Data Representation

Description

GCSE Computing Mind Map on Data Representation, created by James Howe on 05/02/2016.
James Howe
Mind Map by James Howe, updated more than 1 year ago More Less
zeligho9
Created by zeligho9 about 8 years ago
James Howe
Copied by James Howe about 8 years ago
13
0

Resource summary

Data Representation
  1. Images
    1. Bitmaps
      1. Image divided into a grid of pixels
        1. Each pixel set to a number of bits, which can contain a set number of colours
          1. If the pixel contains 4 bits, it can contain up to 2^^4 number of colours (16)
            1. Increasing the size of the image increases the size of the file as there are more pixels
              1. Increasing the resolution (quality) also increases file size
        2. The width of the picture is needed in pixels as well as the number of bits assigned to each pixel
        3. Vector Images
          1. These images do not have any data pixels but they are a specific set of instructions needed to reproduce the picture
            1. Certain elements of the picture are required to make the instructions
              1. Shape
                1. Line thickness
                  1. FIll
                    1. Colour Depth
                  2. Vector images build their instructions in relation to the photo's point of origin
                    1. As the picture is only a set of instructions, resizing the photo does not affect the resolution of the picture
                      1. Therefore file size is small
                2. Metadata
                  1. Known as "data about data"
                    1. vector images need metadata
                      1. This includes
                        1. Colour depth in bits per pixel
                          1. Date of creation
                            1. Resolution (height and width in pixels)
                              1. The Author
                        2. Number systems
                          1. Binary
                            1. Base 2 counting system, where only the numbers 0 or 1 are used
                              1. Computers read data in binary
                            2. Denary
                              1. Base 10 counting system where the numbers 0 to 9 are used
                                1. Humans use denary to count
                              2. Hexadecimal
                                1. Base 16 counting system where the numbers 0 to 9 are used, and the letters A, B, C, D, E, F are used to represent the numbers 10, 11, 12 ,13 ,14 15 respectively
                              3. Units of Information
                                1. Bit
                                  1. Nybble
                                    1. Byte
                                      1. Kilobyte
                                        1. Megabyte
                                          1. Gigabyte
                                            1. Terabyte
                                              1. Petabyte
                                                1. Exabyte
                                                  1. Yottabyte
                                                    1. Zettabyte
                                2. Sound
                                  1. Sound waves are analogue, so they must be converted to digital information for computers
                                    1. This is done by sampling the wave and storing a digital representation of the sound
                                      1. Sampling frequency is how often a sound wave is sampled
                                        1. Increasing sample frequency produces a better quality of sound but increases file size
                                        2. Sample rate determines how many different tones can be represented
                                          1. High sample rate means more tones can be represented
                                    Show full summary Hide full summary

                                    Similar

                                    A level Computing Quiz
                                    Zacchaeus Snape
                                    Types and Components of Computer Systems
                                    Jess Peason
                                    Input Devices
                                    Jess Peason
                                    Output Devices
                                    Jess Peason
                                    Computing
                                    Kwame Oteng-Adusei
                                    HTTPS explained with Carrier Pigeons
                                    Shannon Anderson-Rush
                                    Statistics, Data and Area (Semester 2 Exam)
                                    meg willmington
                                    Historical Development of Computer Languages
                                    Shannon Anderson-Rush
                                    Useful String Methods
                                    Shannon Anderson-Rush
                                    Mathematics
                                    Corey Lance
                                    Chapter 7: Investigating Data
                                    Sarah L