CS4624 Text - Ch 3
Data and File Format Standards

Key Concepts

• Standards
  • Different groups collaborate to establish market
  • Proprietary vs. open, patent vs. published
  • Corporate (Adobe), association (IMA), national, intl
• File formats
  • Multimedia content resides in file systems
  • Need special reader, writer / library (TIFF)
• Header vs. Data
  • Metadata
    • Library catalog records (MARC)
    • Dublin Core
  • Pointers
    • From header to relevant parts
    • Indexing into portions of content
• Tags
  • Attribute-value pairs
  • Variable length information
  • Required vs. optional; base vs. extension

RTF (Rich-text format)

• Character set
• Font table
• Color table
• Document formatting (margins)
• Section formatting (breaks, vertical space)
• Paragraph formatting (justification, tabs, indents, style sheets)
• General formatting (footnote, bookmark, picture)
• Character formatting (emphasis, sub/super)

TIFF (Tagged image file format)

• Tags
  • Byte order
  • Directory, directory entries
    • width, length; x/y resolution
    • bit depth, compression
  • Color map
  • Compression
  • Information: artist, software, ...
• Types of images - baseline
  • Bilevel
  • FAX
  • Gray-scale
  • Palette color
  • RGB color
• Types of images - extensions
  • Color models: CMYK, YCbCr, CIElab
  • Compression: Group 3 2D, Group 4 2D, LZW, JPEG
  • Tiled
  • Multipage

RIFF (Resource image file format)

• RIFF Concepts
  • Chunks: coded blocks of information (content)
  • Subchunk extends primary chunk
  • Lists: embed addtl info (metadata)
  • Types of content

• RIFF Formats
  • Waveform
  • Channels (mono, stereo)
  • Samples / sec, bit / sample
  • New WAVE
    • Types: Microsoft, Digispeech, Yamaha, Dolby, ...
    • ADPCM: Microsoft, DVI, Creative Labs
  • DIB (Device-independent bitmapping)
    • Tags
    • Width, height, no. planes, bits/pixel
    • Compression, color indexes, resolution
    • Palette (colors as RGB values)
      • Intensity for R, G, B for each entry
    • AVI (Audio video interleaved)
      • Frames, Interleaving: CD-ROM
      • Time scale, rate of play
      • Streams
      • Movi chunks, index chunks
      • Indeo: 2.1, 3.0, 411 YUV
    • JPEG (Joint Photographic Experts Group)
    • MJPEG
  • MIDI (Musical instrument digital interface)
    • Channel / instrument / voice
    • Polyphonic
    • Messages
      • Start, stop, continue
      • On/off, pressure, pitch change

TWAIN

• Open industry std interface for input devices
• Layers: application, protocol, acquisition
• Apps refer to generic TWAIN interface
• Device driver supports TWAIN calls
• Windows, Mac OS
• Many devices: scanners, digital cameras, frame grabbers
• Multidata formats native: TIFF, PICT, DIB