Abstract: A graphics blending feature for a terminal such as a home communication terminal (HCT) allows an overlay image to be selectively blended with a background image through the use of a chroma key function and one or more alpha control bits. The chroma key function is used to determine whether the overlay will be completely transparent or not, and the one or more alpha control bits are used to look up a larger alpha value used to blend the overlay and background images. By using a small number of alpha control bits to retrieve a larger alpha value for blending, memory requirements per pixel are reduced. The chroma key function may be implemented by comparing each overlay pixel value to a chroma value and, responsive to a match, making the overlay pixel transparent (i.e., no blending occurs). A dithering function is included in various embodiments to smooth out the resulting image.

Abstract: Since the corner detection means (7, 9) to detect each position of the blue board area from video signal, the conversion address generation means (11) to generate the conversion address based on the position information detected and the position information showing each corner position of the image area of video signal to be inserted and the image conversion means (16) to form conversion source video signal based on the conversion address are provided and the source video signal is to be inserted to the video signal, the operator's operation adjustment as the conventional device becomes unnecessary when inserting the source video signal into the prescribed frame of the video signal, and the operation of the operator can be further decreased. Thus, a video signal processing device capable of further decreasing the operator's operation can be realized.

Abstract: A method for segmenting a digital image into a foreground region and a key color region including characterizing a distribution of key color values; using the distribution of key color values to produce a multi-dimensional look-up-table having three or more dimensions indexed by color values in a selected color space to define a key color volume; addressing the multi-dimensional look-up table with color values of pixels in the digital image to determine whether the color values of such pixels are within the key color volume; and labeling pixels in the digital image whose color values fall within the key color volume to be within the key color region and labeling all other pixels to be within the foreground region whereby the digital image is segmented into the foreground region and the key color region.

Abstract: A picture switching apparatus for executing a fade-out/fade-in processing between adjacent video recording files includes a multiplier for multiplying a decoded video data with a multiplication coefficient (1-km), a multiplier for multiplying an output data of a data output circuit with a multiplication coefficient km and a data synthesizer for summing results of multiplication from the respective multipliers. The picture switching apparatus thus constructed performs the fade-out/fade-in processing without modification of the original video data for fading processing, by controlling km at the junction between the files such that the mining ratio of the color data for fading to a decoded color data is gradually increased/decreased.

Abstract: A picture replacement system for replacing a specified area of an original picture, with a desired picture comprising at least one camera for shooting an original picture of the subject; at least one irradiation unit for radiating a specified area of the subject with a predetermined invisible light ray; a picture generation unit for generating a desired picture that matches a size of the specified area; a detection unit for detecting the invisible light ray reflecting from the specified area that has passed around an obstruction in front of the specified area of the subject without being obstructed; a key signal generation unit for generating a key signal indicating a replacement area of the original picture based on a detection result of the detection unit; and a replacement unit for replacing the specified area within the replacement area with a desired picture corresponding to the key signal indicating the replacement area.

Abstract: A key signal processing apparatus for video signal processing including a signal delay circuit for successively delaying by 1 clock units a key input signal, used for applying a special effect to a video signal, and outputting the delayed key signal; a signal selection circuit for receiving the key input signal and a plurality of delayed key signals output from the signal delay circuit and selecting based on a selection control signal two pairs of signals in predetermined relationships of delay; a first signal interpolation circuit for performing signal interpolation on the first pair output from the signal selection circuit using a first coefficient; a second signal interpolation circuit for performing signal interpolation on the second pair output from the signal selection circuit using a second coefficient; and a signal synthesization circuit for combining a signal from the output of the first signal interpolation circuit and the output of the second signal interpolation circuit and outputting it as a key

Abstract: The present invention is useful in taking a visible light image for identification and other purposes without the requirement of a photobooth, regardless of the background of the visible light image. The original background of the visible light image is replaced with a preselected background. Two IR images with different intensities of IR illumination in the foreground and background regions of the scene, respectively, are compared to produce a difference image of light intensity differences between corresponding pixels of the two images. A binarized image is generated by binarizing the difference image with respect to a predetermined threshold value .theta.. A connectivity constraint is used to generate a binary mask from the binarized image, then a gray-scale mask is produced by multiplying the binary mask times a preselected modulation function of the difference image. Warping the gray-scale mask produces a transformed mask.

Abstract: The resolution of one or more components of image data is changed to generate scaled image data and transparency processing is applied to the scaled image data, wherein the transparency processing is taken into account during the changing of the resolution of the image data. In a preferred embodiment in which a video codec applies transparency processing during the compression of subsampled video data, the capture processor applies the same transparency mask during data subsampling to decrease color-bleeding effects that may otherwise appear in the decoded video stream.

Abstract: A live video insertion system efficiently places static or dynamic images into a live broadcast. The system initially identifies natural landmarks within the video scene that can be automatically identified and tracked as the field of view of the camera pans and zooms across the scene. The locations of the landmarks are mathematically modeled and stored as a constellation of locations on a mathematical grid. An arbitrary reference point, preferably not necessarily coincident with a selected natural landmark, is located within or without of the grid and used as an origin for the purpose of inserting the static or dynamic image within the field of view of the camera. For static images, it is frequently desirable to place an edge or border of the image to be inserted on the reference point. For dynamic insertions, the distance between the reference point and the inserted dynamic image is automatically changed from frame to frame in order to make the image appear as though it's translating or changing, or both.

Abstract: A special effect picture device is disclosed in which a transformed picture which is non-linear with respect to an original signal is formed using a video signal and a key signal for the original signal. A video signal is stored in a video signal storage unit and a key signal is stored in a key signal storage unit. The read-out addresses for the information concerning an upper picture of the transformed picture and the information concerning a lower picture of the transformed picture and also the information concerning the depth are generated by a read-out address generating unit. The key signal read out from the key signal storage unit and the video signal read out from the video signal storage unit are respectively divided by a dividing unit into upper and lower key signals and upper and lower video signals responsive to the read-out address for the upper picture and read-out address for the lower picture.

Abstract: A method of rendering at least part of an image from an at least one external source into a two-dimensional memory array having integer x and y pixel coordinates based upon a set of integer coordinates of an outline of the rendered image. The method includes the steps of forming a parallelogram defined by a parallel series of effect lines forming an angle e with either the x or y axis of the memory array and bounded on opposing ends of the scan lines by a scan axis, the parallelogram surrounding at least part of the two-dimensional memory array and rendering the image from the at least one external source into the memory array while moving unidirectionally along the effect lines and scan axis using the outline coordinates as transition points for selection and non-selection of the image.

Abstract: A video mixing apparatus for mixing a first video signal and a second video signal in accordance with a first key signal and a second key signal. The video mixing apparatus includes a key signal mixer for receiving the first and second key signals and generating and outputting a third key signal and a fourth key signal, wherein a level K.sub.1 of the first key signal, a level K.sub.2 of the second key signal, a level K.sub.p of the third key signal, and a level K.sub.m of the fourth key signal satisfy the relationships:K.sub.p =K.sub.2 -K.sub.1 K.sub.2,andK.sub.m =K.sub.1 +K.sub.2 -K.sub.1 K.sub.2 ;a key signal division section for receiving the third and fourth key signals and generating and outputting a fifth key signal, wherein a level K.sub.g of the fifth key signal satisfies the relationship:K.sub.g =K.sub.p /K.sub.

Abstract: A key signal processing apparatus for video signal processing including a signal delay circuit for successively delaying by 1 clock units a key input signal, used for applying a special effect to a video signal, and outputting the delayed key signal; a signal selection circuit for receiving the key input signal and a plurality of delayed key signals output from the signal delay circuit and selecting based on a selection control signal two pairs of signals in predetermined relationships of delay; a first signal interpolation circuit for performing signal interpolation on the first pair output from the signal selection circuit using a first coefficient; a second signal interpolation circuit for performing signal interpolation on the second pair output from the signal selection circuit using a second coefficient; and a signal synthesization circuit for combining a signal from the output of the first signal interpolation circuit and the output of the second signal interpolation circuit and outputting it as a key

Abstract: Creating a transition between a first sequence of video frames and a second sequence of video frames. The method includes storing a table of values that express a non-linear response to certain levels of light, generating a transition between the sequences, and adjusting the intensity at which material of the first sequence is displayed relative to the intensity at which material of the second sequence is displayed within the transition, based on the values stored in the step of storing.

Abstract: A key signal processing apparatus for video signal processing including a signal delay circuit for successively delaying by 1 clock units a key input signal, used for applying a special effect to a video signal, and outputting the delayed key signal; a signal selection circuit for receiving the key input signal and a plurality of delayed key signals output from the signal delay circuit and selecting based on a selection control signal two pairs of signals in predetermined relationships of delay; a first signal interpolation circuit for performing signal interpolation on the first pair output from the signal selection circuit using a first coefficient; a second signal interpolation circuit for performing signal interpolation on the second pair output from the signal selection circuit using a second coefficient; and a signal synthesization circuit for combining a signal from the output of the first signal interpolation circuit and the output of the second signal interpolation circuit and outputting it as a key

Abstract: The OSD includes a plurality of holding circuits for outputting to a mixing circuit pixel data for characters or patterns synchronously with a horizontal synchronization signal, wherein the pixel data for the characters or patterns to be displayed are supplied to the holding circuits by a memory through a plurality of channels, the number of which is equal to the number of the holding circuits, so that a display signal for displaying the pixel data in a plurality of display areas is generated by the mixing circuit.

Abstract: A video conferencing system and method that uses a central multimedia bridge to combine multimedia signals from a plurality of conference participants into a single composite signal for each participant. The system gives each conference participant the ability to customize their individual display of other participants, including keying in and out selected portions of the display and overlapping displayed images, and the ability to identify individual images in a composed video stream by click and drag operations or the like. The system uses a chain of video composing modules that can be extended as necessary to combine video signal streams from any number of conference participants in real time. Multimedia association software is provided for associating different media types to enhance display and manipulation capabilities for multimedia uses. The system also allows each user to dynamically change who can receive the information they provide to the conference.

Abstract: In a key signal waveform shaping apparatus which includes an adder 1 for supplying a key source signal KS with a gain of a predetermined slice level, a multiplier 2 for extending a signal offset by the adder 1 by multiplication of a gain, and a first limiter circuit 3 for converting the signal extended by the multiplier 2 by cutting an upper limit value and lower limit value of the extended signal. A limit value generating circuit generates an upper limit value and lower limit value from the signal offset by the adder 1. The key signal K is obtained by further limiting the output of the first limiter circuit 3 by the upper limit value and the lower limit value. The present invention provides a key signal waveform shaping apparatus in which an error of an edge position of a key signal can be removed and in which the quality of a synthesized picture can be improved.

Abstract: A mixer control circuit generates content control signals which are used by a mixer circuit to control the content of an output signal. The output signal will include either an analog signal, a digital signal or a mixture of the analog and digital signals. The level of a digital content control signal corresponds to the percentage of the output signal which includes the digital signal. The level of an analog content control signal corresponds to the percentage of the output signal which includes the analog signal. When the output signal includes a mixture of the analog and digital signals, a differential pair and an external control voltage are used to specify the percentage of each signal to be included within the output signal. During a horizontal blanking period, when the signals are being mixed, the differential pair and the external control voltage are bypassed and only the analog signal is included within the output signal.

Abstract: A method for separating a first image into two or more portions, such as foreground and background portions, based on the distance of the portions from a camera. The method includes detecting a main image using the camera, such as a CCD video camera and measuring distances from the camera to points in the first image. The method further includes separating the main image into two or more portions, such as background and foreground, based on the measured distance of these portions of the image from the camera. One or more of the separated images can then be combined with a secondary image to produce a composite image. To further refine the separation of the two portions of the main image, the contrast is determined between the two portions of the main image in regions of the main image having sufficiently large distance variations. The combining of the two images is then based on the determined contrast in addition to the distances.

Abstract: A method and a circuit for generating a composite video signal formed from a foreground signal and a background signal in accordance with the luminance self-key mode is described, in which the key signal is derived from the luminance foreground signal in dependence upon a clipping level. To avoid a quadratic dependence of the luminance signal during product formation of the key signal with the foreground signal (referred to as "double multiplication"), the linear key signal should be replaced by a control signal which is hyperbolically formed in such a way that the unwanted quadratic dependence is eliminated.

Abstract: A video effect is created with a video processing machine having a plurality of functions, each of which has a state that is selectively variable in response to change in an associated function parameter. The method comprises selecting a set of functions, specifying a starting keyframe containing a starting value for each of the parameters, specifying an ending keyframe containing ending values for the parameters associated with the functions of the selected set and vacancies for the other parameters associated with other functions, and specifying a number of video frames. The starting keyframe is used to place the machine in a starting state, in which each function has the status defined by the value of its associated parameter in the starting keyframe, and a first video frame is processed with the processing machine in the starting state.

Abstract: A method and apparatus for combining video signals with key signals whilst maintaining the integrity of the video signal and minimizing the effect of alias components. An analyser detects whether there are any high frequency components which would otherwise cause alias components. If such high frequency components are present, then low-pass filtering occurs. If such high frequency components are not present, then no unnecessary filtering occurs so as to maintain the absolute integrity of the video signal.

Abstract: A digital video effects generator includes: means for up-sampling the digital video component signals prior to their spatial transformation and linear interpolation, thereby reducing losses due to the (sin x)/x frequency response of the sampled video signal; means for spatially-mapping video motion data representing the degree of video data motion between temporally adjacent video frames and for motion adaptive interpolation to selectively blend interpolated video field data in accordance therewith; means for pre-transform keying, thereby allowing two video signal transformations to be keyed simultaneously; means for selectively transforming portions of input video signals, thereby allowing selective keying of non-spatially transformed video into selected regions of the video image; means for selectively linking keyframes within separate effects and providing smooth parametric transitions therebetween, thereby allowing several separate effects to be combined into a single effect with smooth parametric transit

Abstract: The present invention is useful in taking images for identification and other purposes without the requirement of a photobooth, regardless of the background of the image. The original background of the image is replaced with a preselected background. Two IR images with different intensities of IR illumination in the foreground and background regions of the scene, respectively, are compared for light intensity differences between corresponding pixels of the two images to form a mask differentiating between the foreground and background regions of the image. The mask is then applied to a visible light image of the scene and the preselected background is used to replace the original background.

Abstract: Disclosed is a technique for deriving a composite video image by merging foreground and background video image data supplied from a plurality of separate video signal sources employing pattern-key insertion, rather than prior-art color-key insertion, for this purpose. Pattern-key insertion involves replacing a first pattern in a video scene with a second pattern. This is accomplished by first detecting the first pattern in the video scene and estimating the pose of this detected first pattern with respect to a reference object in the video scene. The second pattern is then geometrically transformed using the pose estimate of the detected first pattern. Finally, the detected first pattern is replaced with the geometrically-transformed second pattern.

Abstract: Creating a transition between a first sequence of video frames and a second sequence of video frames. The method includes storing a table of values that express a non-linear response to certain levels of light, generating a transition between the sequences, and adjusting the intensity at which material of the first sequence is displayed relative to the intensity at which material of the second sequence is displayed within the transition, based on the values stored in the step of storing.

Abstract: A computer-based video editing system provides software controlled wipes between scenes. These wipes may be the conventional horizontal, vertical, or clock type wipes used in video to transition from one scene to the next. Instead of being generated by conventional digital wave form generators, the wipes are generated as a bit map in computer memory, thus allowing the editor to design his own wipes as desired. The wipes are generated by comparators which have as their inputs line-by-line video data and computer controlled threshold data so as to control a video switcher to select between scenes as determined by the wipe pattern.

Abstract: During the carrying out of a dim effect, a signal generated at a generator is mixed with a video signal and a matt signal at a mixer, a key signal and background signal are added at an adder, and the resultant signal is outputted. During the carrying out of a fade effect, in similar manner, the signal is mixed with the key signal and a fixed value signal at the mixer, the video signal and background signal are added at the adder, and the resultant signal is outputted. Extended dim effect and extended fade effect give depth to a picture with a color approximation where the depth of the image does not completely merge into the background.

Abstract: A color region extracting portion detects a specific color region from an input foreground image signal. A mapping portion categorizes an output signal of the color region extracting portion as a class. A high level resolution signal is generated with a predicting coefficient pre-learnt corresponding to the class. A threshold value Th is supplied from a terminal to a stretching portion. The stretch portion performs a stretching process. The stretching portion supplies a coefficient k as a key signal to a multiplier and a compensation signal generating portion. The compensation signal generating portion supplies a coefficient (1-k) to a multiplier. The multiplier multiplies the coefficient k by the coefficient (1-k) and outputs the result as a composite image of the foreground image and the background image.

Abstract: Any of multiple landmark regions of a scene being viewed by an image sensor are used for interring the location of a target region of the scene in which a pattern is to be inserted in order to avoid the problem of the view of a region being occluded. Because of changes, such as the pointing angle of the sensor, there is a slight difference in size and position in the location of a target region inferred from one landmark region and from another landmark region. this results in a jitter when a first landmark region being used for inferring the location of a target region is replaced by a second landmark region in response to the first landmark region being occluded. This jitter is eliminated by deriving an error-correcting component that compensates for the aforesaid slight difference in size and position in the location of a target region inferred from different landmark regions.

Abstract: An apparatus for use in a low-bit rate coding system is provided for preprocessing a video signal including interlaced even- and odd-numbered fields, each of the fields having video lines, and each of said lines consisting of pixels, resulting from scanning an image, to selectively define a window within the image before the video signal is coded for transmission in the low-bit rate coding system. The apparatus comprises a field window signal generator for providing a field window signal to enable the selective sampling of the field, a vertical window signal generator, in response to the fields window signal, for producing a vertical window signal to define the lines in the sampled field, and a horizontal window signal generator, in response to the vertical window signal, for producing a horizontal window signal to define the pixels for each of the derived lines.

Abstract: An apparatus and a method for synthesizing videos in a color video printer, in which videos can variously be edited and characters can simply be inserted into a video, according to a user's selection.

Abstract: An image processing system operates on first and second image data (V and Bg) to produce data defining a combined image. The first image data (V) represents a keyed image comprising a first object (F) keyed over a portion of a first background (B) in accordance with keying data (K). The second image data (Bg) represents a background. The system is arranged so that the second image data (Bg) is weighted by respective control data (.alpha.) related to said keying data (K) before being combined with the first image data (V). In another embodiment the first image data represents a second object independently keyed over the keyed image in accordance with second keying data and the control data is further related to the second keying data. In a further embodiment the first image data represents an image derived by cross fading between the first keyed image and a second keyed image.

Abstract: A method and system for combining digital data signals representing digitized images to implement a DSK operation in one mixing stage. The system requires only one mixing circuit, rather than two as in conventional DSK systems. In preferred embodiments, the DSK operation processes an input video signal having pixels a.sub.k, an input video signal having pixels b.sub.k, a stream of single-color pixels B, and a fade control signal .beta., to generate a stream of output pixels u.sub.k =(1-.beta.)v.sub.k +.beta.B, where v.sub.k =(1-.alpha.)a.sub.k +(.alpha.)b.sub.k, and .alpha. is a key signal which can have a different value for each pixel a.sub.k. The value of .alpha. can be constant for an entire frame of input pixels a.sub.k or can have a different value for each individual pixel a.sub.k. Typically, the value of .beta. is constant for each frame of input pixels a.sub.k. Preferred embodiments of the system employ a single mixing circuit, which receives five input data streams: first pixels a.sub.

Abstract: A circuit for analog chroma keying on color data permits display of graphics, generated from a computer system, and video on an output display. The analog chroma keying circuit receives the graphics signals and the video signals, wherein the graphics signals include color data to designate a color key. The analog chroma keying circuit includes a plurality of digital to analog converters that generate a plurality of color key limits for defining a range to detect the color data denoting the color key. The analog chroma keying circuit also includes a plurality of comparators coupled to receive the graphics signals and the color key limits for each primary color. The plurality of comparators generate a key on indicator when the graphics signals fall within the color key limits.

Abstract: For correcting vignetting in the upper or lower range of the pick-up area of optoelectric transducers of a multichannel color television camera with zoom lens are described, a representative signal is derived from the diaphragm aperture setting and from the zoom setting. Dependent on corresponding signals for the minimum diaphragm aperture, on the one hand, and the minimum values for wide-angle and telesetting of the zoom range, on the other hand, these representative signals generate control voltages with which the level of a field frequency sawtooth signal is controlled. Finally, this sawtooth-shaped control signal influences the video signal of each chrominance channel in the sense of a vignetting compensation.

Abstract: A digital video effects generator includes: means for up-sampling the digital video component signals prior to their spatial transformation and linear interpolation, thereby reducing losses due to the (sin x)/x frequency response of the sampled video signal; means for spatially-mapping video motion data representing the degree of video data motion between temporally adjacent video frames and for motion adaptive interpolation to selectively blend interpolated video field data in accordance therewith; means for pre-transform keying, thereby allowing two video signal transformations to be keyed simultaneously; means for selectively transforming portions of input video signals, thereby allowing selective keying of non-spatially transformed video into selected regions of the video image; means for selectively linking keyframes within separate effects and providing smooth parametric transitions therebetween, thereby allowing several separate effects to be combined into a single effect with smooth parametric transit

Abstract: An image processing system for applying a video special effect to input image data. The system comprises a memory for storing image processing data; a coefficient generator for generating coefficients on the basis of the image processing data stored in the memory; a signal processor for processing the input image data on the basis of the coefficients outputted from the coefficient generator; an external storage unit for storing plural kinds of image processing data; and a controller for controlling the memory, and the external storage unit in such a manner as to transfer a desired one of the plural kinds of image processing data to the memory.

Abstract: A video signal combining apparatus for combining at least three video signals (V.sub.A, V.sub.B, V.sub.C) including a key signal (K.sub.A, K.sub.B, K.sub.C) and depth signal (Z.sub.A, Z.sub.B, Z.sub.C) includes at least two cascade-connected 2-input combiners (1, 2) which combine two of the video signals so that the output of a preceding stage becomes one input of the next stage; a decision circuit (3) which decides on a pixel by pixel basis on an order of arrangement in a depth direction among images from the depth signal of the input video signals; and a switching circuit (4) which rearranges the input video signals in an order of arrangement based on the result of decision of the decision circuit (3) and outputs the result in a parallel manner to the inputs of the above-described combiners (1, 2) so that the video signals are sequentially combined in the decided order of arrangement.

Abstract: A video signal generating apparatus comprises a first microprocessor (10) including a memory (16) for receiving and storing in non-real time instructions for the generation of a range of video signals, such as test patterns, digital multi-effect keys or wipe patterns for a digital switcher, and a second microprocessor (14) for reading the instructions and generating a selected required video signal in real time.

Abstract: A digital image compositing system (20) has background, foreground, key and mask busses (22), (24), (26), and (28). An analog key input (30) is connected to the key and mask busses (26) and (28) through an analog/digital (A/D) converter (32) by crosspoint switches (34). Four digital D1 video signal inputs (36) are connected to the busses (22-24) through additional crosspoint switches (34). The key and mask busses (26) and (28) are respectively connected to frame stores (38) and (40). A key processing toolkit subsystem (42) is connected to the output of the frame stores (38) and (40). A compositor subsystem (44) is connected to the background and foreground busses (22) and (24) and to the output of the key processing toolkit subsystem (42). A D1 program output (46) is connected to the output of the compositor subsystem (44) on program bus ( 48). A D1 key output (50) is connected to the output of key processing toolkit subsystem (42) on processed key bus (52).

Abstract: A shaped video having an input key control signal associated therewith is processed by carrying out a first operation on the input key control signal to provide a first processed signal, carrying out a second operation on the first processed signal to provide a second processed signal, and combining the shaped video signal and the second processed signal to provide an output video signal. One of the first and second operations comprises translation. In this manner, a simulated shadow is added to the shaped video signal.

Abstract: A chroma keyer with fringe control offset adds a fringe control offset value to a correlation output produced by a hue selector. The hue selector compares the hues of a foreground image, representing a foreground object in front of a reference matte background, with a reference hue corresponding to the reference matte background to produce the correlation output. The adjusted correlation signal is then negatively clipped and provided at the output of the hue selector as a hue select signal that is used for deriving a chroma key signal and for providing background suppression to the foreground image.

Abstract: In a special effects apparatus that processes an input video signal in accordance with a key signal representing an image pattern, a processing circuit processes the input video signal in accordance with the key signal and outputs a processed video signal which is stored in a video memory and fed back from the video memory to the processing circuit for further processing of the processed video signal in accordance with the key signal and the input video signal. A motion detection circuit detects motion of the image pattern represented by the key signal and a control circuit prevents the processed video signal from being stored in the video memory when the motion detector does not detect motion in the image pattern so that a desired soft-edged special effect can be maintained when there is no motion of the image pattern represented by the key signal.