Data Compression

CS6604 Data Compression Course Materials

Syllabus

The course syllabus is current as of January 7, 2007.

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Resources

Sayood Textbook Resources
The Canterbury Corpus with standard text datasets
Sample Arithmetic Encoder/Decoder
ISO/IEC JBIG2 Standard Draft FCD14492 (1999)
ISO/IEC JPEG 10918-1 (1993)
ISO/IEC JPEG-LS Standard Draft FCD14495 (1997)
Assorted Line Drawings - in tiff Group 4 format
Assorted Text Images - in tiff Group 4 format
Sample text, about 200Mb in 1012 files.
CCITT FAX Test Images - .pbm files (binary format available though the man pages on a UNIX system). Compression ratios reported for the aggregate of 8 test images are:
- CCITT G4 - 15.5:1
- JBIG - 18.2:1
- Q-Coder - 19.0:1 (Penebaker, et. al, IBM J. Res. Dev. (32) 6, November 1988)
- 2-level coding - 21.4:1 (Witten, et al, Proc. IEEE (82) 6, 878-888, June 1994)
- TIC - 21.6:1 (Witten, et al, Proc. IEEE (82) 6, 878-888, June 1994)
lena.gif and lena.bin 512 × 512
baboon.gif and baboon.bin 512 × 512
garden.jpg and garden-red.bin, garden-green.bin, garden-blue.bin, 600 × 400
hboat.jpg and hboat-red.bin, hboat-green.bin, hboat-blue.bin, 600 × 400
hill.jpg and hill-red.bin, hill-green.bin, hill-blue.bin, 408 × 480
island.jpg and island-red.bin, island-green.bin, island-blue.bin, 640 × 476
window.jpg and window-red.bin, window-green.bin, window-blue.bin, 551 × 480

Performance Measures

Mean Square Error = Average ( | x(m,n) - x'(m,n) |² )
Peak Signal to Noise Ratio = 10 log₁₀ (255² / MSE)
Maximum Error = Max ( | x(m,n) - x'(m,n) | )

PSNR is the standard perfomance measure. At high bitrates, PSNRs above 32db are considered perceptually lossless. At medium and low bitrates, the PSNR does not necessarily agree with the perceptual quality of the image.

Assignments

Assignment 1 due February 11, 2008
Assignment 2 due February 20, 2008
Assignment 3 due February 25, 2008
Assignment 4 due March 17, 2008
Assignment 5 due April 30, 2008

Projects

Semester Project due April 28, 2008