4.5.6 Bit patterns, images and sound representation

4.5.6 Bit patterns, images and sound representation

1. Use of bit patterns to represent graphics, sound

   • Analogue vs. Digital
     • Data
     • Signal
     • Analogue to Digital Converter (ADC) operation
       • Use of ADC with analogue sensors
     • Digital to Analogue Converter (DAC) operation
       • Use of DAC to convert digital audio to analogue signal

2. Sound

   • Sampling resolution
   • MIDI (Musical Instrument Digital Interface)
     • Purpose & use of event messages
     • Advantages for representing music
   • Sound sample sizes in bytes
   • Sampling rate
   • Nyquist theorem

3. Vector graphics

   • Image representation using list of objects
   • Typical properties of objects
   • Use of vector graphic primitives to create simple vector graphic

4. Bitmapped graphics

   • Bitmaps representation
   • Resolution in pixels
   • Colour depth in pixels
   • Image size in pixels
   • Storage requirements or File size
   • Metadata

5. Data Compression

   • Purpose for compressing image & sound files
   • Text file compression
   • Lossless vs. Lossy Compression
   • Lossless compression techniques
     • RLE (Run Length Encoding
     • Dictionary-based methods

6. Vector graphics vs. bitmapped graphics

   • Advantages
   • Disadvantages
   • Appropriate uses of each approach