IGCSE Computer Science
Revision Slides
Cambridge IGCSE Computer Science (0478/0984)
,1 Data
Representation
, Key Revision Points
Binary + Denary ⇔ Binary Conversions
Negative Binary Numbers + Binary Shifts
Hexadecimal + Denary ⇔ Binary ⇔ Hexadecimal Conversions + Hex Uses
Pros of Hexadecimal vs Binary + Denary
Text Representation + 3 Standard Data Transmission Codes
Bitmap Images + Colour Depth, Resolution, Metadata
Vector Images
Audio Representation + Sampling Rate, Sample Resolution + MIDI
Lossy vs Lossless Compression + 3 Reasons
Lossy vs Lossless in Images and Audio + File Formats
, Binary A base-2 number system. (0-1)
Denary A base-10 number system. (0-9)
Hexadecimal A base-16 number system. (0-F)
ASCII A standard data transmission code mapping 128 alphanumeric and punctuation
characters to 7-bit binary numbers.
Extended ASCII A standard data transmission code mapping 256 alphanumeric and punctuation
characters to 8-bit binary numbers.
Unicode A standard data transmission code mapping 65,536 alphanumeric and punctuation
characters across languages to 16-bit binary numbers.
Pixel The smallest identifiable area of an image.
Resolution The size of an image measured in pixels.
Color Depth The number of bits used to represent the colours of a pixel.
Metadata Information other than image data stored within the file.
Revision Slides
Cambridge IGCSE Computer Science (0478/0984)
,1 Data
Representation
, Key Revision Points
Binary + Denary ⇔ Binary Conversions
Negative Binary Numbers + Binary Shifts
Hexadecimal + Denary ⇔ Binary ⇔ Hexadecimal Conversions + Hex Uses
Pros of Hexadecimal vs Binary + Denary
Text Representation + 3 Standard Data Transmission Codes
Bitmap Images + Colour Depth, Resolution, Metadata
Vector Images
Audio Representation + Sampling Rate, Sample Resolution + MIDI
Lossy vs Lossless Compression + 3 Reasons
Lossy vs Lossless in Images and Audio + File Formats
, Binary A base-2 number system. (0-1)
Denary A base-10 number system. (0-9)
Hexadecimal A base-16 number system. (0-F)
ASCII A standard data transmission code mapping 128 alphanumeric and punctuation
characters to 7-bit binary numbers.
Extended ASCII A standard data transmission code mapping 256 alphanumeric and punctuation
characters to 8-bit binary numbers.
Unicode A standard data transmission code mapping 65,536 alphanumeric and punctuation
characters across languages to 16-bit binary numbers.
Pixel The smallest identifiable area of an image.
Resolution The size of an image measured in pixels.
Color Depth The number of bits used to represent the colours of a pixel.
Metadata Information other than image data stored within the file.
