Digital Pictures: Representation and Compression

ISBN-13: 9781468412963 / Angielski / Miękka / 2012 / 586 str.

Arun Netravali

Opis

For thousands of years mankind has been creating pictures which attempt to portray real or imagined scenes as perceived by human vision. Cave drawings, paintings and photographs are able to stimulate the visual system and conjure up thoughts of faraway places, imagined situations or pleasant sensations. The art of motion picture creation has advanced to the point where viewers often undergo intense emotional experiences. On-the- spot news coverage gives the impression of actually witnessing events as they unfold. Relatively recently, other forms of visual information have been invented which do not, in themselves, stimulate the eye. For example, vol- tage variations in an electrical signal, as in television, can represent in analogous fashion the brightness variations in a picture. In this form the visual information can be stored on magnetic tape or transmitted over long distances, and, at least for engineering purposes, it is often much more use- ful than other forms which do stimulate human vision. With the evolution of digital techniques for information processing, storage, and transmission, the need arises for digital representation of visual information, that is, the representation of images by a sequence of integer numbers (usually binary). In this form, computer processing and digital circuit techniques can be utilized which were undreamed of only a short time ago. Machine manipulation and interpretation of visual infor- mation becomes possible. Sophisticated techniques can be employed for efficient storage of images. And processing methods can be used to significantly reduce the costs of picture transmission.

Spis treści

1. Numerical Representation of Visual Information.- 1.1 Visual Information.- 1.2 Representation by a Finite Amount of Data.- 1.3 Spatial Sampling Representation.- 1.4 Raster Scan.- 1.5 Fourier-Frequency Domain.- 1.5.1 Fourier Series.- 1.5.2 Bandlimited Images—Sampling Theorem.- 1.5.3 Frequency Domain Filtering.- 1.5.4 Frequency Spectrum of the Samples Image.- 1.5.5 Frequency Spectra of Raster Scanned Images.- 1.5.6 Discrete Fourier Transform (DFT).- 1.6 Time Varying Images.- 1.7 Quantization and Binary Word Assignment—PCM.- 1.8 Color Images.- 1.8.1 Representation of Color for Human Vision.- 1.8.2 Color Coordinate Systems and Transformations.- 1.8.2a CIE System of Color Specification.- 1.8.2b Color Mixtures.- 1.8.2c Color Transformations.- 1.9 Graphics.- 1.9.1 Scanning and Resolution.- 1.9.1a Character Legibility.- 1.9.2 Amplitude Quantization.- 1.9.2a Global Threshold Selection.- 1.9.2b Local Threshold Selection.- 1.9.3 Multilevel Pictures on Two-Level Display.- 1.9.3a Ordered Dither.- 1.9.3b Error Diffusion Technique.- References.- 2. Common Picture Communication Systems.- 2.1 Monochrome Television.- 2.2 Color Television.- 2.2.1 NTSC.- 2.2.2 PAL.- 2.2.3 SECAM.- 2.2.4 Standards Conversion.- 2.2.5 Component Digitization.- 2.3 Videoconferencing.- 2.4 Videotelephone.- 2.5 High Definition Television (HDTV).- 2.6 Graphics.- 2.6.1 Facsimile Systems.- 2.7 Interactive Picture Communication Systems.- 2.8 Earth Resources Imagery.- References.- 3. Redundancy-Statistics-Models.- 3.1 Redundancy in the Sampled Data—Information Theory.- 3.1.1 Huffman Codes.- 3.1.2 Block Coding.- 3.1.3 Conditional Coding.- 3.1.4 State-Space Conditional Coding.- 3.1.5 Universal Coding.- 3.1.6 Predictive Coding.- 3.1.7 Discrete Transform Coding.- 3.1.8 Coding with Approximation—Rate Distortion Theory.- 3.2 Monochrome Luminance Statistics.- 3.2.1 First Order Statistics.- 3.2.2 Block Statistics of Single, Still Pictures.- 3.2.3 Second Order Statistics of Single, Still Pictures.- 3.2.4 Differential Signal Statistics of Single, Still Pictures.- 3.2.5 Temporal Luminance Statistics.- 3.2.6 Discrete Transform Statistics.- 3.2.7 Statistical Models and Parameters.- 3.2.7a Gaussian Model.- 3.2.7b Correlation Models.- 3.2.7c Uniform Model.- 3.2.7d Laplacian Model.- 3.2.7e Autoregressive Models.- 3.2.7f Object Based Models.- 3.3 Color Picture Statistics.- 3.4 Statistics of Graphical Signals.- 3.4.1 Nth Order Markov.- 3.4.2 Run-Length Model.- 3.4.3 Block Models.- References.- 4. Visual Psychophysics.- 4.1 Subjective Testing.- 4.1.1 Category-Judgment Methods.- 4.1.2 Comparison Methods.- 4.1.3 Waveform Testing.- 4.1.4 Kell Factor.- 4.2 The Human Eye.- 4.3 Psychophysics of Vision.- 4.3.1 Threshold Vision.- 4.3.1a Space-Domain Threshold Vision.- 4.3.1b Visual Masking.- 4.3.1c Temporal Vision.- 4.3.1d Effect of Stimulus Shape.- 4.3.1e Frequency Domain Threshold Vision.- 4.3.2 Visibility of Random Noise.- 4.4 Psychophysics of Color Vision.- 4.4.1 Perceived Color.- 4.4.2 Color Metrics.- 4.4.3 1976 CIE-L*u*v* Formula.- 4.4.4 Spatial Effects in Color Vision.- 4.4.5 Opponent-Color Theory.- 4.5 Models for Picture Quality.- 4.5.1 Space-Domain Model.- 4.5.2 Frequency Domain Model.- 4.5.3 Color Images.- References.- 5. Basic Compression Techniques.- 5.1 Pulse Code Modulation (PCM).- 5.1.1 PCM Encoding of Component Color.- 5.1.1a Color Maps.- 5.1.2 PCM Encoding of Composite Color Waveform.- 5.2 Predictive Coding.- 5.2.1 Delta Modulation.- 5.2.2 DPCM Coding.- 5.2.3 Predictors (General).- 5.2.3a Linear Predictors.- 5.2.3b Practical Intrafield Predictors.- 5.2.3c Intrafield Predictors for Composite Television.- 5.2.3d Adaptive Intrafield Predictors.- 5.2.3e Interframe Prediction.- 5.2.3f Motion Estimation.- 5.2.3g Block Matching Methods.- 5.2.3h Recursive Methods.- 5.2.3i Gain Compensation.- 5.2.3j Motion Compensation for Color Television.- 5.2.3k Effects of Transmission Errors.- 5.2.4 Quantization.- 5.2.4a Nonadaptive Quantization.- 5.2.4b Nonadaptive Quantization for Color Signals.- 5.2.4c Adaptive Quantization.- 5.2.4d Code Assignment.- 5.3 Transform Coding of Blocks of Samples.- 5.3.1 Discrete Linear Orthonormal Transforms.- 5.3.1a Discrete Fourier Transform (DFT,RDFT).- 5.3.1b Walsh-Hadamard Transform (WHT).- 5.3.1c Karhunen-Loeve Transform (KLT).- 5.3.1d Discrete Cosine Transform (DCT).- 5.3.1e Comparison of RDFT, WHT, KLT, DCT.- 5.3.1f Miscellaneous Transforms.- 5.3.2 Quantization of Transform Coefficients.- 5.3.3 Adaptive Coding of Transform Coefficients.- 5.3.4 Transform Coding of Color Pictures.- 5.3.5 Interframe or Three-Dimensional Transform Coding.- 5.4 Hybrid Transform Coding Techniques.- 5.4.1 Intraframe Hybrid Transform Coding.- 5.4.2 Interframe Hybrid Transform Coding.- 5.4.3 Interrelation Between Hybrid Transform Coding and Predictive Coding.- 5.5 Other Block Coding.- 5.5.1 Vector Quantization and Variations.- 5.5.1a Design of VQ Codebook Using Training Images.- 5.5.1b VQ Variants and Improvements.- 5.5.1c Performance of VQ Codes.- 5.5.2 Nonunitary Interpolative Transform Coding.- 5.5.3 Block Truncation Coding (BTC).- 5.6 Miscellaneous Coding Methods.- 5.6.1 Interpolative and Extrapolative Coding.- 5.6.2 Motion Adaptive Interpolation.- 5.6.3 Pyramid Coding, Subband Coding.- 5.7 Coding of Graphics.- 5.7.1 Exact Coding.- 5.7.1a Run-Length Coding.- 5.7.1b Predictive Coding.- 5.7.1c Line-to-Line Run-Length Difference Coding.- 5.7.1d Block Coding.- 5.7.2 Approximate Coding.- 5.7.3 Transmission Errors.- 5.7.4 Soft Facsimile.- 5.7.5 Coding of Line Drawings.- References.- 6. Examples of Codec Designs.- 6.1 Image Coding Method for Freeze-Frame Videoconferencing.- 6.2 45 Mbs Intrafield DPCM Codec for NTSC Color Video.- 6.3 Adaptive Predictive Interfield Coder for NTSC Color TV.- 6.4 Interfield Hybrid Transform Coder for Component Color TV.- 6.5 Decomposition of Single Images into Edges and Texture.- 6.6 Conditional Replenishment DPCM Codecs.- 6.6.1 Coding at Primary Rates for Videoconferencing.- 6.6.2 Video Coding at Sub-Primary Rates.- 6.6.3 Error Control.- 6.7 Graphic Coders.- 6.7.1 CCITT — One-Dimensional Coding Scheme.- 6.7.2 CCITT — Two-Dimensional Coding Scheme.- References.- 7. Postscript.- 7.1 Signal Sources.- 7.2 The Human Receiver.- 7.3 Waveform Encoding.- 7.4 Parameter Coding.- 7.5 Bit Rates Versus Complexity.- 7.6 Future Directions and Ultimate Limits.- 7.6.1 Waveform Encoding.- 7.6.2 Parameter Coding.- 7.6.3 Ultimate Display.- 7.7 Concluding Remarks.- References.