixel

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

  4 bits (because 4 is the minimum requirement)

  1 bit

  3 bits

  2 bits

 9. A 2-bit colour depth would allow ___________________________

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

  four different values: 00, 01, 10, 11

  3 values (as the notation is 2+1)

  2 values: 01 and 11

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

  sharper

  lower

  smaller

  greater

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

  Resolution

  Vectorisation

  None of the above

  Pixality

 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

  Never

  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?

  h * w * b = 20 * 30 * 3 = 1800 bits

  20 x 30 = 600 bits

  None of the above

  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?

  4

  8

  12

  6

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

  None of the above

  2 colours

  4 colours

  Two to the power of 4, which gives 16 colours

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

  image bit

  resolution bit

  pixel

  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

  All of the above are valid answers

  filename

  file format (e.g. jpeg, svg etc)

 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

  FALSE

  TRUE

 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

  ASCII characters

  pixel manipulation

  direct CPU manipulation

  numbers

 20. Vector graphics are used in:

  All of the above are valid answers

  CAD packages

  animated movies

  image manipulation programmes such as Adobe Photoshop

 21. Image resolution is calculated using the:

  None of the above

  bits x colour depth

  no. of pixels x the length of the image

  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

  blurry image

  compressed image

  better image resolution

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

  TRUE

  FALSE

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

  128 colours

  16 colours

  256 colours

  8 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.

  TRUE

  FALSE