Bandwidth Issues

• 320 x 240 full color (RGB) at 30 fps = 6.9 Mbytes/sec
  • Single speed CD-ROM: 150 KBytes/sec
  • 56 K modem:  4-6 Kbytes/sec
  • Internet: 5 - 80 Kbytes/sec
  • LAN: 200 - 500 Kbytes/sec
• Therefore video must be compressed
• Intraframe compression (single frame)
  • Image quality versus amount of compression
  • JPEG 15-20 : 1 with good quality
  • Motion JPEG is about 10-15:1 with reasonable quality
• Interframe compression (between frames)
  • Defines a Keyframe every 5-15 frames and then stores only differences between intermediate frames and keyframes

Digital Video Main Page
HyperGraph Home page.