Abstract: A brushless sensorless motor driving circuit for driving a motor having a rotatable rotor and a plurality of excitation coils in which a motor starting mode may be smoothly switched to a normal driving mode so as to reduce a fluctuation in a starting time. The sensorless motor driving circuit includes a detection circuit for detecting a generated induction voltage from the excitation coils; a phase-locked loop circuit for generating a clock pulse; a delay pulse generating circuit for generating a delay pulse based on the clock pulse; a switching signal generating circuit for generating conduction switching signals in accordance with the delay pulse and an output signal from the detection circuit for causing an excitation pattern of the excitation coil to be switched to another excitation pattern; and starting pulse inserting circuits for inserting a starting pulse based on the clock pulse in the detection circuit when the induction voltage is not generated.

Abstract: A tape cartridge comprises a base plate, a pair of tape reels rotatably supported by a pair of upstanding reel shafts which shafts are supported on the base plate, and a magnetic tape wound on the tape reels wherein a plurality of tape guides are provided to define a tape travel path. The base plate is formed with an aluminum-alloy plate with a hard protective film on both faces of the aluminum-alloy plate and small impressions in the hard protective film for elimination of residual strain. The hard protective film is formed by an anodic oxidation coating. In order to eliminate residual stress or strain existing in the base plate formed by a punching operation, each of the small impressions is formed by impressing the hard protective film to a depth within a thickness of the hard protective film or to a depth within a permissible limit of deformation (elongation) of the hard protective film.

Abstract: An optical disk having a diameter less than 140 mm and, a thickness of 1.2 mm.+-.0.1 mm, with a plurality of record tracks having data recorded thereon as embossed pits representing information and exhibiting a track pitch in the range between 0.646 .mu.m and 1.05 .mu.m; with the tracks being divided into a lead-in area, a program area and a lead-out area. The data includes table of contents (TOC) information recorded in a plurality of sectors in at least one TOC track and user information recorded in a plurality of sectors in user tracks; with the TOC information including addresses of start sectors recorded in the user tracks. The data (both user and TOC information) is encoded in a long distance error correction code having at least eight parity symbols, and is run length limited (RLL) modulated.

Abstract: A picture type identifier, indicating one of intra-picture coding (an I-picture), forward or backward predictive coding (a P-picture) and bi-directionally predictive coding (a B-picture), is included with a picture signal when the signal is encoded and when the signal is decoded. Each of initial and subsequent encoding and decoding is a function of the included picture type.

Abstract: A digital signal decoding apparatus for preventing errors which cannot be corrected sufficiently by error correction from reflecting on a decoded signal. An uncorrectable error part of a digital signal or a data part including the error part is replaced with a special code including a synchronous code, and is output to decoding means. Because the decoding means capable of identifying the synchronous code can also identify the special code, a proper error processing can be executed by confirming the presence of errors at the time of decoding. Therefore, by using the decoding means, it is possible to prevent errors which cannot be sufficiently corrected from reflecting on a decoded signal.

Abstract: The present invention is intended to enable smooth reverse regeneration of image data while minimizing a large-sized and expensive configuration of an apparatus according to the present invention. Compression-coded image data recorded on an optical disc 1 is regenerated and stored in a ring buffer 5. Image data stored in the ring buffer 5 is decoded in a decoding part 20. A control circuit 21 controls to store the image data necessary for decoding in the ring buffer 5 in terms of, for example, one GOP and repeatedly read the image data from the ring buffer 5 when it is necessary for reverse regeneration if reverse regeneration is commanded.

Abstract: On tape carrying a mixture of a static image recording portion and a dynamic image recording portion, ID (identification) signals are recorded to specify only a specific static image for retrieval. During image recording, the PP (Photo/Picture) ID signal indicative of the static image recording portion is automatically recorded on the static image recording portion for a sufficiently long duration to allow its detection during quick search. When a desired static image is determined on the screen, the INDEX ID signal indicative of the static image is subsequently implanted only in the static image recording portion. Thus, the desired static image can be retrieved by first searching the PP ID signal quickly to locate the static image recording portion and then searching the INDEX ID signal in the static image recording portion. These two ID signals can also be subsequently implanted in the dynamic image recording portion to retrieve any one frame image.

Abstract: In a picture encoding and decoding method and apparatus, an object contour can be chain coded precisely even in the case where noise exists in the vicinity of object contour, and the object contour branched off can be coded with small quantity of codes. In the case where the branched part occurs in a feature point chain, by multiplexing branch code D1 to chain codes S23 and S22 and expressing as a tree structured feature point chain including the branch part of the object contour, an increase in number of chains can be controlled and the efficient chain coding can be conducted. Moreover, since the terminal branch chains having no branch point in the chain become the objects of thresholding, only noise elements can be effectively eliminated without cutting off the feature point chain showing the object contours.

Abstract: A recording apparatus, recording/reproducing apparatus or a reproducing apparatus for digital video signals, in which ATV signals, for example, recorded directly on the recording medium, may be easily reproduced with plural varying playback speeds, and in which a playback picture output with spontaneous motion may be achieved even during low varying playback speed. A first area for directly recording the input area, a plurality of second areas for recording data of the input data obtained on intra-picture coding as first data for varying-speed reproduction and a plurality of third areas for recording the motion vector of data of the input data obtained on inter-picture predictive coding as second data for varying-speed reproduction, are provided in each track of the recording medium. The first data and the second data for varying-speed reproduction are repeatedly recorded on a number of tracks of the same azimuth corresponding to the number of speed multiples of the maximum varying playback speed.

Abstract: A method for reducing the blank spaces resulting from the storage of multiple data blocks on a storage medium. In one embodiment, data is stored on a magnetic tape. Data to be written to the tape is partitioned into user data blocks and management data blocks, the user data blocks being written on the tape sequentially in a longitudinal direction in tracks along the tape, and the management data blocks being written in tracks on the tape sequentially in a longitudinal direction that is opposite the write direction of the user data blocks. Writing the user data and management data in directions that are inversely related allows the amount of wasted storage space to be reduced.

Abstract: In a video tape recorder capable of recording information for a long time, first and second rotary heads are angularly spaced by 180.degree. and are arranged without a step between their respective planes of rotation. In a frame recording operation, an odd field of a frame is recorded by the first head in a first track on the tape while the latter is in a stationary condition and an even field of the same frame is stored in a field memory, whereupon, the tape is intermittently driven a distance corresponding to the track pitch and then, while the tape is again in its stationary condition, the stored even field is read from the memory and recorded by the second head in a second track adjacent the first track.

Abstract: Apparatus and method for reproducing data from a CD-ROM at a constant angular velocity and for recording and reproducing data to and from a magneto-optical compact disc (CD-MO) at a constant angular velocity. Data reproduced from the CD-ROM is demodulated in accordance with an amount of reproduction time of a sync signal contained in the reproduced data. The clock rate of data to be recorded to or reproduced from the CD-MO is determined in accordance with the position or zone on the CD-MO at which the data is to be recorded or from which it is reproduced. The position or zone may be identified by address data which is reproduced from the CD-MO. In addition, a constant rotational velocity of the CD-MO is maintained by measuring an amount of reproduction time of the address data and varying the rotational velocity of the CD-MO in accordance with the measured reproduction time.

Abstract: A method and an apparatus arranged to record data at a higher density. Learning data generated by a learning data generating circuit is recorded on a disc and is actually reproduced by a player to measure inter-code interference in the learning data by an inter-code interference measuring section. In a pre-emphasis correction value calculating section, a pre-emphasis correction value corresponding to the measured inter-code interference is calculated. The result of this calculation is recorded as a table in a ROM of a recording edge position calculating circuit. The recording edge position calculating circuit processes recording data output from an information source in accordance with the table recorded in this ROM.

Abstract: Digital signal processing (e.g. filtering) apparatus comprises pipelined digital signal processing means for generating each output sample of an output digital signal from input samples of an input digital signal by combining the input samples with a plurality of subsets of a set of filter coefficients associated with that output sample during a respective plurality of sample periods of the input digital signal; and coefficient generating means for supplying sets of filter coefficients to the signal processing means in response to the current state of a filter control signal. The coefficient generating means is operable to supply the plurality of subsets of each set of filter coefficients to the signal processing means during the respective plurality of sample periods of the input digital signal.

Abstract: In a first guide unit the plural number of electrodes are provided facing the edge of a movie film containing a plurality of perforations formed along the longitudinal direction of the movie film, in a second guide unit a band shaped conducting material is provided facing the electrodes having the movie film between, and each stop position with respect to window holes is detected based on the amount of change of each electrostatic capacity changing depending on the displacement rate from each stop position of a plurality of condensers which are formed making each electrode and conducting material as a pole plate respectively and making the thickness of the movie film as the distance of pole plates. Therefore, a film position detection device, a film image display device and a movie film recording device capable of further improving the movie film position detection accuracy can be realized with the simple construction.

Abstract: A method and an apparatus for reproducing digital video signals in which every one-frame data of the digital video signals are recorded on n tracks of a recording medium by an inclined azimuth recording system are varying speed reproduced by a rotary head having n heads with a varying playback speed such that A=a(t.multidot.m.+-.1)/n, where a is a constant equal to 1 or 2 and m is a constant which is an integer other than 0. A picture corresponding to the digital video signals read out with the varying playback speed S is displayed on the screen. In this manner, non-continuous lines caused by temporal difference in neighboring macro-blocks during varying speed reproduction may be rendered less obtrusive for improving the picture quality of the varying speed reproduced picture.

Abstract: A disk storage medium, for example, a magneto-optical compact disk, includes a plurality of data areas that have data stored therein and a plurality of address areas each associated with a respective data area and that have address data stored therein. The data in each of the data areas are stored at respectively different clock rates, and all of the address data in all of the address areas are stored at the same constant clock rate.

Abstract: At least one frame of image information of each recording unit composed of a plurality of frames is intraframe-coded, and remaining frames of image information are intraframe-coded to output coded image information. The coded image information is divided into first and second groups in the same frame, and decoding information is added to the divided coded image information of the first and second groups. The first group of divided coded image information with the decoding information added in the recording unit is recorded in a first recording area of a recording medium, and the second group of divided coded image information with the decoding information added in the recording unit is recorded in a second recording area of the recording medium.

Abstract: A transmitter which allows to reproduce a high quality and smooth dynamic image on the receiving side even with a transmission medium having a low transmission rate is provided. Background plane data representing a still image of a background image of video and one or more motion plane data representing still images of each of moving objects moving on the background image are separated from input digital video signal. The separated background plane data and each motion plane data are stored individually in memories 23BG and 23A1 through 23An. Change data on the still images stored as the motion plane data is detected based on the input digital video signal and output of the memories 23BG and 23A1 through 23An to compress and code it by a coding means 26. Still image data of the plurality of plane data of the memory means 23BG and 23A1 through 23An and the change information from the coding means 26 are transmitted.

Abstract: A difference signal generated in a prediction encoding process is block-segmented by a block segmenting circuit 2. Thus, the level distribution of the block-segmented difference signal is concentrated to a narrower portion than the level distribution of one entire screen. Reference values DR and MIN of each block of the difference signal are detected. A quantizing step width .DELTA. and shift data .DELTA.S are determined corresponding to such reference values and the number of quantizing bits N. A quantizing circuit 6 quantizes the difference signal with .DELTA.. The difference signal is shifted and quantized so that the level 0 of the difference signal is obtained as 0 on the decoding side. A flag FLG and a that represent the quantized value of the level 0 are transmitted as side information along with the quantized value Q.