Video - any seq of time varying images

A video signal is a series of images (called frames) that change over time. It creates the illusion of motion when these frames are shown quickly one after the other.

A still image shows a constant picture, while a video signal consists of many images that change rapidly.

Real world → 3D signal changing in time [ t ]

• f(x, y, z, t)
  • z is intensity of a pixel at xth row and yth column of frame at time, t

Applications of Digital Video:

• Astronomy: Enhancing image quality.
• Medicine: Analyzing blood flow in veins.
• Image Compression: Reducing storage requirements.
• Sports Analysis: Improving athlete performance.
• Motion Pictures: Capturing motion for special effects.
• Robotics: Object detection and manipulation.

Digital Video Sampling

• Spatial sampling
  • Frame size: Number of pixels per frame
• Temporal Sampling
  • Frame rate: Number of frames per sec
  • Most video formats use temporal sampling rate of 24 frames per sec and above

• Spatial Sampling:
  • Digitizes image pixel intensities.
  • Human Visual System (HVS) perceives images with 8-bit precision per pixel.
• Temporal Sampling:
  • Achieves continuous motion by displaying sequential frames rapidly.
  • Typical frame rates: 24+ fps (frames per second).