US 4,790,028 A · Method and apparatus for generating variably scaled displays

Abstract

Portions of an image generated on an electronic display device are magnified for closer examination while other areas are compressed so that no material is lost from the total viewing area. To achieve this, the image is divided into segments with some assigned scaling functions having values greater than one and others assigned scaling functions having values less than one in a manner such that the mean value of the scaling functions across the screen is one. A transformation function is generated for each segment as a function of the assigned scaling functions. Each image point is then transformed using the appropriate transformation function an a rescaled image is generated from the rescaled image points. The variably scaled image can be generated on a touch screen device such that an area to be magnified can be designated by touching the screen at the desired location and the value of the scaling function can be set as a function of the length of time that the screen is touched.

Claims22

Dependent claims

A method of variably rescaling a total image composed of a plurality of image points disposed within boundaries of the total image for display within a display area of fixed dimensions, without altering the boundaries of the total image displayed, said method comprising the steps of:

dividing the total image into image area segments,
assigning a selected scaling function to each image area segment, each said selected scaling function being assigned such that the selected scaling function in at least one image area segment has a value greater than one and the selected scaling function in at least another image area segment has a value smaller than one, but with the selected scaling functions over the total image having a mean value equal to one in all directions,
generating an associated transformation function for each image area segment as a function of the selected scaling function,
generating transformed image points for each image area segment in accordance with the associated transformation function, and
generating in said display area of fixed dimensions a rescaled image utilizing the transformed image points such that the total image remains displayed although at least one image area segment of the total image is magnified.

2 more elements

Apparatus for variably rescaling a display composed of a plurality of image points disposed within a total image area of a predetermined size without altering the size of the total image area displayed, said apparatus comprising:

memory means for storing signals representative of image points on the display;
means for generating input signals representative of segments of the total image area to be magnified and scaling functions therefor;
a digital computer programmed to generate in response to said input signals, scaling functions for segments of said total image area outside the segments of the total image area to be magnified such that a mean value of the scaling functions across the total image area is equal to one, to generate a transformation function for each total image area segment as a function of the scaling function generated therefor, and to generate rescaled image point signals by applying an appropriate total image area segment transformation function to each of the image point signals stored in memory,
a display generator to which said rescaled image point signals are applied to generate display signals, and
a display device to which the display signals are applied to generate a variably rescaled visual display composed of rescaled image points.

2 more elements

Dependencies are inferred from the claim text.

Method and apparatus for generating variably scaled displays

Life of this patent

Method and apparatus for generating variably scaled displays

Life of this patent

Abstract

Claims22