Abstract: A method of providing file data for a media file from a file system, where the format of the file requires that the file comprise a plurality of segments of file data located at pre-declared locations within the file. The file data making up the file is based upon derived file data. After receiving a request to open the file, a maximum segment length for the file is determined based on the desired properties of the file. In response to a request for the location of a segment within the file, a location calculated by considering each segment of the file to have the maximum segment length is returned. In response to a request for file data from a segment of the file, generated file data for the segment is returned, where the generated file data comprises the derived file data and padding data to give the generated file data the maximum segment length.

Abstract: The present invention seeks to provide an improved file system that provides essence data for a media file in a way that does not require the contents of the entire file to be available before any file data can be provided. The present invention is reflected in a method of providing file data for a media file of a pre-determined format from a file system comprising a file record database and a data store, wherein the media file corresponds to a programme. The method comprises the steps of receiving details of the programme including the duration of the programme, and determining the layout of the media file in the pre-determined format from the received details of the programme, the layout including locations for essence data within the file. A file record for the media file is then created in the file record database. In response to a request for the location of essence data within the file, a location given by the determined layout of the media file is returned.

Abstract: A method of providing file data for a media file from a file system, where the format of the file requires that the file comprise a plurality of segments of file data located at pre-declared locations within the file. The file data making up the file is based upon derived file data. After receiving a request to open the file, a maximum segment length for the file is determined based on the desired properties of the file. In response to a request for the location of a segment within the file, a location calculated by considering each segment of the file to have the maximum segment length is returned. In response to a request for file data from a segment of the file, generated file data for the segment is returned, where the generated file data comprises the derived file data and padding data to give the generated file data the maximum segment length.

Abstract: A method of providing file data for a converted video file from a file system. After receiving a request for a portion of file data from the converted video file, an existing video file from which to derive the file data is determined. A portion of file data from the existing file that corresponds to the requested portion of file data is then determined, and file data from the portion of file data from the existing file data, by converting the portion of file data to file data of a different quality. The generated file data is then returned.

Abstract: A method of providing file data from a file system comprising a data store and a file record database. The method comprises the steps of receiving a request to open a file in the file system and determining the desired properties of the file using the syntax of the request. A file record is then created in the file record database based on the determined properties of the file, and a file handle for the file record is returned. Data constituting the requested file from data in the data store is generated based on the determined properties of the file, and in response to a request to read a portion of data from the file, a corresponding portion of the generated data is returned.

Abstract: The invention provides a network-based video editing system, in which video clips are made available on demand to servers located in a plurality of spatially separated zones linked only via the network. In order to ensure that cautionary or advisory information contained in signs or signals (“tags”) associated with certain video material is retained during transfer between servers in different zones, the invention provides that new tags associated with video material in any zone are broadcast generally to all other zones. Only tags associated with video information currently stored in any zone are retained in that zone, but all tags associated with information copied from a first zone to a second zone are supplied to the second zone. In a preferred system, the video material is time-stamped to permit conflicts in the content of multiple tags relating to the same video material to be resolved by making the most recent prevail. The invention also provides a method for operating such a system.

Abstract: There is described an editing system in which image data representing an initial moving image input in a first format at a corresponding rate is stored in a store and is manipulated to produce image data representing an edited moving image for output in a second format at a corresponding data rate. The system is arranged such that processing is effected at a data rate which is variable and determines the second data rate.

Abstract: An electronic graphic system comprises an image store for storing data defining an image, a stylus and touch tablet device for generating position data representing a sequence of positions including a first position, a brush store for storing data defining a drawing implement, and processor for processing data in the image store. Data is processed by reading patches of initial image data from the store at locations related to the position represented by the position data. An image value is determined as the value of a predetermined pixel in a patch of data at a location corresponding to the first position. Patches of image data are modified with the determined image value depending on the brush data.

Abstract: A chroma keying system 1 processes foreground image data representing a foreground subject in front of a matte, together with background data representing a background image, to produce composite image data representing the foreground subject and the background in place of the matte. A programmable look up table 8 is provided for receiving on a pixel-by-pixel basis the most significant bits (MSBs) of the foreground image data and outputting in response thereto range data representing limits of a keying range. An interpolator 9 is also provided for interpolating the range data depending on the least significant bits (LSBs) of the foreground image data and outputting keying data. A combiner 4 combines the foreground image data and the background image data on a pixel-by-pixel basis in response to the keying data to produce the composite image data. The system is operable in a calibration mode in which a generator 15 is connected to input the colour point data to an external keyer.

Abstract: A video processing system comprises a video store 7 for storing video data defining a plurality of clips. For each of the clips an associated set of clip data is stored in an editing memory 12. Each set of clip data comprises processed data identifying processing to be applied to the video data forming the clip and history data identifying the origin of the clip. The video data forming the clip or clips is processed by a processor 6 in accordance with the processing identified by the process data associated with the or each clip to produce video data forming a process clip for storage in the video store 7 and an associated set of clip data for storage in the editing memory 12.

Abstract: An electronic graphic system 1 processes image data defining color values of a multiplicity of pixels that together form an image. The system 1 comprises a processing unit 14 in which image data from an image store 2 is processed with other image data from a store 9. The processing is effected on a pixel-by-pixel basis depending on control data in a control store 15 and on a predetermined gamma factor defining a relationship between color values and corresponding light values. The processing unit 14 thereby produces processed color value data representing a manipulated version of the image in which the light content of pixels has been varied by the other image data depending on the control data and the gamma factor.

Abstract: A signal processing system 20 comprises a source 22 of video signals representing pixels in a first format (e.g. 4:4:4). The video signals are coarsely processed by a filter 43 and interpolator 44 and the processed signals are compared by a comparator 46 with the video signals. Depending on the result of the comparison either signals from the filter 43 or signals from a filter 30 are selected for output as video signals representing the pixels in a second format (e.g. 4:2:2).

Abstract: An image processing system 11 is arranged to produce data representing a combined image from foreground data F representing a foreground subject in front of a chroma backing and background data B representing a background image. The foreground data is processed and color corrected to produce first and second processed foreground data which is combined in a combiner 25 under the control of a first key K1. The background data is processed using a second key K2 to “cut” a “hole” in the background image. The processed background data and the combined foreground data are added together in an adder 44. A third key K3 is used to remove unwanted data from the added foreground and background data and to combine the resulting data with the processed background data in a combiner 45.

Abstract: A video processing system for use in creating apparent three dimensional movement of a two dimensional video image on a display screen 20. At least one set of axes is displayed on the image to be moved. A computer 24, in response to signals from a user operated stylus 21 and touch tablet 22, controls the manipulation of image data in an image store 26 to control apparent rotation of the image about, and/or linear movement along, an axis selected by the user. In the described embodiment several sets of linked axes are defined. Rotation or linear movement with respect to an axis is controlled respectively by selecting a marker identifying the axes or a line representing the axis. Selection is made by way of a cursor under the control of the stylus and touch tablet. The system can also display a line representing the user defined movement of e.g. the center of the image.

Abstract: A pixel image at broadcast or graphics resolution is spatially transformed to represent the 2D projection of an image that has undergone movement in 3D space or is seen from a different viewer's position. For example, an image on a screen is delineated with four reference points designated by touching a pen on a tablet and then one is dragged with the pen along the screen to change the shape of the delineated image. At the same time, the entire delineated image is spatially transformed to make it continue to fill the entire changing shape and only that shape, until the dragged reference point is pinned to fix its position on the screen. Two or more designated point can be selected to move together as the pen drags them along the screen. The image being spatially transformed can be combined with a second image under the control of a stencil image to form a composite image.

Abstract: The system comprises a store 11 having several disc drives for storing multiple video frames in random access order. The store 11 also has at least two ports 15, 16 each capable of transferring data relating to a respective video clip at video rate. The system further comprises processors 27, 28 for processing frame data associated with at least two video clips and a monitor for displaying selected ones of said multiple video frames. In a preview mode of operation video clips can be read from the store 11, combined and displayed on the monitor at video rate, and changes can be made to the clips and the manner in which they are combined without committing the combination to the store.

Abstract: An electronic graphic system includes an image store for storing in a multiplicity of storage locations data representing a multiplicity of image pixels which when displayed together form an image. A user operable input device generates control data in response to user operation thereof. An implement data store stores data defining a patch of implement pixels which together represent a profile of a drawing implement.

Abstract: An electronic graphic system comprises an image store for storing data defining an image, a brush store for storing data defining a drawing implement and a stylus and touch tablet for inputting position data and other data. A spatial filter is arranged to respond to the data from the stylus and touch tablet device to filter the brush data to produce brush data defining a drawing implement of a size depending on the data from the stylus and touch tablet device. The filtered brush data is used by a drawing processor to process data in the image store.

Abstract: A video image processing system 1 comprises a monitor 5, a stylus/touch tablet device 6 and a processor 3, 7, 30 for processing frames of a video clip. The processor is responsive to the stylus/touch tablet to generate data representing a time-based function defining the manner in which a parameter of the video clip varies with the time of the clip. The processor is arranged to generate data for display on the monitor of a graph representing the plot of the function. The processor also responds to operation of the stylus/touch tablet device by manipulating the graph data for display so as to zoom into or out from a portion of the plot.

Abstract: An electronic image processing system 1 includes a large capacity store 2 having a source area 3 for storing data representing an initial image and a destination area 4 for storing data representing a modified image. A control processor 5 calculates transformation parameters and controls the transfer of portions of the initial image data to a high speed low capacity cache store 9. A spatial filter 10 effects transformations on the data in the cache store 9 and the thus modified image portion data is written to the destination area 4.

Abstract: In a system for detecting information stored upon a flexible magnetic media that includes a magnetic transducer for producing an analog signal representing stored binary data, comparator means for detecting positive and negative peaks of the analog signal, and voltage threshold means for providing a reference threshold voltage to the comparator which is a precise percentage of the voltage peaks of the analog signal, an improved magnetic recording detection pointer comprising a pulse width discriminator used to monitor the time per peak during which the analog signal exceeds the detection threshold as an indication of marginal data which can be used in conjunction with an error correction system to extend the overall system correction capability.