Data Representation Topics
- Created by: MayField
- Created on: 09-11-17 12:53
View mindmap
- Data Representation
- Binary
- It is a language that computer understands
- 1 is on, 0 is off
- 1s and 0s decide which colour each pixel is
- Binary is Boolean, boolean is also known as logic
- 00001111 (Base 2) = 15 (Base 10)
- Base 10
- This is the normal 0 - 9 number system
- 15 (Base 10) = 000011111 (Base 2)
- Base 16 / Hexadecimal
- This is 0-9 and then A-F (10 - 15)
- The number is split into a half. 15 is 1 and 5.
- 1F (Base 16) = 00011111 (Base 2) = 31 (Base 10)
- Images
- Computers represent images using bits, pixels or objects
- The more bits, the higher the quality
- To work out bits depths, it is 2 to the power of the number of bits. 2x . For example 22 = 4
- To calculate the size of the image in pixels, you multiply the number of pixel vertically and horizontally by the amounts of bits was used.
- Size in Pixels = Width x Height
- Size in Bytes = Width x Height x Depth In Bits / 8
- Size in Bits = Width x Height x Depth In Bits
- Sound
- File Size (Bits) = Sample Rate x Sample
Resolution x Seconds
- Bytes = (Bits) / 8 | MegaBytes = (Bytes) / 1000 | KiloBytes = (MegaBytes) / 1000
- Sound waves are analogue data and can be represented in a graphical format
- Digital formats of a sound only use samples of a sound to save space
- The height of the bar is how sound is represented in binary
- Some sample sounds have more bars than others and this is down to the size of the sample rate
- Audio CDs have a sample rate of 44.1 kHz
- The higher the sample rate, the better the quality and the more storage taken up
- File Size (Bits) = Sample Rate x Sample
Resolution x Seconds
- ASCII & Unicode
- Unicode is better because it has 32 bits not 7 bits like ASCII
- This means that Unicode can represent other languages such as Japanese, which allows people to communicate
- Binary Addition
- 0 + 0 = 0 | 0 + 1 = 1 | 1 + 1 = 10 | 1 + 1 + 1 = 11
- You just add the binary numbers like normal addition but with special rules
- Binary Shift
- You can ‘move’ the decimal point with how many zeros there are
- As you move to the right, it becomes smaller, which is division.
- As you move the left, it become bigger, which is division.
- Binary
Comments
No comments have yet been made