Imaging Systems Architecture
    Same image on different devices
    Common imaging model for all applications
    Common code for all applications 
Applications
    Text Editors and Formatters
    Illustration Editors
    Page Layout
    Book Layout
Same Image Different Devices
    Workstations
        Black/White or Color Monitors
        40 spi to 300 spi

    Printers
        Black/White or Color
        Different Technologies
        150 spi to 2500 spi
Range of Performance Criteria
    Workstations
        Interacitive WYSIWYG
        Soft Printer

    Printers
        Mastermaker
        Production Printer
Common Imaging Model  (HummingBirdSlide.ip)
    Device Independent
    Uniform Set of Operations 
    2D with Priority
    Graphic Arts Quality
Common code for all Devices (Imager building blocks sequence)
    Interface and Implementation (Imager.jam)
        Common Interface
        Shared Implementation Pieces
        Specialized as Needed
    Ubiquitous
    Extensible
Examples
    Printer
    Displays
    Display List
    PDL Recorder
Integration
    All Applications use common model
        No duplicated effort
        No surprises
    Encapsulate model for basic interchange
        PDL
        Augmented PDL
        Display list
Imaging Model (ClassicBird.ip)
    Color Pressed Through Mask
        Mask: Geometric Shape
        Color: Constant or Sampled
    Makes Image on Page
    New Images Overwrite Old Ones  
Overview
    Shape Specification
    Color Specification
    Imaging Operators
    Special Rendering Issues
    Impossible Compromises
    Conclusions
Masks  (Shapes.jam)
    Filled Areas
    Strokes  (LineParams.jam)
        Offset curves
        Joints, ends
        Dashed patterns (Dashed.jam)
    Sampled Mask  (BirdBits.ais)
Shape Specification  
    Segment (CurveDefs.jam)
    Trajectory (BirdShape.jam)
    Outline (BirdHoles.jam )
    Pixel Arrays (RainbowBird)
Text  (ShoreBirds.jam)
    Fonts: Masks plus Metrics (FontDef.jam)
    Show Operator  (ShowDef.jam)
    Correct
Color Types  (ClassicBird.ip)
    Constant Color
        Pixel Value
        Color Operator
        [1,0,0]  RGBOperator
    Sampled Color    (SampledColor.jam)
        Pixel Array
        Transformation
        Color Operator
Color Specification
    Color Model  (ColorDefs.jam)
        Parameters + Model
        Produces Color Operator
    Find Color
        Specified by Name
        Functional Colors
Other Imaging Operators (ClassicBirdClipped.ip)
    Clipping
        Any Shape
        Affects All Masks
    Transformations
        All Affine Transformations
        Scale, Rotate,Translate, Skew
Imager State Variables
    Get and Set Values
    Includes
        Current Position
        Transformation
        Font
        Color
        Clipper
        Correct Parameters
Basic Rendering Primitives
    Fill Algorithms (Fill.jam)
        Parity or Wrap number
        Specifying holes
    Strokes (LineParams.jam)
        Variable Widths
        Ends and Joints
        Dashes
    Sampling
        Quality
        Speed
Special Rendering Issues
    Fonts  (FontScan.ip)
        Quality Scan-conversion 
        Proprietary Algorithms
    Color
        Color Printing
        Additive vs. Subtractive
Impossible Compromises
    Performance
        Caching
        Special Case Algorithms
        "Interactive" Modes
    Resolution too Low
        Readable Fonts    (jaggy fonts)
        Effective Halftoning (quantized gray wedge)
    Lack of color
        Capture Intent  (aic4.ip)
        Functional Specification
Conclusions
    Effective basis for document preparation systems 

    Commercially Available
        Same Image on Different Printers
    Same Image on Printers and Displays
Only in R&D
    Common Code for all Applications 
Integrated Set of Applications