Device for delineating zones in a video image display

• US 4,245,244 A
• Filed: 09/01/1978
• Issued: 01/13/1981
• Est. Priority Date: 09/01/1978
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Blake, James E., Lijewski, Robert R., Lambert, Thomas W.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Orsino, Jr., Joseph A.
• Application Number:
  US05/939,088
• Time in Patent Office: 865 Days
• Field of Search: 364/414, 250/445 T, 358/111, 358/183, 340/709, 340/710
• US Class Current: 378/98.5
• CPC Class Codes: G06F 3/033 Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor digitisers characterised by the transducing means G06F3/041
• CPC Class Codes: G06F 3/04842 Selection of displayed objects or displayed text elements G06F3/0482 takes precedence
• CPC Class Codes: H04N 5/32 Transforming X-rays cameras or camera modules for generating image signals from X-rays H04N23/30; circuitry of SSIS for transforming X-rays into image signals H04N25/30
• CPC Class Codes: Y10S 378/901 Computer tomography program or processor

Abstract

Data derived from multiple x-ray views of a body layer is processed in accordance with an image reconstruction algorithm by a central processing unit (CPU) to result in a matrix of digital data corresponding with picture elements (pixels) which are for being displayed on a tv or video monitor. A device for delineating or identifying a region in the displayed picture with a box, irregular trace, or cursor with a bright dotted line uses a trackball to generate data signals corresponding in position with pixels in the matrix. The trackball generated data is processed for producing video picture modulating signals corresponding with the pixels in the matrix to which they positionally relate. The modulating signals are overlayed on the composite video signals from the display controller with a video mixer.

Claims

1. A computerized tomography system comprising:

means for producing data representative of x-ray images resulting from absorption of an x-ray beam projected in a plurality of directions through a layer of a body,

a CPU operative to control said signal and to process said data in accordance with an image reconstruction algorithm resulting in a matrix of digital signals corresponding with picture elements (pixels) composing said layer as viewed perpendicular to the layer,

a video monitor having a display screen,

video display controller means for controlling said monitor and having memory means for storing said digital pixel signals in a matrix wherein the rows of said matrix correspond with horizontal scan lines on said screen as said monitor is operated in the raster scan mode, said controller being adapted to scan and read out said matrix of digital pixel signals, to convert them to analog video signals and to generate composite video signals for driving said monitor,

a pixel clock pulse generator for producing pulses in synchronism with the readout of said pixel signals,

a device for delineating a selected one of a box, a cursor, or a trace on said display screen while said picture is being displayed and independently of said CPU, said device comprising;

joystick means movable manually in the x and y directions and in resultant directions and means responsive to said movements by producing a train of pulses representative of the position of a box, cursor or trace which is to be delineated on said display screen and trains of pulses which are respectively representative of the size of said box in the x and y directions,

x-axis and y-axis position circuits including up-down counter means for counting the pulses representative of the x and y coordinates of the position of said box, cursor or trace and including register means for storing data representative of said position,

x-axis and y-axis size circuits including up-down counter means for counting the pulses representative of the x and y direction sizes of said box and including register means for storing data representative of said sizes,

an ALU having input means for said size and position data and having output means, said ALU being operative to calculate the coordinates of said size data relative to said position data and relative to corresponding locations in said matrix,

multiplexer means for coupling said position or size representative data to said ALU input means,

a comparator having input and output means, said input means being coupled to the output means of said ALU,

said pixel clock pulses controlling said comparator to produce an output signal whenever there is coincidence between the coordinates of any of said position or size representative data and the pixel in said matrix with which said data corresponds, and

a video mixer operative to superimpose said output signals on said composite video signal to thereby overlay a bright spot on said screen coincident with each output signal.

2. The device as in claim 1 wherein said joystick means comprises a fully rotatable ball,

said means which are responsive to movements of said ball by producing trains of pulses comprising a pair of encoders, one of said encoders producing pulses in response to said ball undergoing an x-direction component of movement and the other of said encoders producing pulses in response to said ball undergoing a y-direction component of movement.