Abstract: A rising cuff pressure detects the diastolic blood pressure and continues to rise to generate a pulse amplitude profile. The systolic blood pressure is determined by a computation using data from the profile to discriminate against the contribution of a hardened artery, without requiring the cuff pressure to exceed the systolic blood pressure.

Abstract: A rising cuff pressure detects the diastolic blood pressure and continues to rise to generate a pulse amplitude profile. The systolic blood pressure is determined by a computation using data from the profile to discriminate against the contribution of a hardened artery, without requiring the cuff pressure to exceed the systolic blood pressure.

Abstract: A video signal is generated representative of a background scene, such as a weather map, which provides an outline of all the detail in the map. This outline detail is made visible to a foreground subject by projecting it onto a white screen behind the subject in a selected color such as green. The projector is selectively inhibited so as to prevent the background detail from projecting onto the foreground subject. The white screen and the green detail lines are removed and replaced by the background scene by an image compositing process. Prompts are visible to the foreground subject, but not visible to a home viewing audience.

Abstract: A method for automatically implementing and coordinating the techniques of creating the illusion of illumination changes on a foreground subject that should occur when the subject moves throughout the various illumination levels on the background of a composite image.

Abstract: A video projector shows the desired scene on a projection screen. An infrared source close to the video projector uniformly floods the projection screen with non-visible infrared radiation. An infrared sensitive camera, also close to the video projector, observes the projection screen and sees only the uniform infrared illumination of the screen. Upon entry of a subject into the projected video image, the infrared reflected from the subject will not match that of the projection screen and thus the subject area is identified. All pixels of the projected scene, in the area occupied by the subject, are inhibited before reaching the video projector. The subject may then look directly at an audience without being blinded by the projector.

Abstract: A method and apparatus used in the field of image compositing which eliminates the need to obtain an original clear frame of the backing during production, by synthesizing during post production a clear frame of the backing from a frame of the foreground scene that includes the subject as well as the backing. This synthetic clear frame eliminates the problems of obtaining a registered clear frame during production, and thereby permits the ready application of nonuniformity correction to image compositing in both motion pictures and graphic arts. The invention is also directed to a method and apparatus used in the field of image compositing which reduces the processing time for developing the inhibit signal that prevents the corrections from being applied to the subject, the control signal E.sub.c, and a number of other functions that are computed from the colored backing.

Abstract: The invention is a method used with a system for compositing a foreground scene including a subject before a nonuniformly illuminated colored backing, and a background scene, and where the nonuniformity is nonlinear from side to side and/or nonlinear from top to bottom. A window is employed to mask unwanted areas outside of, or on, the colored backing and one or more window edges form a visible join line where the window edges join the backing. The visible join line is made nonvisible without affecting the subject by a horizontal and vertical linear interpolation method for obtaining backing corrections that cause the backing level control signal to be uniform at the window edges and match an assigned window signal level.

Abstract: A method and apparatus used in the field of image compositing which eliminates the need to obtain an original clear frame of the backing during production, by synthesizing during post production a clear frame of the backing from a frame of the foreground scene that includes the subject as well as the backing. This synthetic clear frame eliminates the problems of obtaining a registered clear frame during production, and thereby permits the ready application of nonuniformity correction to image compositing in both motion pictures and graphic arts. The invention is also directed to a method and apparatus used in the field of image compositing which reduces the processing time for developing the inhibit signal that prevents the corrections from being applied to the subject, the control signal E.sub.c, and a number of other functions that are computed from the colored backing.

Abstract: A linear image compositing system which corrects for nonuniform luminance and/or color of the colored backing without incurring the penalties of edge glow, edge darkening, loss of edge detail and other anomalies. A control signal is created directly proportional to the luminance of the colored backing and controls the level of the BG scene. Unless the control signal is corrected, the background scene will contain all the brightness and color variations occurring on the colored backing. Correction factors are developed by comparing the RGB video obtained from the backing before the subject is put in place, with the ideal values of RGB that would have been obtained from a perfect backing. These correction factors correct the RGB video when the scene is scanned with the subject in place. The control signal, being zero in the subject area, may be used to inhibit the corrections in the subject area.

Abstract: A linear image compositing system which corrects for nonuniform luminance and/or color of the colored backing without incurring the penalties of edge glow, edge darkening, loss of edge detail and other anomalies. A control signal is created directly proportional to the luminance of the colored backing and controls the level of the BG scene. Unless the control signal is corrected, the background scene will contain all the brightness and color variations occurring on the colored backing. Correction factors are developed by comparing the RGB video obtained from the backing before the subject is put in place, with the ideal values of RGB that would have been obtianed from a perfect backing. These correction factors correct the RGB video when the scene is scanned with the subject in place. The control signal, being zero in the subject area, may be used to inhibit the corrections in the subject area.

Abstract: In the present invention, certain improvements are incorporated that permit removal of the backing color when its illumination is of non-constant color. In addition, an improved color logic is described that improves the simultaneous reproduction of fleshtones and green foliage in the same scene. A modified control logic is described that improves reproduction of red objects and fleshtones. A reversed window permits retention of objects whose color is identical to that of the backing. And, finally, a circuit is described which permits a super-imposing of titles or glow where said titles or glow may be made wholly transparent, semi-transparent or opaque.

Abstract: A method and apparatus to cause a colored backing to be replaced by a background scene, such that the composite scene shows no loss of detail, no edge anomalies, no evidence of a colored backing having been present, and no evidence that the final scene is a composite, even when the foreground scene contains fine strands of hair, glassware, smoke, fog, or other semitransparent subjects. Control signals E.sub.b and E.sub.c are created to cause the foreground and background scenes to mutually interact in a natural manner, so that shadows on the colored backing appear as shadows on the background scene, and the luminance of the background selectively causes back and edge lighting of foreground subjects. The hue and luminance of the colored backing are continuously and automatically tracked and removed by a subtraction process. The background level is automatically held constant even though backing illumination changes.

Abstract: A linear color television compositing system of the "blue backing" type, in which the foreground signal channel is always open. The foreground and background channels are not switched by the edges of the pictorial subject matter.The hue of the colored (typically blue) background is removed by vector subtraction and the luminance thereof by arithmetic subtraction.Flare illumination of the foreground subject(s) from the backing is removed, improving color fidelity.The background pictorial scene that takes the place of the removed colored backing area is linearly turned up or down, allowing shadows of foreground subjects to appear in the background.

Abstract: The linear foreground and background compositing system of the "blue-screen" type and as included in my prior U.S. Pat. No. 4,100,569, is provided with non-linear background control signals for improved composite picture quality under various adverse circumstances. More particularly, the problem of footprints, scuff marks, and dust on the "blue-screen" background for the foreground signal has been eliminated by a "clean-up" circuit 98 which shifts the background signal to "fully on" when it reaches a level in the vicinity of 80 or 90 percent "on", and making a concurrent reduction in the foreground signals, so that above the selected control level shadows or semi-transparency objects are made fully transparent and are not reproduced. The problem of "print-through" in the case of glossy black objects has been avoided by a circuit 34 which reduces background signal to zero when the level of blue foreground signals drops below a predetermined level.

Abstract: Lenticular projection screens of improved optical accuracy and uniformity are produced by deriving the specular surfaces of all lenticules within at least a major screen area from a common unitary optical surface, typically using replication by electroforming. The initial master surface is typically formed by conventional machining and polishing of a body having axial symmetry in the general shape of an ogive. The unitary convex surface of revolution of the ogive is repeatedly replicated, and like sections of each replica are isolated and assembled on a transparent reference surface. The assembled sections are adhered to a stiff back, and the optical assembly face is replicated. Multiple replicas of the initial assembly are typically again assembled and replicated, leading ultimately to unitary panel units which form the projection screen.

Abstract: Lenticular projection screens of improved optical accuracy and uniformity are produced by deriving the specular surfaces of all lenticules within at least a major screen area from a common unitary optical surface, typically using replication by electroforming. The initial master surface is typically formed by conventional machining and polishing of a body having axial symmetry in the general shape of an ogive. The unitary convex surface of revolution of the ogive is repeatedly replicated, and like sections of each replica are isolated and assembled on a transparent reference surface. The assembled sections are adhered to a stiff back, and the optical assembly face is replicated. Multiple replicas of the initial assembly are typically again assembled and replicated, leading ultimately to unitary panel units which form the projection screen.

Abstract: In a system for combining foreground video images with background video images, using the so-called "blue-screen" (or special background color) technique, a comprehensive control system is provided which accommodates a broader range of foreground objects, permits the careful coordination of control of the blue of the foreground with the level of the background signals, and also permits precise shadow control in accordance with the artistic requirements of the scene to be produced. To properly control the level of the blue from the foreground and to properly distinguish between situations where the video signal arises from solid or partially transparent actual foreground objects and where it originates from the blue screen, various electrical adjustments are provided for accommodating different types of foreground objects.

Abstract: A multiple channel motion picture sound record is reproduced with selective ontrol of the cross-talk between channels due to film weave. Such control is effected by lateral offset of the respective sound sensors, and conserves limited available width of the sound record. Also, tracks at both edges of a multi-track record are modulated in like phase by a common sound channel to minimize certain effects of film weave.

Abstract: Improved electronic compositing procedures and apparatus are described, ed typically on the blue screen process and suitable for processing motion pictures of professional quality and the like. The invention provides compensation for color impurity in the backing illumination over a continuous range of effective transparencies of the foreground scene. Applicant's previous method for limiting the blue video component for the foreground scene to permit reproduction of light blue foreground objects is improved by a dual limitation criterion which simultaneously suppresses blue flare light from the backing reflected by foreground objects of selected colors, typically including grey scale and flesh tones.

Abstract: Sound is recorded on color motion picture film in the form of variations of ue rather than overall density, with inverse density variations of different color media of the film directly superposed. With three distinct color media it is possible in that manner to record two separate sound channels, the respective channels being hue modulated on distinct hue axes. Such hue modulated sound records are inherently virtually free from noise due to occlusions such as dirt and scratches on the film. Apparatus is disclosed for recording sound in the described manner and for reproducing sound from such records, including electronic means for reducing additional forms of noise. The inherent reduction of noise permits the normal sound track area of conventional films to accommodate several distinct tracks, each of which can carry two distinct sound channels or one sound channel and a control channel.