摘要:
In order to reproduce data scrambled in respective manners to recordable recording medium, it is necessary to take the step of discriminating if the reproduction signal comes from any recording medium before descrambling the data. Further, before doing the control, it is necessary to discriminate if the data is copy-permitted or copy-prohibited. To accomplish this process, a data recording and reproducing apparatus includes a first reproducing unit 1, a second reproducing unit 7 for receiving the data processed by the first reproducing unit and executing the next reproducing process about the data, a first authenticating unit 4 for authenticating the first reproducing unit 1, a second authenticating unit 8 positioned in correspondence with the first authenticating unit and for authenticating the second reproducing unit. The data recording and reproducing apparatus provides different authenticating unit (5, 6, 9, 10) from the first and the second authenticating units so that those authenticating units may execute the corresponding authentications before descrambling the data.
摘要:
An optical disk comprising compressed moving picture data and an optical disk reproduction apparatus each capable of easily effecting trick play such as high speed reproduction and a retrieval operation at a high speed. Additional information necessary for trick play is recorded in an arbitrary area of an optical disk such as a TOC (Table of Contents) or a leading sector (sector 0) of the disk, and a sector address is added to each sector. To conduct trick play, an I picture, a P picture and a B picture contained in a GOP layer inside a bit stream of compressed image data are extracted and reproduced in accordance with a reproduction speed by looking up a trick play table.
摘要:
A quick retry operation is possible by outputting an error flag pertaining to a sector after error correction processing of digital data. When an output of an error detection flag unit for a correction block indicates the existence of an uncorrectable error, the sectors are checked to see if the sectors corresponding to retrieved data include any error or not based on output from a sector error flag register B. When the sectors are judged as error, signals are retrieved again from a storage medium, re-stored in a memory, and an error correction processing is repeated again. The data such as that of P pictures or B pictures of MPEG which can be reproduced even with errors are output even when the error detection flag unit indicates the existence of the uncorrectable error. It enables identification of the sectors with the errors and simplifies the following operations pertaining to the error at a data receiving side by outputting the error flag along with the data.
摘要:
An optical disk recording thereon compressed moving picture data and an optical disk reproduction apparatus each capable of easily effecting trick play such as high speed reproduction and a retrieval operation at a high speed. Additional information necessary for trick play is recorded in an arbitrary area of an optical disk such as a TOC (Table of Contents) or a leading sector (sector 0) of the disk, and a sector address is added to each sector. To conduct trick play, an I picture, a P picture and a B picture contained in a GOP layer inside a bit stream of compressed image data are extracted and reproduced in accordance with a reproduction speed by looking up a trick play table.
摘要:
A digital signal reproduction device including a data strobe circuit high in margin against noise and rapid in recovery from dropout of data and a digital signal reproduction method performed in such device. The digital signal reproduction device includes a pair of data strobe circuits (4, 5) and a switching circuit (3) for selecting one of the outputs of the pair of data strobe circuits, and a circuit (1, 2) for generating from the received signal a signal to control the switching circuit (3). The data strobe circuits (4, 5) ensure high reliability of the received signal against noise and a short time from dropout of the received signal to acquisition of a reproduction clock. The data strobe circuit (4 or 5) is selectable which is suitable for the reproduction state of the reproduced signal.
摘要:
A rotary head type magnetic recording and reproducing apparatus for recording and reproducing an analog wide-band video signal, audio signal and compressed digital signal on the same recording medium. The modulated analog wide-band video signal or the narrow-band-converted compressed digital signal is recorded on two video tracks adjacent to each other on a magnetic tape (301) by magnetic heads (301a, 301b and 302a, 302b) on a rotary drum (300). In another arrangement in which the audio signals multiplexed in frequency are recorded on the audio track adjacent to the video tracks on the magnetic tape (310) by the magnetic heads (303a, 303b) and the decision circuit (264), by utilizing the signal reproduced from the audio track, determines whether the signal recorded on the video tracks is analog or digital, the input analog wide-band video signal is divided into signals of two channels by the recording-system analog signal processing circuit (57), those signals are recorded on the magnetic tape (60) in multi-track recording by a pair of magnetic heads (62a, 62b) and another pair of magnetic heads (62, 62d), the input audio signals are modulated by the FM modulator (15) and the QPSK modulator (16), and recorded in a deep-layer portion of another track between the video tracks. A compressed digital digital signal received by the antenna (1) is added with error correction codes by the recording-system digital signal processing circuit (5), and is modulated by the 16QAM modulator (6) so that the spectral components of the compressed digital signal does not enter the audio signal frequency band, and is recorded on said audio track superposed but in a deeper-layer portion of the tape by yet another pair of magnetic heads (64a, 64b).