Abstract: A video image composition system and method in which the artist can move an insert cut out of a foreground image relative to a background image while continuously observing on the monitor the instantaneous artistic effects of the varying composition, without any need to make an initial decision on exactly where to pin the insert. A soft-edged control image operates on the foreground image to cut the insert. By using a pen and a tablet, the artist moves the control and foreground images as a unit relative to the background image while being able at all times to view the monitor display of the dynamically changing, full composited image. The artist can thus rapidly assess a great number of different composited images before deciding where and how to pin the insert for the final composited image. An additional control image allows the artist to select from the background image a foreground object which always will be in front of the insert from the foreground image.

Abstract: An electronic graphic system for use in the painting of an image comprises a control store which stores control data representing a distribution of interpolation coefficients. The control data is created in a drawing process in which existing control data in the store is compared with new control data and is replaced with the new data when the new data has a value higher than that of the existing data. A combiner, in response to the stored control data, combines initial image data from an framestore with user selected color data from a store for display on a monitor. Also, the combiner can be reconfigured such that the combined data is written to the framestore replacing the initial image data therin. The system thus separates drawing operations from image modification operations, thereby providing a flexible means by which a simple binary line drawing algorithm can be used to paint into a color image.

Abstract: An electronic graphic system (1) comprises a memory (2) for storing data representing an image and a user operable stylus and touch tablet combination (4) by which the user can select a notional painting implement a color with which to paint and can create data defining positions in the image at which painting is to occur. An address generator (5) is arranged to generate address data identifying addresses in the memory (2) corresponding to the user created position data. The stylus and touch tablet (4) is pressure sensitive and generates a parameter depending on the pressure applied via the stylus by the user. The address generator (5) generates address data at intervals dependent on the instantaneous value of the pressure related parameter. In one embodiment the interval is a distance between identified addresses in the memory (2) and in another embodiment the interval is a period of time. In this way the system simulates an implement having a paint flow rate which is pressure related.

Abstract: A video image creation system provides intensity or color data from one or more stores. The image is created under manual control which effectively defines the coordinates of the artists implement at any given time.A processor receives the incoming image data and previously derived data from a frame store and modifies this data in dependance on a parameter available from another store. The created image can be viewed on a monitor.The parameter controls the contribution made from any adjacent, previously created, parts of the image and can be such as to simulate different pencil or brush shapes or types of paint for example. Additional facilities such as pressure sensitivity and blurring can be provided.

Abstract: Video image creation in which a raster-scan monitor displays an image comprising realistic, inherently non-aliased strokes created by combining proportions of the values of: (i) pixels defining a simulated brush moving along the image as an artist moves a pen on a tablet in continuous strokes; and (ii) the values of the pixels in the image that are under the brush at the time. The pixel values resulting from such combining replace the corresponding pixel values in the image so that, after an initial portion of a stroke, the pixel values in the image which are under the brush and therefore will be combined with the brush values comprise pixel values which are the cumulative result of a number of previous such combining operations. Manual pressure on the pen controls the proportions used in such combining operations. As the artist presses harder on the pen, the effect seen on the monitor is that more "paint" is applied.

Abstract: A system for manipulating video image signals, in which digitized composite video signals (i.e. D2 digitally encoded PAL or NTSC) are converted to component video signals (i.e. luminance and color difference signals) allowing selected pixels to be modified. In addition, the unconverted composite video signals are also stored and a key signal is generated which indicates which of the converted (i.e. component) pixels have been modified. An output signal is then produced by combining the manipulated signals and the unmanipulated signals in proportions determined by said key signal.

Abstract: A character generator provides video signals representing desired characters which may be held in a store capable of rapid access. The character information is processed in a manipulator to provide a change in shape, size or orientation for example. Field stores receive this manipulated information via switches as well as reference information from a generator. Read out from the respective field stores is arranged to occur when information is not being received by that store. After read out, the information is replaced by reference information, prior to the receipt of further manipulated character information. The reference information may be configured so as to include a portion of previously derived image data.

Abstract: A video processing system which can produce a different shape of output picture than the input. Addresses into which incoming picture points must be written to produce the desired shape changes are stored in a shape store. These addresses can also be manipulated in real time so that the position of the shape they define is changed. For example a Mercator projection of a map can be projected onto a globe and this globe could then be tilted, rotated etc.

Abstract: A character generating system is disclosed having a source of batches of video keying signals representing different characters combined with further keying signals representing a background for the respective character. The video keying signals are confined to one value range and said further keying signals are confined to a different value range. The system effects spatial transformation of the combined signals and responds to the values of the spatially transformed combined signals to derive shape signals corresponding to the further keying signals and to derive shade signals corresponding to the video keying signals. In response to the shape and shade signals different video signals are provided respectively representing the character and the background both spatially transformed as the combined signals were spatially transformed.

Abstract: A video processing system for generating an output sequence of video frames which, over time, a decreasing proportion of successive frames is derived from a first video input (21) and an increasing proportion of said frames is drived from a second input (22); an effect known as a wipe. A framestore (31) stores a frame of wipe-shape pixel signals wherein the value of each pixel represents the time at which the spacially corresponding output pixel is derived from the second video input signal. The wipe shape pixel signal are compared with a reference value, in response to which input signals are combined, and the reference value is adjusted between frames to create the wipe effect.

Abstract: A processing system and method which produces and manipulates images of a three dimensional object. Patches of video signals (called cameos) representing different parallel planes of an object are stored in a frame store from which each cameo can be accessed individually and manipulated as desired. When the effect of a change in orientation or position of the object is required in the output image each cameo is accessed and manipulated in the same manner and combined using key and priority signals. The manipulation is achieved by writing incoming video signals into addresses in a store determined by the manipulation required and provided as address maps. The medical embodiment replaces the cameos with frames of signals representing tomographic sections of a patient and uses a LUT to provide a window for certain ranges of signals.

Abstract: A video signal processing system in which a number of video image signals are combined to provide an output which is such that where several objects of the input images overlay so they appear to be at different distances. Each input video signal is provided with a priority signal and a series of contests are held within the processor so that the final image consists of the two video signals with the highest priority. A key signal is provided for the video signal with the highest priority.

Abstract: A system for converting video signals from a scanner from, for example, an air surveillance system comprising an interface (2) which applies incoming video signals directly to a bulk store (5) and to a scan converter (4). The interface can also apply signals from the bulk store to the scan converter. The signals received from the bulk store can be processed differently from those received directly by the scan converter. This system allows maximum possible resolution of the image to be maintained for zoom in and for roaming.

Abstract: A processing system includes a processor 10 and frame store 11. Both the frame store and processor are under the control of address mechanism 12. An incoming pixel is processed with previously stored information and the proportion of processed information restored is controlled to prevent errors in picture information density as store location may be accessed a number of times in a frame period. The addressing mechanism 12 can generate the desired information from address information which is only provided on some of the store locations and which is only updated over more than one frame period. The mechanism includes spatial and temporal interpolators to effect this operation.

Abstract: The image composition system includes framestores 30, 31 for receiving information from first and second picture sources. A processor 33 provides the composed image by using information from these sources. The processor is controlled by picture shape information made available from a third framestore 32. This shape information may be provided by a camera 26 receiving an image of a silhouette for example or the shape can be manually generated via a touch tablet 38. The instantaneous value of the shape controls the blending of the pictures such that portions of the picture can be taken from a scene and inserted without noticeable degredation. Manipulation of the position, orientation or size of the inserted picture portion for example can also be effected.

Abstract: A system for processing images typically still images from a slow scan source such as associated with an electron microscope. The analogue source is converted into digital form via an ADC and passes via an adder to a framestore. An output of the framestore is also received by the adder. The capacity of the framestore is sufficiently large to accommodate several hundred summed frames. The image is built up by using all the stored information and all the incoming information. A divider under the control of a frame counter automatically corrects for intensity as the summation of frames progresses, the result being available for monitoring via a digital to analogue converter. Additional mechanisms are disclosed for dealing with other aspects associated with differing frame rates.

Abstract: A processing system includes a processor 10 and frame store 11. Both the frame store and processor are under the control of address mechanism 12. The addressing mechanism 12 can generate the desired information from address information which is only provided on some of the store locations and which is only updated over more than one frame period. The mechanism includes spatial and temporal address interpolators to effect this operation.

Abstract: A video signal processor for effecting frame rate conversion. A number of framestores connected in series receive incoming video signals under the control of a first generator and are available from the respective fieldstores under the control of a second generator. The presence of respective one line delays allow two adjacent lines from the same field to be available for use by respective multipliers and thence to an adder. A comparator determines if significant movement is present and modifies co-efficients to the multipliers, made available from a co-efficient control so as to allow a single field to pass to the output if desired.

Abstract: A digital data manipulation system for compensating for drop outs on a video recording medium. Data received by an assembler is assigned to a predetermined non-standard format prior to recording. Addition of synchronizing information via process amplifier allows the digital data to be recorded on an analog video tape recorder as lines of video information. A checksum generator and parity bit generator are provided to effect two dimensional coding indicative of assigned data content both prior to recording and following playback. By detecting any differences between the coding information this identifies drop out errors to allow compensation therefor.

Abstract: A processing system for effecting angular displacement of at least part of a television picture. The picture is subdivided into picture areas each containing a plurality of picture points and a number of storage devices respectively receive information on each picture point within the area at a designated storage location. On read out, the location of a particular area is accessed by means of a picture point and line counter in a single read operation. Information on particular picture points within the area is selectively made available for interpolation via latches to allow construction of the displaced picture. The area accessed for read out can be modified relative to writing into the store in order to cope with any selected degree of displacement.