Abstract: A serial data coding system is described in which a state machine (FIG. 5) is provided having a plurality of branching hierarchies N, N+1 of states each corresponding to a different decoding table. Depending upon each received bit of serial data, the state machine moves through these branching hierarchies of states until states 88 corresponding to valid codes are reached whereupon a valid code is decoded and the state machine reset to the start of that branching hierarchy. If it is desired to move between branching hierarchies, then an internal table selecting word is inserted into the stream of serial data to move the state machine into a table incrementing state 90 where a jump to another branching hierarchy of states may be made. In order to cope with an externally applied switching signal Y/C for switching the state machine between branching hierarchies, the state machine is first moved into one of a plurality of transfer states A, C, D etc.

Abstract: A digital video tape recording/playback system having a plurality of recording heads (A, B, C, D) on a rotating head mechanism 94 for recording slanting tracks 108 which extend diagonally across a tape 82 provides processing of video signals in a plurality of data processing channels with selective connection of the data processing channels to the recording heads such that data from a plurality of data processing channels are stored in respective portions of a slanting track (A+/A-; B+/B-; C+/C-; D+/D-). The data in each data processing channel and recorded in each track portion is sampled with a substantially even distribution over a field of video signals to provide for effective concealment of recording/playback errors. Preferably, two data processing channels are recorded on each track, the respective portions being located in upper and lower portions of the tape, respectively.

Abstract: An image data processing apparatus generates output data representing an image in a spatial domain from a plurality of sets of input data, each representing in a spatial frequency domain a sub sampled version of the image in the spatial domain. An error detector detects any erroneous parts of the plurality of sets of input data in the spatial frequency domain. Each of the plurality of sets of input data is transformed from the spatial frequency domain into a sub sampled version of the image in the spatial domain. Any parts of the sub sampled versions that are dependent upon an erroneous part of a set of input data are interpolated from one or more spatially adjacent parts of one or more other sub sampled versions. The sub sampled versions are combined to form the output data.

Abstract: Data formatting apparatus for formatting variable bit length data words into successive fixed bit length data words comprises an N-bit circular buffer comprising a plurality of concatenated buffer sections, each buffer section having the same bit length as one of the fixed bit length data words. A modulo-N counter generates a count of the cumulative length of received variable bit length data words. Each received variable bit length data word is stored in the N-bit circular buffer at a bit position dependent on the count signal, and, in response to a detection that data has been stored in all of the bits of that buffer section, the stored data from that buffer section is output as a fixed bit length data word.

Abstract: A serial data decoder is described employing a bank of parallel primary Huffman decoders 70 each operating to decode a stream of variable length code words with embedded control code words into a stream of fixed length index values. The fixed length index values are fed to a secondary decoder which operates under control of the fixed length index values representing control code words to decode the fixed length index values representing the variable length code words into output data.

Abstract: Spatial demultiplexing of data (e.g. video data) is employed in a digital recorder comprising four heads (A, B, C, D) organized as 2 groups (A/C; B/D) each of 2 heads, whereby a field of data comprising a plurality of lines is spatially demultiplexed into i.times.4 data processing channels such that each data processing channel receives a different set of pixels including alternating pixels on every fourth line. The technique finds particular application to the recording of video data in compressed form as the distribution of the pixels to the data processing channels enables efficient compression to be achieved. The video data can be decorrelated before compression. The spatial demultiplexing is then performed on the decorrelated data.

Abstract: A system for integrating film material with a digital video signal employs a film scanner to produce a digital video signal from the source film, and a post production system for combining with that signal the input digital video signal. Motion interpolated temporal compensation is employed at stages of frame rate conversion.

Abstract: An input digital video signal representing a series of input frames is processed to produce an output digital video signal representing a series of output frames with an increased motion blur effect. For each output frame at least one intermediate field or frame is produced by motion compensated temporal interpolation between a pair of the input frames. Each output frame is then produced by combining the intermediate field or frame with at least one further intermediate field or frame and/or with one of the respective input frames so that the output frame has an increased motion blur characteristic compared with that of the input frames. Using motion compensated temporal interpolation, a change in frame rate can also be produced as between the input frames and the output frames.

Abstract: A system for integrating film material with a digital video signal employs a film scanner to produce a digital video signal from the source film, and a post production system for combining with that signal the input digital video signal. Motion interpolated temporal compensation is employed at stages of frame rate conversion.

Abstract: Method of integrating 30 or 60 frame/s format material and 60 field/s 2:1 interlace scan format digital video signal to produce a 60 field/s 2:1 interlace scan format digital video signal by producing a progressive scan format digital video signal from the format material, converting the progressive scan format digital video signal to a 60 field/s 2:1 interlace scan format digital video signal and combining the converted signal with the 60 field/s interlace scan format digital video signal.

Abstract: Image data multiplexing apparatus for multiplexing digital luminance and chrominance data of a representation of an image into multiplexed data blocks of a predetermined length, along with a corresponding demultiplexing apparatus, is described. Each of the multiplexed data blocks comprises a luminance data section comprising luminance data from a portion of the representation, a chrominance data section comprising chrominance data from the portion of the representation, a portion address indicative of the position in the representation of the portion, and a block offset pointer indicative of the position in the multiplexed data block of the boundary between the luminance data section and the chrominance data section.

Abstract: An input digital video signal is converted to an output digital video signal having a different frame rate and a different number of pixel lines per frame. A first series of progressive scan format frames is formed from the input signal. Then a second series of frames is formed from the first series of frames using motion compensated temporal interpolation between successive frames of the first series in producing at least some of the frames of the second series so as to provide the difference in frame rate. Before or after the second series of frames is formed, vertical spatial interpolation is performed so as to provide the difference in the number of pixel lines per frame.

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, further motion vectors are selected for assignment to those of the blocks for which less than a predetermined plurality of good motion vectors are derived as a result of the comparison, by ranking all the good, non-stationary motion vectors derived for the field or frame in order of frequency of occurrence, and selecting those motion vectors which occur most frequently, unless they fall within a predetermined window of pixel motion of a motion vector already selected.

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 succeeding 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 respective correlation surface is generated for blocks in the first field or frame, the correlation surface representing the difference between the content of the 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 shape of that part of the correlation surface which represents differences less than a threshold level is determined, and the comparison is varied in dependence on the shape.

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 succeeding field or frame of the video signal for deriving motion vectors representing the motion of the contact 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 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 magnitudes of the differences represented by the correlation surface are weighted if a preliminary determination of the correlation surface fails to reveal a clear minimum difference.

Abstract: Apparatus for converting a video signal to a photographic film image comprises a television standards converter for deriving from an input video signal, which may be a high definition video signal, a motion compensated digital video signal corresponding to 24 progressive scan frames per second, a video signal recorder for recording the digital video signal, a digital-to-analog converter for converting the digital video signal after reproduction to an analog video signal corresponding to 24 progressive scan frames per second, and an electron beam recorder to which the analog video signal is applied to record the content of the analog video signal on photographic film.

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 a plurality of motion vectors representing the motin of the content of respective blocks between the first field or frame and the following field or frame, a respective motion vector is derived, from the plurality of motion vectors, for each pixel in each block of each input field or frame by luminance matching each pixel in an input field or frame with the pixels, in the previous and following input field or frame, pointed to by said plurality of motion vectors, and when there is a luminance mis-match between a pixel in an input field or frame and all the pixels, in the respective previous or following input field or frame, pointed to by the plurality of motion vectors, the respective motion vector is derived by luminance matching each pixel in an input field or frame with the pi

Abstract: In, for example, a motion compensated video standard 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 a plurality of motion vectors representing the motion of the content of respective blocks between the first field or frame and the following field or frame; firstly a respective motion vector is derived, from the plurality of motion vectors, for each pixel in each block of each input field or frame by luminance matching each pixel in an input field or frame with the pixel pointed to by the respective motion vectors in the previous and following input fields or frames, and secondly, a respective motion vector is derived for each pixel in each block of each output field or frame by comparing the motion vectors so derived for the two input fields or frames which are temporarily nearest to the output field or frame.

Abstract: In, for example, a motion compensated video standards converter blocks in a first field or frame of a video signal are each compared in a gate array 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, a correlation surface is generated for respective blocks in the first field or frame, the correlation surface representing the difference between the content of the 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, and the motion vectors are derived in dependence on a minimum in the correlation surface.

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 next succeeding 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 next field or frame, the blocks adjacent to a border region of the field or frame are assigned motion vectors selected from the motion vectors which have been derived for those of the blocks which are adjacent to the block under consideration and are not in the border region.