Browse Prior Art Database

Video Device Detection

IP.com Disclosure Number: IPCOM000116573D
Original Publication Date: 1995-Oct-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 76K

Publishing Venue

IBM

Related People

Sugi, H: AUTHOR

Abstract

This method allows software to describe video signal channels in a flexible way. The dynamically configurable data structure contains a list of logical video signal channels. Each logical channel contains such parameters as signal direction, physical channel identification, signal type, and connector type. An example of the implementation in the personal computer is shown in Code Segment 1.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 53% of the total text.

Video Device Detection

      This method allows software to describe video signal channels
in a flexible way.  The dynamically configurable data structure
contains a list of logical video signal channels.  Each logical
channel contains such parameters as signal direction, physical
channel identification, signal type, and connector type.  An example
of the implementation in the personal computer is shown in Code
Segment 1.

      An electric device has a fixed number of physical video signal
channels.  A plug-in jack is typically used for an input or output of
television set signals, and a 15-pin D-sub connector is commonly used
for analog video graphics signals in personal computers.  On some
devices, a single channel can carry more than one type of electric
video signals.  Some devices have more than one type of physical
signal channels.  In this method, the list contains a number of types
of video signals, and allows the expression in which a physical
channel is defined for a number of logical signal channels.

      Logical channels are uniquely identified by logical channel
numbers.  Each logical channel has a unique set of direction flag,
physical channel number, signal type, and connector type.  The
direction flag can take an in or out value.  The physical channel is
predetermined a specific system hardware configuration, particularly
depending on a analog-to-digital converter or digital-to-analog
converter.  The signal type flag can represent a specific electric
interface such as a geographically unique television signal interface
or computer graphical video signal interface.  The connector type
defines mechanical characteristics of the external interface.

      In the personal computer, the initialization software builds
the above list for the hardware system that it is running on, and
stores the list in a data structure.  After boot process starts, the
operating system refers the list to know what video signal channels
are available in what ways in the system.  The operating system can
use the list for automatic configuration, power management, and
diagnostic test purposes.  In addition to the personal computers,
this methods can be used to entertainment equipment, set top boxes,
multimedia devices, and other information processing equipment.
  --------------- Code Segment 1 ----------------------------------
    typedef enum _PhysicalChannelID {
  ViD0_Y              = 0x00,
  ViD0_C              = 0x01,
  ViD1_Y              = 0x02,
  ViD1_C              = 0x03,
  ViD2_Y              = 0x04,
  ViD2_C              = 0x05,
  ViD3_Y              = 0x06,
  ViD3_C              = 0x07,
  VoR                 = 0x10,
  VoG                 = 0x11,
  VoB                 = 0x12,
  Extension           = 0xFF,         /* Reserved...