Data representation

Worked examples (9)

• 1Derive a character code from a known one
• 2Use the gap of 32 between the cases
• 3Convert a character to binary
• 4Represent a word as character codes
• 5Convert case using character arithmetic
• 6Sort strings by character code
• 7Explain why Unicode was developed
• 8Analyse the storage cost of Unicode
• 9Evaluate the claim that ASCII is obsolete

Model answers (9)

• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response

Worked examples (9)

• 1From colour depth to number of colours
• 2Resolution and the total number of pixels
• 3Telling the three terms apart
• 4Working backwards: colours to colour depth
• 5Reading a 24-bit pixel as three channels
• 6Why the header has to be there
• 7Two images, two different properties
• 8Choosing a colour depth for a logo
• 9Decoding a bitmap from its header and pixel data

Model answers (9)

• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response

Worked examples (9)

• 1Telling the sound terms apart
• 2From sample resolution to amplitude levels
• 3The CD audio standard, figure by figure
• 4Quantising and encoding three measurements
• 5The effect of halving the sample rate
• 6Comparing the data rate of two recordings
• 7Choosing a sample rate for ultrasonic recording
• 8Settings for a voice memo app
• 9Tracing the whole conversion, record to playback

Model answers (9)

• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response

Worked examples (9)

• 1Why a limited number of bits forces approximation
• 2Matching each symptom to its cause
• 3The effect of cutting a photograph's colour depth
• 4A tone sampled below the threshold
• 5How large is the quantisation error?
• 6Diagnosing a fault and rejecting the wrong fix
• 7Settings for a CCTV archive with a storage limit
• 8Two ways to halve a music file
• 9One limitation seen in three data types

Model answers (9)

• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — short open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response
• ✓Model answer — Edexcel 4CP0 Paper 1 style — extended open-response