Transcript Creating a Video Abstract From a Webcam Input Stream

Creating a Video Abstract
From a Webcam Input Stream
Using Motion Estimation
Jonathan Schiff
Objectives
• To read images from a webcam for a specified
period of time
• To determine differences between images using
motion estimation
• To select images with a difference greater than a
user specified threshold percentage to minimize
amount of data stored
• To save these selected images in an MPEG
video file along with an index of their original
position in the input stream
Implementation
• Used Java Media Framework to process
webcam information
• Wrote algorithm to compute motion
vectors mapping similarities between
images
• Used Java Native Interface to pass
information to a public domain C++ MPEG
encoder
Analysis
• Spent too much time trying to interface with first
public domain MPEG encoder before realizing
that it would not allow me to store images in their
original time sequence
• Was finally able to modify a second encoder to
achieve the ouput MPEG video file I desired
• Not satisfied with final software as it contains
bugs and lacks a nice GUI