Perceptual Compression and Eye-tracking Lab
Department of Computer Science,
http://medianet.kent.edu
Perceptual Media Compression for Multiple Viewers with Feedback Delay
Oleg
Komogortsev, Javed I. Khan
Perceptual Compression and Eye-tracking
Lab
Department of
Last Revised
Human eyes have limited
perception capabilities. Only 2 degrees of our 180 degree vision field provide
the highest quality of perception. Due to this fact the idea of perceptual attention
focus emerged to allow a visual content to be changed in a way that only part
of the visual field where a human attention is directed to is encoded with a high
quality. The image quality in the periphery can be reduced without a viewer
noticing it. This compression approach allows a significant decrease in bit-rate
for a video stream, and in the case of the 3D stream rendering, it decreases
the computational burden. A number of
previous researchers have investigated the topic of real-time perceptual attention
focus but only for a single viewer. In this paper we investigate a dynamically
changing multi-viewer scenario. In this type of scenario a number of people are
watching the same visual content at the same time. Each person is using eye-tracking
equipment. The visual content (video, 3D stream) is sent through a network with
a large transmission delay. The area of the perceptual attention focus is
predicted for the viewers to compensate for the delay value and identify the
area of the image which requires highest quality coding.
Keywords: Perceptual compression, visual media adaptation.
This report contains experiment clips used to test the performance of this system. The videos are MPEG-2 ISO 13818-2 streams. We recommend using MPlayer found at www.mplayerhq.hu or Winamp to view these video samples.
Original Video
Samples:
One viewer is wearing eye-tracking equipments ASL 501
and watching Shamu video:
3 viewers are watching Shamu video together. Saccade Windows
are constructed. Eye-gazes are displayed:
Optimal Perceptual Attention Set (OPAF) compared to
Saccade Windows
OPAF
set has green border and USW has pink border