Abstract: An enhanced video special effects system architecture is based on deinterlacing (16) incoming fields of interlaced video and processing the deinterlaced video through video special effects operations (18, 30), each of which benefits from operating on a progressive scan video signal rather than an interlaced video signal.

Abstract: Special effects using polar image coordinates produce a new class of television special effects, such as spherical mapping and kaleidoscope effects. Rectangular coordinates for an input image are converted into polar coordinates, and the polar coordinates are mathematically manipulated according to the desired special effect. The modified polar coordinates may be applied directly to the rectangular coordinates to produce modified rectangular coordinates that represent the desired special effect, or they may be converted back into rectangular coordinates as the modified rectangular coordinates.

Abstract: A method of processing a foreground array of sample values, a background array of sample values and a crop array of sample values, which three arrays are coextensive and wherein the crop array represents a geometrical figure associated with a non-zero multiplication factor surrounded by a marginal area associated with a zero multiplication factor, comprises selecting a low-pass filtering operation to be carried out on the foreground array, and modifying the crop array so that when the selected low-pass filtering operation is carried out on the modified crop array, the sample values at the periphery of the domain of the resulting filtered crop array are all associated with a zero multiplication factor. The selected low-pass filtering operation is carried out on the foreground array and the modified crop array to provide a filtered foreground array and a filtered crop array respectively. The background array and the filtered foreground array are combined under control of the filtered crop array.

Abstract: A diagnostic system for a digital signal processor, having an input module, an output module and a plurality of successive processing modules defining a signal processing path, monitors various internal test points within each module. Any one of the test points may be connected to a diagnostic bus. The output of the diagnostic bus may be appropriately modified and input to the output module in lieu of the digital signal from the last processing module to provide a diagnostic display.

Abstract: The central difference along a selected axis through a point (u, v) of a rectangularly-sampled luminance field and at an arbitrary angle .alpha. is computed by interpolation. The octant in which the selected axis lies is identified, and first and second pixels through which the lines that limit the identified octant are identified. The first and second pixels are adjacent each other in the luminance field array and lie on a common ordinate or a common abscissa. The difference between the luminance values of the first and second pixels is calculated. Third and fourth pixels, which are symmetrically disposed with respect to the first and second pixels respectively about the point (u, v), are identified, and the difference in luminance values of the third and fourth pixels is calculated. The central difference along the selected axis is calculated by applying the MIX operator to the two difference values and a mix ratio coefficient which is the tangent of an angle which is related to .alpha.

Abstract: A method for orientating and animating video images using quaternions to provide smooth, predictable rotations in a digital video effect device. Euler angles for a new orientation are input by an operator and are converted into an appropriate quaternion. For incremental orientation changes the appropriate quaternion is combined with the current quaternion of the video image in either source or target space to form a new quaternion for the new orientation of the video image. A selected plurality of such new quaternions in a sequence make up the video effect keyframes. In executing the video effect a Bezier spherical linear algorithm is used to interpolate intermediate quaternions on a video field by field basis between neighboring pairs of keyframe quaternions based upon the source keyframe quaternion, the destination keyframe quaternion, a source outgoing keyframe quaternion, a destination incoming keyframe quaternion and an inbetweening time coefficient.

Abstract: A mixer controlled, variable passband, finite impulse response filter has a plurality of individual filter function blocks which are cascaded. The filter function of each of the individual filter function blocks is represented by a fixed filter function block having a linear phase response. The junctions between successive filter function blocks form signal taps. The signal from each signal tap is delayed by a compensating delay device so that the signals from each of the plurality of signal taps have the same phase function. Signals from selected signal taps are then combined in a predetermined manner to achieve a desired filter transfer function.

Abstract: A method and apparatus is disclosed which provides for the placement of a border video signal around a selected object in a video image. A video image of the selected object is first inserted into a video image of a selected border video signal in a video mixing process by use of a key signal defining the selected object. The key signal is further processed to transform the step transitions associated therewith between the zero and full insert states into non-step transitions. The transformed key signal is thereafter used to control a subsequent mixing of the resulting image of the selected object inserted into the video image of the border video signal with a background image to produce a composite video image.

Abstract: The central difference along a selected axis through a point (u, v) of a rectangularly-sampled luminance field and at an arbitrary angle .alpha. is computed by interpolation. The octant in which the selected axis lies is identified, and first and second pixels through which the lines that limit the identified octant .Iadd.extend .Iaddend.are identified. The first and second pixels are adjacent each other in the luminance field array and lie on a common ordinate or a common abscissa. .[.The difference between the luminance values of the first and second pixels is calculated..]. Third and fourth pixels, which are symmetrically disposed with respect to the first and second pixels respectively about the point (u, v), are identified.[., and the.]..Iadd.. The .Iaddend.difference in luminance values of the .Iadd.first and .Iaddend.third .[.and fourth.]. pixels is calculated.Iadd., and the difference in luminance values of the second and fourth pixels is calculated.Iaddend..