Classifications

• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
  • G09G5/00—Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators
  • G09G5/003—Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto
  • G09G5/006—Details of the interface to the display terminal
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
  • G09G2340/00—Aspects of display data processing
  • G09G2340/12—Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels
  • G09G2340/125—Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels wherein one of the images is motion video

Definitions

• the invention relates to a information presentation system as recited in the preamble of Claim 1.
• a system has been disclosed in US Patent 5,448,263.
• user interaction is effected on a touch sensitive surface, which same surface is being used for thereon projecting the application generated image.
• this system is expensive, and furthermore, the range of allowable types of input informations is restricted to those that have been defined for the touch sensitive surface. For example, no colour signals may be inputted and various rendering techniques such as hatching, underlining text and various others are virtually impossible to implement. Also, motion may be inputted only in a very limited and incremental manner.
• the inventor has recognized a growing need for a low cost-and easy-to-use system for allowing to input a broad gamut of user defined image based signalizations.
• User functionalities such as offered by a so-called overhead projector would be a boon.
• Such overhead projector allows in fact the viewing of printed paper, instant writing with a felt pen, and even small objects. In case of a computer-generated image, the instantaneous adding thereto of handwritten notes would be welcomed.
• Figure 2 a block diagram of a Mixed Mode Document Camera.
• Figure 1 shows an overview of an inventive information presentation system. It is based on computer 64 with keyboard 66 which is loaded with an application program.
• the application may be presented by memory 62, network 60, or by other means.
• the application can generate an image that is displayed on screen 76 through projection subsystem 74, that operates in front projection. However, rear projection would be feasible as well in a slightly different configuration.
• the projection subsystem is fed by image-wise mixer subsystem 68 that is fed by the computer at left.
• the system has camera 70 that captures a user image, such as one produced independently on sheet 72.
• the camera-generated image is also sent to mixer subsystem 68, so that the overall image on screen 76 is a composite or mixed one.
• FIG. 70 is a block diagram of a Mixed Mode Document Camera embodiment according to the invention.
• a VGA or similar composite output signal from the computer is received on interface 20, which has a line duration of about 32 microsecs.
• the signal inter alia comprises a horizontal sync signal on line 28 and a vertical sync signal on line 24.
• the line frequency is divided by a factor of 2 to get the line time about equal to the standard television line time of some 64 microsecs.
• Other standards would require other adaptations.
• the upper part of the arrangement mainly comprises camera module 22, that may be of a commercially available type Philips VCM 3300 as described in the brochure Monochrome Cameras & Modules published by Philips Electronics N.V. Eindhoven, The Netherlands. This module has a resolution of 768*492 pixels. Vertical sync is at 16 millisecs and horizontal at 64 microsecs. Colour modules would operate in a similar manner, which has not been described for brevity. Module 22 serves for preparing the camera image for mixing with the VGA signal.
• camera module 22 receives Horizontal and Vertical Sync signals, as well as detection signals from H/V sync detector 30. If the latter are present indeed, camera synchronization is on external, but otherwise on internal. Camera output is a conventional Color Video Blanking & Sync signal. Horizontal and Vertical Sync signals from the input interface 20 are sent to output VGA interface 32.
• Block 34 receives the CVBS signal from block 22 and the divided-by-2 Horizontal Sync for in a standard procedure precorrecting against vignetting and other causes of non-uniform image illumination.
• block 36 is an A/D converter for allowing a more convenient processing of the camera output.
• Block 38 contains a FIFO storage facility.
• processing mechanisms such as changing the relative size of the camera image, changing the image colour, black-white inverting, filtering text through a text recognition feature, converting to another computer display standard, or converting of the camera image to emulate a computer- generated image may be executed here as well, through providing an appropriate amount of processing facilities. Also, software controlled mixing of driver level images may be done here. By themselves, the necessary facilities are conventional.
• the output signals from FIFO 38 are reconverted to analog in D/A block 40 and presented to analog mixer module 44 that also comprises a fast switch for effecting changeover between the two image inputs.
• Block 44 operates under control from block 42 that contains a control circuit and a mode switch. A user may herein select between various modes that will be elucidated hereinafter.
• the composite mixed signal from block 44 is sent along line bundle 46 to output VGA interface 32, for being displayed on an appropriate projection display device.
• the above system may have the following extra features.
• the mixing may as recited be video mixing.
• a more refined embodiment may have software controlled driver level image mixing, wherein certain properties of the respective images may influence the actual mixing mechanism parameters.
• a contrast detector may be present for measuring camera contrast.
• the contrast may be enhanced for the camera image, as well as for the computer generated image.
• camera letters may be inverted before mixing to white-on-black. If the computer image is predominantly in a particular color, the camera image may be amended to not include this color.
• Various operational modes are as follows.
• a high quality text mode the computer signal is inverted as soon as the camera views dark text. This allows representing written camera text at high contrast without interfering with VGA-generated contrast.
• a second mode is graphical that adds VGA signal and camera signal together. Further, this mode allows to vary the respective intensities of the two signals.
• a preferred packaging combines the camera with the electronic circuitry necessary for effecting the present invention in a Mixed Mode Document Camera.
• the camera has Autocontrast filtering control for allowing the use of various different types of writing pens and or paper.
• Four main modes are possible: 1.
• VGA image mode blocks camera image.
• Text mode displays text in preference over the VGA image, through using the above fast switch.
• Graphical mode mixes the camera image, for example a photograph, through the VGA image.
• Camera mode blocks the VGA image and displays only camera image. Further modes are feasible, such as dividing screen area into subscreens, each thereof allowing a respective different mode.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Computer Hardware Design (AREA)
• General Physics & Mathematics (AREA)
• Theoretical Computer Science (AREA)
• Controls And Circuits For Display Device (AREA)
• Digital Computer Display Output (AREA)
• Image Processing (AREA)
• Studio Devices (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=8233769

Family Applications (1)

Country Status (4)

Family Cites Families (5)

• 1999
  • 1999-05-25 KR KR1020007000857A patent/KR20010022282A/ko not_active Application Discontinuation
  • 1999-05-25 EP EP99919477A patent/EP1004070A2/de not_active Withdrawn
  • 1999-05-25 JP JP2000551309A patent/JP2002517018A/ja active Pending
  • 1999-05-25 WO PCT/IB1999/000935 patent/WO1999061975A2/en not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events