Abstract: A free space optics communication apparatus is provided which allows flexible setting in accordance with the number or distances of other apparatuses in single-to-multipoint communication. The free space optics communication apparatus has a movable mirror array which has a plurality of mirrors capable of reflecting a light signal from a light source and arranged in a matrix-like form, and a mirror control circuit for controlling the directions of the respective mirrors to form a plurality of mirror groups which reflect the light signal toward the other apparatuses in the movable mirror array. The number of the mirror groups formed in the movable mirror array through the control of the directions of the mirrors by the mirror control circuit is changeable.

Abstract: A free space optics communication apparatus is provided which allows flexible setting in accordance with the number or distances of other apparatuses in single-to-multipoint communication.

Abstract: Where a recording medium recorded on at a slave side apparatus is reproduced, it has been made possible to perform on cite modification processing identical to that conducted at a master side apparatus, by reproducing, at the master side apparatus, the primary information added with parity symbol for error correction from the recording medium on which the primary information is recorded, correcting the symbol error of primary information reproduced at the reproducing means using the reproduced parity symbol, producing the flag which indicates the production of an uncorrectable symbol error in one unit of a block of a specified amount of information and thus outputting the modification information corresponding to the primary information and the flag and forming, at the slave side, the parity symbol for correction of error of primary information output at the master side apparatus and recording the primary information with the parity symbol and modification information, on the same recording medium.

Abstract: An image processing apparatus comprises a receiving device for receiving encoded image data which is encoded by using orthogonal transform in a predetermined block unit, an error detecting device for detecting a transmission error of the encoded image data, a correcting device for correcting the transmission error in the predetermined block unit, and a decoding device for decoding the encoded image data and outputting image data for reproducing an image. The image processing apparatus satisfactorily controls the amount of compressed data and prevents a deterioration of image quality even if any error occurs on a transmission path, thereby reproducing good image quality.

Abstract: An image coding apparatus comprises a divider for dividing an image into a plurality of coding blocks overlapped to each other, and a coder for coding them for each of the coding blocks divided by the divider.

Abstract: A receiving apparatus receives a hierarchically encoded image signal and detects an error in the image signal. Then a filter process is performed on the image signal, the filter process being controlled based on the output of the error detections. More particularly, the image signal has multiplexed therein a first encoded image signal having a lower image quality and a second encoded image signal for obtaining a higher image quality. These are decoded to obtain a first decoded image signal and a second decoded image signal, and the position of an error in an image frame of the image signal is detected.

Abstract: An information processing method an apparatus are described in which several items of information to be transmitted efficiently within a given frequency band to different receivers. The items of information are multiplexed and used to modulate a carrier whose central frequency is set according to the number of items of information that are multiplexed.

Abstract: Where a recording medium recorded on a slave side apparatus is reproduced, it has been made possible to perform on site modification processing identical to that conducted at a master side apparatus, by reproducing, the primary information added with parity symbol for error correction from the recording medium on which the primary information is recorded, correcting the symbol error of primary information reproduced at the reproducing unit using the reproduced parity symbol, producing the flag which indicates the production of an uncorrectable symbol error in one unit of a block of a specified amount of information and thus outputting the modification information corresponding to the primary information and the flag and forming, at the slave side, the parity symbol for correction of error of primary information output at the master side apparatus and recording the primary information with the parity symbol and modification information, on the same recording medium.

Abstract: An error detection and correction device in which a word train including a number of error correction codes each constructed from a plurality of words is input, the error correction code being of the type that two error words can be corrected by each error correction code. Error words are corrected by using the error correction code within the word train. Mode setting information associated with an error rate of the word train is generated, and an error correction means is controlled in a first or a second error correction mode depending on the mode setting. The error correction means corrects one or two error words for each error correction code in the first error correction mode and corrects only one error word for each error correction code in the second error correction mode.

Abstract: A reproducing method and apparatus for reproducing images by reading an image signal from a recording medium, the image signal including a plurality of blocks each including image data and control data to control reproduction of an image in conjunction with other blocks. The reproducing method includes the steps of reading the image signal from the recording medium; setting a mode from among a plurality of modes including a normal reproduction mode, in which the blocks are read in the reading step in a sequence corresponding to a recording sequence of the image signal, and a special reproduction mode, in which the blocks are read in the reading step in a sequence different from a recording sequence of the image signal; rewriting the control data of a block in the read image signal in the special reproduction mode; and reproducing the image data included in a block in accordance with the control data which is rewritten in the rewriting step.

Abstract: An image processing apparatus comprises a receiving device for receiving encoded image data which is encoded by using orthogonal transform in a predetermined block unit, an error detecting device for detecting a transmission error of the encoded image data, a correcting device for correcting the transmission error in the predetermined block unit, and a decoding device for decoding the encoded image data and outputting image data for reproducing an image. The image processing apparatus satisfactorily controls the amount of compressed data and prevents a deterioration of image quality even if any error occurs on a transmission path, thereby reproducing good image quality.

Abstract: In this image coding method and apparatus, an image is divided into a plurality of areas. Information indicative of the image is variable length coded into data of, for instance (138.times.132) symbols. Boundary information corresponding to the area is transmitted after the data for each 128 symbols, after being variable length coded.

Abstract: An image encoding apparatus for encoding input image data using both of an intrapicture encoding mode and a motion compensation interpicture encoding mode has a refresh area setting section for setting a refresh area to allow an intraimage encoding to be forcibly performed in a picture plane so as to overlap between picture planes in a motion compensation range or more, a refresh control section for forcibly setting an encoding mode of the input image data to the intrapicture encoding mode in the refresh area set by the refresh area setting section, and a cancel section for cancelling a refresh when an image portion as a prediction image of an interpicture encoding has been intrapicture encoded even in the refresh area set by the refresh area setting section.

Abstract: Disclosed are an image coding method and apparatus for coding digital image data in a highly efficient manner, and to an image decoding method and apparatus for decoding the data thus coded. Each image signal constituting the image data is partitioned into a plurality of pixel blocks, and coding of each of the image signals is performed in block units. A plurality of items of coded data obtained by such coding are gathered together to form a block (a re-sync block) corresponding to each image signal. A plurality of the re-sync blocks corresponding to the image signals of an image area of the original image data are sequentially combined, boundary-line information is inserted between mutually adjacent re-sync blocks, and an error correction code is attached to form a code for transmission. In the apparatus for receiving this code, the code is decoded into the original image data by partitioning the code into re-sync blocks and performing decoding and interpolation in re-sync block units.

Abstract: An image processing apparatus comprises a receiving device for receiving encoded image data which is encoded by using orthogonal transform in a predetermined block unit, an error detecting device for detecting a transmission error of the encoded image data, a correcting device for correcting the transmission error in the predetermined block unit, and a decoding device for decoding the encoded image data and outputting image data for reproducing an image. The image processing apparatus satisfactorily controls the amount of compressed data and prevents a deterioration of image quality even if any error occurs on a transmission path, thereby reproducing good image quality.

Abstract: There is provided a coding apparatus comprising: a block dividing section for dividing one picture of an input image signal into (n) blocks; (n) coding sections for coding the image data of each of the (n) blocks; and a control section for dividing one picture of the input image signal into (m) blocks so as to exist over the (n) blocks and for controlling an amount of codes which are generated from each of the coding section every (m) blocks.

Abstract: An error detection and correction device in which a word train including a number of error correction codes each constructed from a plurality of words is input, the error correction code being of the type that two error words can be corrected by each error correction code. Error words are corrected by using the error correction code within the word train. Mode setting information associated with an error rate of the word train is generated, and an error correction means is controlled in a first or a second error correction mode depending on the mode setting. The error correction means corrects one or two error words for each error correction code in the first error correction mode and corrects only one error word for each error correction code in the second error correction mode.

Abstract: An image encoding apparatus includes an encoding unit for encoding an input image signal, a first-data-block generation unit for generating first data blocks, each including encoded data and first additional information, a second-data-block generation unit for generating second data blocks by dividing a string of the first data blocks after every predetermined amount of data, and adding second additional information to each first-data-block string, a first addition unit for adding a first error detecting/correcting code to each of the first data blocks, and a second addition unit for adding a second error detecting/correcting code to each of the second data blocks.

Abstract: An error correcting apparatus including a syndrome calculator for calculating syndromes from input data added with an error correction code, a data memory which is connected in parallel with the syndrome calculator for storing the input data, a syndrome memory to store syndromes calculated by the syndrome calculator, and an error correction processor for executing error correction of the data in the data memory by using the syndromes stored in the syndrome memory. The error correction code is provided in both first and second directions when data is two-dimensionally arranged, and the error correction processor obtains values in which the result of an arithmetic operation for error correction in at least one of the first and second directions is added to syndromes in the other direction. An error position within the input data is detected and corrected again on the basis of the values.

Abstract: An image processing apparatus which conceals image data in accordance with motion data includes an input unit for inputting information data including motion data and image data encoded in accordance with the motion data, a detection unit for detecting error codes in the image data, and a concealment unit for concealing the image data by replacing it by image data of an adjacent picture frame extracted using the motion data.