1. A Very Low Cost Video Wavelet Codec
Krasimir Kolarov
Bill Lynch
Bill Arrighi
Bob Hoover
23-Nov-18
Interval Research Corp copyright 1998

2. Interval Research Corp copyright 1998
Goals and Purpose
Research into compact representation and computation on continuous spaces
2 major tasks:
- Video Compression Applications
- Compression of Data defined on high-dimensional manifolds (3D and higher)
23-Nov-18
Interval Research Corp copyright 1998

3. Interval Research Corp Copyright 1998
Features
Very low cost real-time video encoding of NTSC composite signal from legacy sources
figure of merit is ASIC silicon area required
NTSC quality video at moderate data rates
Mbits/sec = bits/pixel
Comparable quality to MPEG-2
23-Nov-18
Interval Research Corp Copyright 1998

4. Interval Research Corp copyright 1998
WZD Video Compression
Codec Thumbnail
3-D Wavelet Transform (Taubman)
Dyadic Quantization
Various Entropy codecs
Very low cost solution in ASIC
not about the best in R-D
23-Nov-18
Interval Research Corp copyright 1998

5. Interval Research Corp copyright 1998
Total Rate (bits per pixel)
Distortion
(PSNR) 1
0.5
0.25
0.75 26 40 37 33 29
less memory
less processing
= lower cost
PSNR= 20 log (255/L2)
23-Nov-18
Interval Research Corp copyright 1998

6. Interval Research Corp copyright 1998
Set of test sequences
Laserdisk sequences - bridge, fence, staircase, dancers
Cable TV sequences - talkshow
DSS sequences - basketball, news
Camera shoots - Wayne, camcorder footage
Games - Nintendo
23-Nov-18
Interval Research Corp copyright 1998

7. Interval Research Corp copyright 1998
23-Nov-18
Interval Research Corp copyright 1998

8. Interval Research Corp copyright 1998
Generating Videos
Collect sequences on Betacam SP source
Digitize in 8 bits/color ITU601 format (done by Pacific Video Resources in SF)
Use Arriba Pro to read tapes (in Abekas format) and save in bitmap or targa format
Use Bob’s box to generate D2 composite format
Use Sierra DDR to render videos
23-Nov-18
Interval Research Corp copyright 1998

9. Video of Component Compressor (basketball sequence)
23-Nov-18
Interval Research Corp copyright 1998

10. Interval Research Corp copyright 1998
Videos of Composite Interval Code Vs. MPEG2 for 4 sequences and several bitrates
23-Nov-18
Interval Research Corp copyright 1998

11. Interval Research Corp copyright 1998
Drivers of Low Cost
Temporal transform rather than motion estimation
Simple wavelet transform - no multiplies
parallel multiplies use ASIC area
2nd order boundary filters facilitate block-by-block processing
saves RAM and RAM bandwidth
Field buffers are compressed and decompressed for temporal wavelets
saves the most RAM
23-Nov-18
Interval Research Corp copyright 1998

12. ASIC Macro Cost Projections
ASIC l = 0.35 m (1997)
DRAM: 300K bits/mm2
SRAM: 60-75K bits/mm2
GATES: 12K /mm2
1998: l = 0.25 m
parameters improve by (0.35/0.25) 2 = 1.96
COST: $0.25 /mm2
23-Nov-18
Interval Research Corp copyright 1998

13. ASIC Area Requirements
1 Mbit SRAM = 12 mm2 = $3.00
100K GATES = 8 mm2 = $2.00
Opportunities
1 Mbit DRAM = 4 mm2 = $1.00
l = 0.25 m cuts area (and cost) in half
Risks
ADC and/or DACs not included in estimates
23-Nov-18
Interval Research Corp copyright 1998

14. Interval Research Corp copyright 1998
WZD Features
Traditional transform, quantize, entropy code method
Direct compression of composite NTSC
compression also decodes chroma from carrier
Modes for S-Video and component video
Low latency - less than 6 frame times
Cheap color conversion seems possible
Low power in ASIC MHz clock
23-Nov-18
Interval Research Corp copyright 1998

15. Alternatives require auxiliary RAM chips
Analog Devices ADV601
requires auxiliary DSP
Other Wavelet
require multiplies, usually motion image codec
Motion JPEG
require multiplies, worse rate/distortion in range of interest
MPEG
requires multiplies, encoder requires motion estimation, expensive encode for good rate/distortion
23-Nov-18
Interval Research Corp copyright 1998

16. Interval Research Corp copyright 1998
2-6 Wavelets
The basic wavelet used is the TS (2-6) transform, the quadratically lifted Haar wavelet.
23-Nov-18
Interval Research Corp copyright 1998

17. Interval Research Corp copyright 1998
Edge Filters
Fields of 240x704 pixels are divided into 30x22 blocks of 8x32 pixels each
Edge filters fit a quadratic to each block boundary from both left and right - 98% fit
Therefore blocking artifacts are virtually eliminated
Memory bandwidth is greatly reduced
Data handling is vastly simplified
Only adds and shifts required
23-Nov-18
Interval Research Corp copyright 1998

18. Interval Research Corp copyright 1998
2-6 Edge filters
23-Nov-18
Interval Research Corp copyright 1998

19. 4 Field G.O.P. - Temporal Processing
Each field is temporarily compressed as a still image
each requires ~200K bits ( = 1.18 bits/px.)
All 4 fields are partially decompressed in parallel lockstep
temporal linear filters are applied with serial-by-bit arithmetic
result is recompressed
23-Nov-18
Interval Research Corp copyright 1998

20. Interval Research Corp copyright 1998
Component Codec
Input - targa or .bmp format
Use 2-6 wavelets for the transform part
Use zerotree tree structure for quantization and entropy coding
Do block-by-block processing
Perform intermediate compression in the time direction
23-Nov-18
Interval Research Corp copyright 1998

21. Component Wavelet Pyramid
1: LLTTLLTL (apex), 2: LLTTLLTR, 3: LLTTLRT, 4: LLTTLLB, 5: LLTTLRB
Mallat Pyramid (3x5) with 12 subbands
23-Nov-18
Interval Research Corp copyright 1998

22. Interval Research Corp copyright 1998
Component Codec vs. ADV
2-6 Wavelet Pyramid
Temporal Wavelet
Quantize
Zerotree Encode
Entropy Decode
Reverse Temporal Wavelet
2-6 Reverse Wavelet Pyramid
7-9 Wavelets
Quantize
Entropy Encode
Entropy Decode
Inverse 7-9 Wavelets
23-Nov-18
Interval Research Corp copyright 1998

23. Interval Research Corp copyright 1998
Interval WZD vs. ADV
23-Nov-18
Interval Research Corp copyright 1998

24. Quantization of the Wavelet Coefficients
Contrast Sensitivity Curves for the Human Visual System
source B. Wandell
23-Nov-18
Interval Research Corp copyright 1998

25. Interval Research Corp copyright 1998
Quantization
Quantization coefficients are powers of 2
Implemented by right shifts
Quantization shifts align coefficient bits of equal importance in the same bit positions
Facilitates progressive coding by bitplanes of decreasing importance
e.g. SPIHT coding or arithmetic coding of bitplanes
23-Nov-18
Interval Research Corp copyright 1998

26. Interval Research Corp copyright 1998
WZD Composite Codec
Input - D2 composite format (chroma 1 and chroma 2 quadrature modulated on a 3.4 MHz sub-carrier, as in NTSC input)
2-6 wavelet pyramid for transform
Quantization step (account for HVS characteristics, less bits in color)
Entropy Coder (zerotree, arithmetic)
23-Nov-18
Interval Research Corp copyright 1998

27. Interval Research Corp copyright 1998
Composite Pyramid
23-Nov-18
Interval Research Corp copyright 1998

28. Interval Research Corp copyright 1998
WZD Codec vs. MPEG2
2-6 Wavelet Pyramid
Temporal Wavelet
Quantize (1.0 bpp or 0.5 bpp)
Entropy Encode
(zerotree, arithmetic)
Entropy Decode
Reverse Temporal Wavelet
2-6 Reverse Wavelet Pyramid
DCT (Discrete Cosine Transform)
Motion Estimation
Quantize
Entropy Encode
(Huffman)
Entropy Decode
Motion Compensation
Inverse DCT
23-Nov-18
Interval Research Corp copyright 1998

29. Interval Research Corp copyright 1998
Interval WZD vs. MPEG2
23-Nov-18
Interval Research Corp copyright 1998

30. Interval Research Corp copyright 1998
Conclusions
Temporary internal compression can reduce memory, bandwidth, and processing requirements
Short Temporal Filters can compete with motion estimation
Very low cost symmetric codecs are possible
23-Nov-18
Interval Research Corp copyright 1998

31. Interval Research Corp Copyright 1998
Cost - Rate Bubbles
MPEG-2
$100
Encoder
Hardware
Cost
ADV601
$25
Motion
JPEG
IRC-WZD $5 5 10 25
Bit Rate Mb/s
23-Nov-18
Interval Research Corp Copyright 1998