Authoring: CD-I process

• Developing a CD-I application involves many steps.
• The two main ones are to assemble all the multimedia components and then to put together the CD-I application and disc.
• Assembling components:
  • Each media form is prepared and edited using a special editor.
  • Key media forms include graphics, audio, text, and programs.
  • Media forms are represented in a variety of format, each of which supports different operations and has different space and processing requirements. Thus text can be repesented as an ASCII string or as a bitmap of a page image.
  • CD-I graphics must be compact, and so uses RGB with 5 bits/pixel for each color; or a small Color Look Up Table, or DYUV encoding for natural images.
  • CD-I audio uses ADPCM compression
  • CD-I systems run the CD-RTOS operating system and allow fine control of real-time programs.
• Preparing application and disc:
  • CD-I application authors must develop a score that gives the sequencing and interaction.
  • Direct testing can take place with CD-I hardware playing from a hard drive, but the timing will be better than from a CD-I disc.
  • Hence, an emulator allows a fast disk to look like a slow CD-I system, by adding in delays. This helps with testing.
  • An image of a CD-I disk must be prepared by running special programs, which, for example, will interleave streams for faster play-back.
  • A master disk results from the pre-mastering process, and then many copies can be produced from the resulting stampers.