Abstract: An image data recording and transmission system is described in which a data compressor 76 decorrelates input image data into sub band component data, a data recorder 78 stores the sub band data, a data decompressor 80 decompresses data read from the data recorder and a transmission signal generator 82 produces a bandwidth limited transmission signal from the decompressed data. The combined action of a data sequencer 18, a quantizer 114 and an entropy encoder 20 within the data compressor act to remove from the data stream that information corresponding to frequencies not transmittable with the bandwidth limited transmission signal (e.g. PAL or NTSC) subsequently produced by a transmission signal generator 82. Accordingly, the data recorder need not use storage capacity recording data which cannot be used by the transmission signal generator.

Abstract: An image capture apparatus (eg. a video camera) for producing video image signals includes an image sensor for producing image signals having signal values representative of radiation intensity incident on respective positions of the sensor. The apparatus is able to identify an area of the sensor at which the incident intensity exceeds a predetermined intensity and to cause a stepped reduction in the image signal values corresponding to said area. The apparatus enables a range of intensity levels above a predetermined maximum to be translated or shifted to within a range which can be accommodated, for example by a broadcast television system, in a manner equivalent to applying a negative pedestal to that range of intensity levels.

Abstract: A digital video signal is compressed by spatial sub-band filtering to form data sets constituting respective sub-bands of the two-dimensional spatial frequency domain. The data sets for a field or frame are stored. A first sequencer controls writing, in accordance with a desired sequence, of the stored data to a quantizer in which they are quantized in accordance with respective values, those values being such that the amount of quantization of at least a data set constituting a sub-band to which dc luminance information of the signal is at least predominantly confined is less than the average of the amounts of quantization of the remaining data sets. The quantized data sets are then encoded in an entropy encoder which has a first coding portion for coding quantized data representative of dc luminance information and a second coding portion for coding quantized data representative of ac luminance information.

Abstract: To enable a digital composite color video signal (NTSC or PAL) to be compressed directly, that is without dividing it into its components and compressing the components separately, the digital composite color video signal is decorrelated, for example by spatial sub-band filtering, to form data sets, for example sub-bands, representing dc luminance information, ac luminance information and dc chrominance information. The data sets are then quantized in accordance with respective quantization values from a quantization matrix, those quantization values being such that the amount of quantization of each of some of the data sets to which the dc luminance information and the dc chrominance information is at least predominantly confined is less than the average of the amounts of quantization of the remaining data sets. At least some of the quantized data sets are then entropy encoded.

Abstract: A digital video signal is real-time converted from a conventional definition format, such as 525 lines, 60 field/s, 2:1 interlace, with a 4:3 aspect ratio and 720.times.486 active pixels, to a high definition format, such as 1125 lines, 60 field/s, 2:1 interlace, with a 16:9 aspect ratio and 1920.times.1035 active pixels by writing the pixels of the conventional definition fields to alternate field stores at the conventional definition format pixel rate; by formed intermediate frames in the high definition format by reading pixels from the field store which is not being written at the high definition pixel rate and adding background pixel data between the lines of the read pixels and between the fields of the read pixels; by translating the pixels of the intermediate image, if necessary; and by expanding the image so that the originating pixel data extends across the whole frame in at least one direction.

Abstract: In, for example, a motion compensated video standards converter wherein blocks in a first field or frame of a video signal are each compared with a plurality of blocks in the following field or frame of the video signal for deriving motion vectors representing the motion of the content of respective blocks between the first field or frame and the following field or frame, and wherein a correlation surface is generated for each block in the first field or frame, the correlation surface representing the difference between the content of the first block in the first field or frame and the content of each block in the following field or frame with which it has been compared; the minimum difference represented by the correlation surface and differing from the next smallest difference represented by the correlation surface by more than a predetermined threshold value is found to derive a motion vector, the number of motion vectors so derived is averaged (62) over a predetermined number of fields or frames, and the

Abstract: A video camera control apparatus (10') includes a respective remote control panel (14) and a respective camera control unit (16) for each of several video cameras (12) to be controlled by the apparatus. Each remote control panel (14) is connected to the associated camera control unit (16) by a respective bus (18) whereby technical operational control of each camera can be effected at the associated remote control panel (14). A respective interface unit (30) is connected in the bus (18) between each remote control panel (14) and the associated camera control unit (16). A master control unit (34) connected to all of the interface units (30) is capable of communicating with any selected one of the camera control units (16) via the associated interface unit (30) to enable technical operational control of any selected one of the cameras (12) to be effected at the master control unit.

Abstract: An image signal processing apparatus has an address generator that generates addresses for successive words of a digital input signal representing an input image to be manipulated. A computation circuit monitors the addresses for successive word sets which each comprise first and second words relatively horizontally spaced in the input image and a third word aligned vertically with the second word, and computes from each set both horizontal and vertical local scaling factors representing the extent of compression in the horizontal and vertical directions of a corresponding local area of the manipulated image. A bandwidth controller is responsive to the successive scaling factors to vary the horizontal and vertical bandwidths of a digital filter which two-dimensionally filters the input image, thereby to minimize aliasing that would be caused by the manipulation of the local areas.

Abstract: Apparatus for processing a video signal derived by single frame animation for subsequent merging with live action material, comprises a motion vector estimator (11) for deriving motion vectors in dependence on motion in the picture sequence represented by the video signal, and an interpolator (12) and associated circuits (14 to 16) for blurring the images represented by the video signal of objects in the picture sequence so determined as being in motion in dependence on the motion vectors.

Abstract: Apparatus for photographic movie film to video signal conversion comprises a movie film to video conversion apparatus such as a telecine (11) in which the film (1) is aligned frame by frame to derive a video signal, and a video signal processor (16), such as a digital video effects apparatus (12), to process the derived video signal by reference to registration features (2) of the film (1), such as L-shaped registration marks (2) exposed thereon adjacent to each frame (3) of the film (1), to obtain more accurate frame alignment of the video signal.

Abstract: Apparatus for converting, for example, 24 Hz 1:1 format film to, for example, a 60 Hz 2:1 interlace format video signal comprises a converter (12) for transferring 24 Hz 1:1 format film material to a 60 Hz 2:1 interlace format video signal using 3 2 3 2 pull down, and a coder (13) associated with the converter (12) for associating a 10-field sequence identifier with the video signal. The 10-field sequence identifier is used to maintain identification of the phantom fields and the field sequence through subsequent processing, and in particular to control motion processing.

Abstract: Video signal processing apparatus, for example a television standards converter (12), for motion adaptive or motion compensated processing a video signal in dependence on inter-field or inter-frame information, comprises a reader (21) for reading scene discontinuity information relating to the video signal, which may be expressed in time codes, from a recording medium such as a magnetic disc, the apparatus being controlled in dependence on the read information to cause the processing of the video signal to change to being dependent on intra-field or intra-frame information at a scene discontinuity.

Abstract: A motion compensated video standards converter comprises a block matcher (3) for deriving a plurality of motion vectors for each pixel of each field or frame of an output standards-converted video signal, the motion vectors representing motion between successive fields or frames of an input video signal from which the output video signal is to be derived by motion compensated interpolation, a circuit (25) for testing each said motion vector by deriving the sum of absolute luminance differences of corresponding pixels in blocks of pixels in the two fields or frames of said input video signal temporarily nearest a field or frame of said output video signal, which blocks are pointed to by the motion vector under test, a circuit (26 to 28) for center-weighting said sum of absolute luminance differences if the magnitude of said motion vector under test is less than a predetermined value, and a selector (29) for selecting from said plurality of motion vectors, the motion vector which results in the minimum said sum

Abstract: Dropout is compensated in a video signal that has samples comprising respective different color information components in alternate lines and samples comprising luminance information time multiplexed with the color samples in each line. Adders (78, 82) average first and second sample (S1, S2) positioned one line after and one line before a central reference sample SR to produce a first averaged sample SA1, and third and fourth samples (S3, S4) positioned two lines after and two lines before the sample SR to produce a second averaged sample SA2. Gating means (48 to 60) outputs any one of the sample SR, the averaged samples and the first to fourth samples.