1. Trends in color
imaging on the
Internet
Giordano Beretta
Hewlett-Packard Laboratories
Robert Buckley
Xerox Architecture Center
www
AIC Color 2001, Rochester, NY
2. User expectations 2
⢠Many users access the Internet in the ofďŹce on fast
workstations connected over fast links to the Internet
⢠Increasingly, private homes are equipped with fast
connections over DSL, cable modem, satellite, âŚ
⢠At home users often have fast graphics controllers for
playing realistic computer games
⢠The latest video game machines are very powerful graphic
workstations
⢠Todayâs peripherals have âphoto qualityâ color
These user experiences set very high expectations for color
imaging on the Internet
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
3. Polarization of devices 3
The nomadic workforce
⢠The new generation grew up on video games & WWW
⢠Expect concise answers immediately on multiple media
⢠The new working world is mobile and wireless
⢠a comprehensive fast ďŹber optics network provides a global backbone
⢠the âlast mileâ is wireless
⢠computers are wearable
⢠An appropriate viewing device has not yet been invented
⢠the content will be electronic
⢠the viewing conditions will be unpredictable
⢠likely, a plethora of viewing devices will be in use
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
4. Problems raised by new trend 4
⢠How do we deal with unknown viewing conditions?
⢠How can we transmit images at very low bit rates?
⢠How can we retrieve images on the Internet?
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
5. LCD display technology 5
⢠Cost falling faster than cost of CRT
⢠Mainstream also on desktop
⢠Most implementations different from CRT
⢠white point not on Planckian Locus
⢠sigmoidal tone reproduction curve
⢠greenish blue
⢠More brands with graphic arts specs
⢠Characterization only slightly more
complex than CRT
⢠can apply ICC-based CMS
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
6. Appearance mode 6
⢠CRT is darker than surroundings
⢠perceived as object in ďŹeld of view
⢠viewing conditions must be controlled
⢠color ďŹdelity is important
⢠LCD is brighter than surroundings
⢠similar to illuminator viewing condition
⢠visual system adapts to white point, memory colors
⢠Consistency principle (Evans)
⢠reproduction of relation among colors more important than absolute
colorimetry
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
7. JPEG 2000 7
⢠Adds many features that allow Internet users to interact
with the compressed data in ways not supported by JPEG
⢠Achieves acceptable image quality at very low bit rates
⢠Wavelet based
⢠Can mimic foveation of human visual system
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
8. Image compressed with JPEG 8
0.125 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
9. Image compressed with JPEG 2000 9
0.125 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
10. JPEG codestream is packetized 10
⢠First few packets are such that you can decompress and
obtain an image with more quality in the ROI (face) than
in the periphery (surround)
⢠As more packets arrive, you obtain the data to produce
better quality in the surround, so that the entire image is
rendered at the same quality
⢠User can truncate the process anywhere in between
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
11. Image compressed with JPEG 2000 11
ROI coding (face)
equivalent to 0.125 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
12. Image compressed with JPEG 2000 12
ROI coding
equivalent to 0.25 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
13. Image compressed with JPEG 2000 13
ROI coding
equivalent to 0.5 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
14. Image compressed with JPEG 2000 14
ROI coding
equivalent to 1 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
15. Image compressed with JPEG 2000 15
ROI coding
equivalent to 2 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
16. Image compressed with JPEG 2000 16
ROI coding
equivalent to 4 bpp
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
17. Algorithms for ROI 17
⢠Human vision collects low resolution overview in the
retinaâs periphery
⢠High resolution views in the fovea with each ďŹxation as
the eye jumps from ROI to ROI under top-down control
ROIs 3K bytes
3K bytes 100K bytes
L. Stark and C. Privitera, U.C. Berkeley & eFovea
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
18. Image retrieval 18
⢠Text-based image retrieval: images are annotated and a
database management system is used to perform image
retrieval on the annotation
⢠drawback 1: labor required to manually annotate the images
⢠drawback 2: imprecision in the annotation process
⢠Content-based image retrieval systems (CBIRS) overcome
these problems by indexing the images according to their
visual content, such as color, texture, etc.
A goal in CBIR research is to design representations that
correlate well with the human visual system
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
19. Rendered images 19
⢠Stock photo agency images are rendered to a normalized
intent
⢠Typical consumer images are the raw output of digital
cameras or scanners
⢠Many CBIR algorithms rely on color histograms
⢠Need to specify when images are unrendered
⢠RIMM/ROMM RGB
⢠Need algorithms to perform automatic rendering
operation
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet
20. Conclusions 20
⢠At Color â97 in Kyoto we predicted the availability of
cheap processing and fast cheap Internet
⢠compared compression in the color domain to compression in the spatial
domain; ďŹle formats
⢠Today we see a trend towards bright LCD displays and
wireless devices
⢠color consistency more important than ďŹdelity
⢠packetized low bit rate codestreams with ROI
⢠contents based image retrieval
⢠At Color â05 we will see
⢠image-capable handheld devices with wireless Internet
⢠world-wide dop-down image search & retrieval from handheld
⢠incredibly bright handheld displays based on OLED
R.R. Buckley & G.B. Beretta AIC Color 2001 Trends in color imaging on the Internet