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Compression Techniques Applied Resolution High Frame Leo Technology :tot Compression Techniques Applied Resolution High Frame Leo Technology ,m G. Hartz, Robert E. Atexovich, Marc S. Neustadter NAS3-24564 1989 = 1 1 Uncles HIIo2 0252030 ......... r 7-- .... -- _==:===_ - _ - 7 ...... - --_--T _ _ • _ • __ .... r- _ z L NASA Contractor Report 4263 Data Compression Techniques Applied to High Resolution High Frame Rate Video Technology William G. Hartz, Robert E. Alexovich, and Marc S. Neustadter Analex Corporation Cleveland, Ohio Prepared for Lewis Research Center under Contract NAS3-24564 N/LqA National Aeronautics and Space Administration Office of Management Scientific and Technical Information Division 1989 Table of Contents UNITS imelimew•o•eJllo .....................................H • io• • • OH•eSl.0elllHOIgWHIHllliH•g•l•lJJeJ•.•.••.• JH • 5 COMPRESSION TECHNIQUES ...................................................................... 6 Introduction ................................................................................................... 6 Performance Results ................................................................................ 6 Evaluation Criteria .................................................................................. 6 Spectral Information ............................................................................... 7 Overview of Compression Technique Performance ..................................... 9 Reversible Image Compression .................................................................... 12 Run-length _rvoding ................................................................................... 13 Contour Coding ...................................................................................... 13 Huff•an Coding ...................................................................................... 14 Arithmetic Coding ................................................................................... 14 Conditional Replenishment ..................................................................... 15 Bit-plane Encoding .................................................................................. 15 Predictive Methods ....................................................................................... 17 Differential Pulse Code Modulation ....................................................... 17 Delta Modulation ..................................................................................... 21 Motion Compensation .............................................................................. 22 Block Methods ............................................................................................... 26 Vector Quantization ................................................................................ 26 Vector DPCM .......................................................................................... 28 Block Truncation Coding. ......................................................................... 28 Variable-Resolution Coding .................................................................... 29 Micro-adaptive Picture Sequencing ................................................... 30 Tree Coding ......................................................................................... 30 Human Visual System Compensation ......................................................... 33 Synthetic Highs ...................................................................................... 33 Pyramid Coding ....................................................................................... 34 Region Growing ....................................................................................... 35 Directional Decomposition ...................................................................... 36 Anisotropic Nonstationary Predictive Coding ........................................ 38 Minimum Noise Visibility Coding .......................................................... 39 Constant Area Quantization ................................................................... 40 Perceptual Space Coding ......................................................................... 42 Transform Coding ......................................................................................... 44 Karhunen-Loeve Transform .................................................................... 55 Discrete Cosine Transform ...................................................................... 57 Slant Transform ...................................................................................... 60 Hadamard Transform ............................................................................. 62 Haar Transform ...................................................................................... 65 Hybrid Techniques ........................................................................................ 69 Discrete Cosine TransformNecter Quantization .................................. 69 Discrete Cosine Transform/MotionCompensation ................................ 70 HIGH SPEED IMPLEMENTATIONS OF VDC ALGORITHMS .................... 73 ±ii PRECEDING PAGE BLANK NOT FILMED USER REQUIREMENTS CASE STLrDIES .....................................................77 Background ............................................................................................. ...... 77 Experiment #102 - SolidSurface Combustion ............................................79 Experiment #228 - Bubble-in-LiquidMass Transport Phenomena ...........82 Experiment #230 Nucleate Pool Boiling ....................................................85 INTEGRATION OF VDC INTO HHVT SYSTEM ............................................87 ElectronicImplementations .........................................................................89 OpticalImplementations ..............................................................................92 CONCLUSIONS ................................................................................................. 94 RECOMMENDATIONS FOR FURTHER STUDY ..........................................95 BIBLIOGRAPHY .... ......................................................................................... .. 96 APPENDIX 1: BIBLIOGRAPHY DATABASE ................................................ 114 APPENDIX 2: COMPRESSION PROGRAM ................................................... 119 iv SLrMMARY This report details an investigation of video data compression applied to microgravity space experiments using High Resolution High Frame Rate Video Technology (HHVT). An extensive survey of methods of video data compression, described in the open literature, was conducted. The survey examines compression methods employing digital computing. The results of the survey are presented. They include a description of each method and an assessment of image degradation and video data parameters. An assessment is made of present and near term future technology for implementation of video data compression in a high speed imaging system. Results of the assessment are discussed and summarized in a tabular listing of implementation status. The results of a study of a baseline HHVT video system, and approaches for implementation of video data compression, are presented. Case studies of three microgravity experiments are presented and specific compression techniques and implementations are recommended. The results of the investigation conclude that video data compression approaches for microgravity space experiments are experiment peculiar in requirements and no one single approach is universally optimum. It is shown, for the experiments studied, that data compression required is separable into two approaches: the first to limit data rates for storage, and the second to reduce data rates for transmission. For high resolution and/or high frame rate experiment requirements and real time compression, hardware implementations are currently limited, by technology, to methods that can be implemented using parallel processing and simple compression algorithms. Although theoretically attractive, no approach could be identified for focal plane processing alone, that could be implemented with state of the art hardware. 1 ACRONYMS A AC Alternating Current, the remaining coefficients in a image transform A/D Analog to Digital conversion ASIC Application Specific Integrated Circuit A-VQ Address-Vector Quantization B BTC Block Truncation Coding C CAQ Constant Area Quantization CCIR Consultative Committee, International Radio CCD Charge Coupled Device CID Charge Injection Device CMOS Complementary Metal Oxide Semiconductor CR Conditional Replenishment or Compression Ratio D D/A Digital to Analog conversion DC Direct Current, refers to the average pixel value in a transform DCT Discrete Cosine Transform DCT/DPCM Discrete Cosine Transform/Differential Pulse Code Modulation DCT/MC Discrete Cosine Transform/Motion Compensation DFT Discrete Fourier Transform DM Delta Modulation DPCM Differential Pulse Code Modulation DSP Digital Signal Processing G GaAs Gallium Arsenide, a high speed semiconductor device GSP Graphics System Processor H HDTV High Definition Television HHVT High Resolution, High Frame Rate Video Technology HVS Human Visual System 2 I IDS Intensity Dependent Spread K KLT Karhunen-Loeve Transform L LPC Linear PredictiveCoding LPF Low Pass Filter LZW Lempel-Ziv-Welch algorithm M MAPS Micro-adaptive Picture Sequencing MC Motion Compensation MC/2D-DCT Motion Compensation/Two-Dimensional Transform MNVC Minimum Noise Visibility Coding MSE Mean Square Error N NMSE Normalized Mean Square
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