This exam tips covers Exam Tips - Images & Sound within Images & Sound for GCSE Computer Science. Revise Images & Sound in Memory & Storage for GCSE Computer Science with 18 exam-style questions and 16 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 10 of 11 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 10 of 11
Practice
18 questions
Recall
16 flashcards
Exam Tips - Images & Sound
Most common exam questions:
- "Calculate image file size" → Width × Height × Color Depth ÷ 8
- "Calculate sound file size" → Sample Rate × Bit Depth × Duration × Channels ÷ 8
- "What is a pixel?" → Smallest unit of a digital image (picture element)
- "What is sample rate?" → Number of samples per second (Hz)
- "Higher sample rate = ?" → Better quality but larger file
Image calculation tips:
- Always multiply: Width × Height × Color Depth
- Don't forget to divide by 8 to convert bits → bytes
- Watch out for units: KB, MB, or bytes?
- 24-bit color = True Color (most common)
Sound calculation tips:
- Four factors: Sample Rate × Bit Depth × Duration × Channels
- Stereo = ×2 channels (don't forget!)
- Duration must be in seconds
- Divide by 8 for bytes
- CD quality = 44,100 Hz, 16-bit, stereo
Common mistakes to avoid:
- Forgetting to divide by 8 (bits → bytes)
- Missing "× channels" for stereo sound
- Confusing width/height order
- Not converting duration to seconds
- Mixing up sample rate (Hz) with bit depth (bits)