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公开(公告)号：US4656514A
公开(公告)日：1987-04-07
申请号：US767646
申请日：1985-08-20
CPC分类号： H04N5/945
摘要： Apparatus for concealing errors in a digital television signal comprises delay elements for deriving a current sample value and a first group of the sample values spatially closest to the current sample value in the same frame of the television signal and delay elements for deriving from the preceding frame of the television signal a delayed sample value corresponding in position to the current sample value and a second group of sample values respectively corresponding in position to the sample values. The current sample value and the delayed sample value are checked for error, and subtractors check pairs of sample values corresponding in position in the current and preceding frames of the television signal for error, derive a measure of the difference in the levels of the sample values in each pair, and combine the results of these checks to provide an output signal which is a measure of the number of the errors and of the sum of the differences. A threshold device checks the output signal against a predetermined threshold level corresponding to an acceptably small number of errors and a relative low degree of movement in the part of a television picture corresponding to the groups of sample values, and a selector is operative, if the sample value is in error, the delayed sample value in not in error, and the output signal is below the predetermined level, to replace the current sample value by the delayed sample value for supply to an output, and, in all other cases, to supply the current sample value to the output.
摘要翻译： 用于隐藏数字电视信号中的错误的装置包括用于导出当前采样值的延迟元件和在电视信号的相同帧中空间上最接近当前采样值的采样值的第一组以及从前一帧导出的延迟元件 电视信号中的位置对应于当前采样值的延迟采样值和分别对应于采样值的位置的第二组采样值。 对当前采样值和延迟采样值进行错误检查，并且减法器检查对应于电视信号当前帧和前一帧中的位置的采样值对，以得出误差的电平差的度量 在每对中，并且将这些检查的结果组合以提供输出信号，其是误差数量和差异之和的量度。 阈值装置根据对应于可接受的少量错误的预定阈值水平检查输出信号，并且在与采样值组对应的电视图像的一部分中相对较低的运动程度，并且选择器可操作，如果 采样值误差，延迟采样值不出错，输出信号低于预定值，将当前采样值替换为延迟采样值供给输出，而在其他情况下， 将当前采样值提供给输出。
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公开(公告)号：US4819089A
公开(公告)日：1989-04-04
申请号：US125829
申请日：1987-11-25
申请人： James H. Wilkinson , John G. S. Ive
发明人： James H. Wilkinson , John G. S. Ive
IPC分类号： G11B20/12 , H04N5/7826 , H04N5/92 , H04N5/926 , G11B5/02
CPC分类号： H04N5/9268 , H04N5/78266 , H04N5/926
摘要： A digital video tape recorder comprises a head drum, four transducer heads mounted in pairs on the head drum for recording oblique tracks on a magnetic tape, a demultiplexer for distributing digital data to be recorded and corresponding to a video signal such that each field of the video signal is divided into 50-line segments, the digital data corresponding to each field are evenly distributed between all four of the heads for recording, and each track comprises a block of digital data relating to one 50-line segment and a block of digital data relating to another 50-line segment, the two blocks of digital data being separated by an edit gap.
摘要翻译： 一种数字录像机，包括一个头鼓，四个转头，成对安装在头鼓上，用于在磁带上记录斜轨道;多路分离器，用于分配要记录的数字数据，并与视频信号相对应， 视频信号被分成50行段，对应于每个场的数字数据被均匀地分布在用于记录的所有四个头之间，并且每个轨道包括与一个50行段和数字块相关的数字数据块 与另一个50行段相关的数据，两个数字数据块被编辑间隙分开。
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公开(公告)号：US4607367A
公开(公告)日：1986-08-19
申请号：US621226
申请日：1984-06-15
申请人： John G. S. Ive , James H. Wilkinson
发明人： John G. S. Ive , James H. Wilkinson
CPC分类号： H04N5/945 , G11B20/1809
摘要： A method of correcting errors in binary data which may represent a digital television signal, comprises assembling the data into a plurality of first blocks, each first block comprising a first plurality of, say sixty, data words and a second plurality of, say six, check words and further assembling the first blocks into arrays of first blocks and deriving first and second check blocks for each array of the first blocks. Each check word is derived in dependence on all the data words in the first block and each other check word in the first block. One check word may be derived by modulo-2 addition and the remaining check words may be derived by respective primitive polynomial generators. The first check block is derived by modulo-2 addition and the second check block is derived by a primitive polynomial generator.
摘要翻译： 一种校正可表示数字电视信号的二进制数据中的错误的方法，包括将数据组合成多个第一块，每个第一块包括第一多个，即六十个数据字，第二个多个，例如六个， 检查字，并将第一块进一步组装成第一块的阵列，并为第一块的每个阵列导出第一和第二校验块。 每个检查字根据第一个块中的所有数据字和第一个块中的每个其他检查字导出。 可以通过模2加法导出一个检查词，并且可以通过相应的基本多项式生成器来导出剩余的校验字。 第一个检验块通过模2加法导出，第二个检验块由原始多项式生成器导出。
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公开(公告)号：US4442520A
公开(公告)日：1984-04-10
申请号：US317295
申请日：1981-11-02
申请人： John G. S. Ive , Alan C. Thirlwall
发明人： John G. S. Ive , Alan C. Thirlwall
IPC分类号： H03M1/10 , H03K5/1252 , H03M13/00 , H04N9/79 , H04N9/804 , H04N9/808 , H04N9/82 , H04N9/87 , H04N9/888 , H04N11/04 , G06F11/08
CPC分类号： H04N9/8205 , H03K5/1252 , H04N9/87 , H04N9/888
摘要： Apparatus for example for use in achieving correct field framing on reproduction of a digital PAL television signal from a video tape recorder, by correcting errors in an input square-wave signal which signal alternates between first and second levels every four fields of the television signal, the apparatus comprising first and second similar counters to be supplied with the input signal so as to be enabled to count when the input signal is of the first and said second level respectively, means to detect errors in the input signal and thereupon to supply a signal to disable both the first and second counters, a clock pulse source for supplying a clock pulse signal of high frequency relative to the frequency of the input signal to the first and second counter, and a bistable circuit arranged to be triggered to a first stable condition by an overflow signal from the first counter and to a second stable condition by an overflow signal from the second counter, whereby the bistable circuit supplies a corrected replica of the input signal.
摘要翻译： 例如，用于通过校正输入方波信号中的错误来校正来自录像机的数字PAL电视信号的再现的正确的场成帧的装置，该信号在电视信号的每四个场的第一和第二电平之间交替， 所述装置包括第一和第二相似的计数器，以分别提供输入信号以便能够对输入信号是否处于第一和第二电平进行计数，这意味着检测输入信号中的错误，从而提供信号 禁用第一和第二计数器的时钟脉冲源，用于向第一和第二计数器提供相对于输入信号的频率的高频的时钟脉冲信号的时钟脉冲源，以及被布置成被触发到第一稳定条件的双稳态电路 通过来自第一计数器的溢出信号和来自第二计数器的溢出信号到第二稳定状态，由此双稳态电路 提供输入信号的校正副本。
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公开(公告)号：US4400810A
公开(公告)日：1983-08-23
申请号：US257393
申请日：1981-04-24
申请人： John G. S. Ive
发明人： John G. S. Ive
IPC分类号： H03M13/00 , G11B20/18 , H03M13/27 , H04N1/40 , H04N5/92 , H04N5/926 , H04N5/945 , H04N7/12 , H04N19/89 , G06F11/10
CPC分类号： G11B20/1813 , H04N19/89 , H04N5/926 , H04N5/945
摘要： A method of processing binary data, which is preferably a digital television signal, comprises dividing the data into blocks of ten 8-bit words, deriving an 8-bit parity word each digit of which is a parity digit for the corresponding digits of the ten words, deriving an 8-bit check word by binary summing the ten words and forming the check word as the eight least significant bits of the resulting binary sum, subjecting to further processing, for example by magnetic recording and reproduction, the block of words including the parity word and the check word, and thereafter checking the parity word and the check word to reveal errors occuring in the ten words during the further processing.
摘要翻译： 一种处理二进制数据的方法，其优选地是数字电视信号，包括将数据划分成十个8位字的块，得到每个数字为8位奇偶校验字的8位奇偶校验位，用于十位相应位数的奇偶校验位 字，通过将十个字进行二进制求和来形成8位校验字，并将校验字形成为所得到的二进制和的八个最低有效位，进行例如通过磁记录和再现的进一步处理，包括 奇偶校验字和检查字，然后检查奇偶校验字和校验字，以显示在进一步处理期间在十个字中发生的错误。
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公开(公告)号：US4855843A
公开(公告)日：1989-08-08
申请号：US83903
申请日：1987-08-06
申请人： John G. S. Ive
发明人： John G. S. Ive
CPC分类号： H04N5/782 , G11B15/1875 , G11B27/005 , G11B5/0086 , H04N5/783 , H04N5/937 , H04N9/802 , G11B2220/90
摘要： A method of recording and reproducing a digital video signal, the method comprising recording the video signal in oblique tracks on a magnetic tape using a four-head digital video tape recorder, the four heads being arranged in two head pairs disposed on diametrically opposite sides of a rotary head drum, and the video data relating to each field being distributed evenly between the four heads for recording, each oblique track comprising two half-tracks separated by a central gap in which audio data may be recorded, and each field occupying a plurality of successively recorded pairs of half-tracks with each field boundary located at a central gap, and reproducing the video signal at a speed different from the normal reproduction speed using dynamic tracking by successively reproducing two half-tracks from the first part of a first pair of adjacent oblique tracks, then jumping to reproduce two half-tracks from the second part of a second pair of adjacent oblique tracks adjacent to the first pair and so on until all the data of one field has been reproduced, and then jumping to another field.
摘要翻译： 一种记录和再现数字视频信号的方法，所述方法包括使用四头数字录像机在磁带上将倾斜轨道中的视频信号记录在磁头上，四个磁头布置成两个头对， 旋转磁头鼓，并且与每个磁场相关的视频数据均匀分布在用于记录的四个磁头之间，每个倾斜轨道包括由其中可记录音频数据的中心间隙分开的两个半磁道，并且每个磁场占据多个 连续记录的每个场边界位于中心间隙的半轨迹对，并且使用动态跟踪以与正常再现速度不同的速度再现视频信号，通过从第一对的第一部分连续再现两个半轨道 然后从邻近f的第二对相邻倾斜轨道的第二部分跳跃再生两个半轨迹 第一对等等，直到一个字段的所有数据都被再现，然后跳转到另一个字段。
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公开(公告)号：US4246569A
公开(公告)日：1981-01-20
申请号：US68176
申请日：1979-08-20
CPC分类号： G06F11/076 , H04N7/56
摘要： A circuit for monitoring digital data comprises a shift register for receiving the data to be monitored, the outputs of the shift register being fed either directly to the inputs of memory devices or via controllable gates. The memories are programmed to detect the number of logical `ones` present in the shift register, and the detected number is compared with a reference to determine whether the data should be accepted or rejected. In one mode of operation, the controllable gates alter the inputs to the memories such that they are all the same when the correct data is in the shift register. In another mode of operation, the gates supply the memories with unaltered data and the circuit can detect errors because the data is coded in such a manner that each block of data should contain the same number of digits and the same number of logical `ones`.
摘要翻译： 用于监视数字数据的电路包括用于接收要监视的数据的移位寄存器，移位寄存器的输出直接馈送到存储器件的输入端或通过可控制的栅极。 存储器被编程为检测移位寄存器中存在的逻辑“1”的数量，并将检测到的数量与参考值进行比较以确定数据是否应被接受或拒绝。 在一种操作模式中，可控制的门将存储器的输入改变成当正确的数据在移位寄存器中时它们都是相同的。 在另一种操作模式中，门为未改变的数据提供存储器，并且电路可以检测错误，因为数据被编码，使得每个数据块都应该包含相同数量的数字和相同数目的逻辑“1” 。
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公开(公告)号：US4549298A
公开(公告)日：1985-10-22
申请号：US508189
申请日：1983-06-27
申请人： David M. Creed , John G. S. Ive
发明人： David M. Creed , John G. S. Ive
CPC分类号： G11B20/1809
摘要： A method of detecting and correcting errors in digital audio signals comprises assembling digital data words each of which corresponds to a digital audio signal representing an analog audio sample into units of six data words, assembling with each unit six redundant words derived by exclusive-OR operations on the data word in each row and each column of the unit, assembling the data words and redundant words into sub-blocks and adding cyclic redundancy check code words to the sub-block, recording and reproducing each sub-block, after reproduction using the code words of each sub-block to set the logic state of error flags that have been added to each word in the sub-block, re-forming the units and assembling with each reproduced unit horizontal and vertical syndromes derived by exclusive-OR operations on the data words and redundant words in each row in each column of the unit, comparing the horizontal and vertical syndromes and resetting the logic state of the error flags in dependence on this comparison, deriving further horizontal syndromes by exclusive-OR operations on the data words and redundant words in each row of the reproduced unit and where there is only a single word in a row flagged as being in error, correcting that error word using the further horizontal syndrome, and deriving further vertical syndromes by exclusive-Or operations on the data words and the redundant word in each column of the reproduced unit and where there is only a single word in that column in error, correcting that error word using the further vertical syndrome.
摘要翻译： 一种检测和纠正数字音频信号中的错误的方法包括将每个数字数据字对应于表示模拟音频样本的数字音频信号组合为六个数据字的单位，与每个单元组合六个通过异或运算导出的冗余字 在单元的每行和每列中的数据字上，将数据字和冗余字组合成子块，并将循环冗余校验码字添加到子块，记录和再现每个子块，在使用 每个子块的码字设置已被添加到子块中的每个字的错误标志的逻辑状态，重新形成单元并且与每个再现单元组合，通过异或运算导出的水平和垂直综合征 在单位的每一列的每一行中的数据字和冗余字，比较水平和垂直综合征，并重新设置依赖于错误标志的逻辑状态 在该比较中，通过异或运算对再现单元的每行中的数据字和冗余字导出进一步的水平综合征，并且其中标记为错误的行中只有一个单词被纠正，使用 进一步的水平综合征，并且通过对再现单元的每列中的数据字和冗余字的异或运算导出进一步的垂直综合征，并且其中该列中只有一个单词在错误中，使用 进一步垂直综合征。
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公开(公告)号：US4486780A
公开(公告)日：1984-12-04
申请号：US226861
申请日：1981-01-21
申请人： John G. S. Ive
发明人： John G. S. Ive
CPC分类号： H04N5/935 , G11B20/18 , G11B27/107 , G11B27/3027 , G11B2220/90
摘要： A sequential data block address processing circuit for deriving address signals in dependence on incoming data which comprises sequential blocks of data each including an address signal representing a number, the numbers changing cyclically from block to block, for example where the incoming data is derived from a video tape recorder and represents video information comprising sequential blocks of data each representing a horizontal line scan of video information and each including a line address signal, the circuit comprising an address counter to generate output address signals corresponding to the incoming address signals and likewise changing cyclically from block to block under control of a signal derived from an oscillator and supplied by way of a counter operating as a frequency divider, and an arrangement formed by three latch circuits, an add and delay device, a line address comparator, and a counter for synchronizing the output address signals relative to the incoming address signals only when a predetermined plurality of the incoming address signals have been correctly received.
摘要翻译： 一种顺序数据块地址处理电路，用于根据输入数据导出地址信号，该输入数据包括顺序的数据块，每个数据块包括表示一个数字的地址信号，该数字从块到块周期性地变化，例如输入数据从 视频磁带录像机，并且代表包括顺序数据块的视频信息，每个数据块表示视频信息的水平行扫描，并且每个数据块包括行地址信号，该电路包括一个地址计数器，以产生对应于输入地址信号的输出地址信号， 在由振荡器产生的信号的控制下，通过作为分频器的计数器提供的块，以及由三个锁存电路，一个加法和延迟装置，一个行地址比较器和一个计数器 输出地址信号相对于输入地址进行同步 仅当预定的多个输入地址信号已被正确接收时才产生信号。
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公开(公告)号：US4316223A
公开(公告)日：1982-02-16
申请号：US128861
申请日：1980-03-10
申请人： John L. E. Baldwin , John G. S. Ive
发明人： John L. E. Baldwin , John G. S. Ive
CPC分类号： H04N5/926 , G11B20/1809
摘要： Digital recording and reproducing apparatus is disclosed for recording digital signals in such a manner as to conceal errors contained therein, including a write address generator for storing incoming digital signals in a first sequence in a memory, and a read address generator for causing the signals to be read out from the memory in a second sequence different from the first sequence. A control device selectively connects the write address generator and the read address generator sequentially to the memory, whereby the digital signals read out from the memory may be recorded on a recording medium.
摘要翻译： 公开了用于以隐藏其中包含的错误的方式记录数字信号的数字记录和再现装置，包括用于以存储器中的第一序列存储输入数字信号的写入地址发生器，以及用于使信号 以与第一序列不同的第二序列从存储器中读出。 控制装置选择性地将写入地址发生器和读取地址生成器顺序地连接到存储器，从而从存储器读出的数字信号可以被记录在记录介质上。
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