Abstract: Technique for coding video images by filtering the original input image into subband images using successive high-pass and low-pass filterings over a tree-shaped filter bank. Each subband image is then submitted to activity detection and coded with a different number of levels depending on the activity detected and on the subband involved.
March 17, 1995
Date of Patent:
May 13, 1997
International Business Machines Corporation
Jean Menez, Michele Rosso, Paolo Scotton
Abstract: An image encoding and transmitting system is an image transmission system for transmitting digital data such as TV telephones. The system for dividing input frame data into a plurality of blocks before transmitting them comprises on its sending side an intra-frame/inter-frame determiner for receiving intra-frame data and inter-frame data and selecting either of them for output, and a difference collator for having the intra-frame/inter-frame determiner compulsorily output intra-frame data at the time of data input for the next frame when one or more data in each block forming inter-frame data are larger than a predetermined threshold. The system also comprises on its receiving side an picture element domain frame data storage for storing received data in the picture element domain, and a motion vector detector for detecting according to the contents in the storage a motion vector using the data in the block surrounding the discarded block in order to guess the data in the discarded block.
Abstract: An apparatus, for use in a motion-compensated video signal encoder, for determining a predicted current frame based on a current frame and a previous frame, includes: a feature point motion vector detector for selecting a number of feature points among edge points in the previous frame and detecting a first set of motion vectors therefor; an edge point motion vector detector for detecting a second set of motion vectors for non-selected edge points; a quasi-point detector for detecting quasi-feature points and a third set of motion vectors, and quasi-edge points and a fourth set of motion vectors; a non-quasi-point motion vector detector for selecting one or more influential quasi-feature points for all non-quasi-points such that straight line drawn between each of the non-quasi-points and each of the corresponding one or more influential quasi-feature points intersects none of the quasi-feature and the quasi-edge points, and detecting a fifth set of motion vectors for the non-quasi-points; an arrangement bloc
Abstract: An apparatus, for use in a motion-compensated video signal encoder, for determining a predicted current frame based on a current and a previous frame, includes: a feature point motion vector(MV) detector for detecting a first set of MVs for feature points and a second set of MVs for edge points in the previous frame; a quasi-point detector for detecting quasi-feature points and a third set of MVs therefor, and quasi-edge points and a fourth set of MVs therefor; a non quasi-point MV detector for determining a quasi-feature point range for each of the quasi-feature points by indexing each of non-quasi-points to its closest quasi-feature point, and detecting a distance between a quasi-feature point and each of the remaining pixels in a quasi-feature point range and setting the distance as a search radius for the remaining pixel, and determining one or more quasi-feature point ranges dispersed within the search radius from each of the remaining pixels, and detecting a fifth set of MVs for the remaining pixels, ea
Abstract: A PC-based system for monitoring and storing representative images from video cameras may be utilized for security or other monitoring applications. Camera inputs from digital or analog sources are individually and independently digitized and displayed at a first set of image sizes, sampling rates, and frame rates, and may be stored in digital form on various recording media at a second set of image sizes, sampling rates, and frame rates, and these two sets of sizes and rates may or may not be identical. Provisions are included for adding detection or alarm systems which will automatically alter image size, sampling rate and/or frame rate of an individual input source, or activate other physical responses. In addition to security system monitoring, further applications of the invention are disclosed for process monitoring in manufacturing environments and also for applications in videoconferencing.
Abstract: An apparatus for reproducing images recorded on successive frames of a film recorded with information, the apparatus includes a film feeder which feeds the film in a first direction and a second direction opposite to the first direction; an information reader which reads the recorded information; a density detector which detects a density of each image; and a controller which controls the film feeder, information reader, and density detector. The information reader is worked when the film is fed in the first direction, the density detector is worked when the film is fed in the second direction. A detected image density is adapted for determining an exposure value at which each image is picked up to reproduce the image.
Abstract: A video system is disclosed in which a single generic MPEG standard encoder (107) is used to simultaneously code and compress plural different resolution video signals from a single input video signal; and in which a single generic MPEG standard decoder (402) is used to simultaneously decode plural coded and compressed video signals of different resolutions and form a single composite video signal. The coder converts each frame of pixel data of the input video signal into plural frames having different resolutions, which are then combined into a common frame (106) for input to the generic MPEG encoder. The MPEG encoder produces a single coded and compressed output bitstream in slices of microblocks of pixel data, which output bitstream is demultiplexed (108) into separate resolution bitstreams using Slice Start Code identifiers associated with each slice and Macroblock Address Increments associated with the first macroblock in each slice, to properly route each slice to the appropriate output.
July 7, 1995
Date of Patent:
April 22, 1997
Lucent Technologies Inc.
Mehmet R. Civanlar, Robert D. Gaglianello
Abstract: Data transfer and timing in an external DRAM memory of an MPEG decoder utilizes a repetitive pattern for synchronous writing and reading of data and data refresh including a sequence header at the beginning of a picture, a macroblock header for each of the macroblocks of a picture, and a plurality of repetitions of block decoding after each macroblock header decode.
Abstract: A sighting direction detecting device including a TV camera which is disposed to face a human being and picks up an image of light invisible to human beings, a first illuminator which is disposed in a coaxial system with the TV camera and illuminates a human's eye-ball portion with light which is invisible to human beings, a second illuminator which is disposed at a different place from the first illuminator and illuminates the human's eye-ball portion with light which is invisible to human beings, a first calculator for calculating an equation of a line passing the pupil center position of the eye-ball, an equation of a line passing the reflected-light position of the first illuminator and an equation of a line passing the reflected-light position of the second illuminator on the basis of the image which is picked up by the camera, a second calculator for calculating the center position of a cornea ball on the basis of the equation of the line passing the reflected-light position of the first illuminator and
Abstract: An image motion compensating address generator is disclosed including a mode selector for selecting a field mode or frame mode according to a video mode signal and a slice position signal, an address selection controller for controlling the generation of addresses according to the video mode signal and a motion coding type signal, a Y-direction read address generator for producing a Y-direction read address in units of processed block, an X-direction read address generator for dividing the processed block into four phases in the X direction and generating an X-direction read address, an X-direction write address generator for delaying the processed-block position signal and a field processed-block clock signal, and generating the X-direction write address of four phases, a Y-direction write address generator for producing a Y-direction write address, and a read & write controller for selectively outputting the X-direction and Y-direction read and write addresses according to a read/write selection toggle sign
Abstract: An improved motion estimating method serves to determine a set of target motion vectors between a current frame and its previous selected frame, wherein N number of frames are skipped between the current frame and the previous selected frame, said N being a positive integer inclusive of 1. This method is implemented through the use of all frames, i.e., the current and the previous selected frames and the N number of skipped frames in order to obtain a series of motion vectors for one of the search points within the previous selected frame. Said series of motion vectors is then summed up to define a target motion vector representing the displacement between said one of the search points and the corresponding best matching point in the current frame. The process is repeated until the set of target motion vectors for all of the search points contained in the previous selected frame are detected.
Abstract: A video decoder including a control unit (CC), a picture memory (P) and a loop filter (F) for blockwise decoding of coded video pictures (q). The blockwise decoding generally leads to artefacts in the display of the decoded video pictures on a monitor (M), which artefacts can be substantially suppressed by filters arranged downstream of the decoder. A similarly substantial suppression of the artefacts with a small extension of the number of components is characterized by means with which the control unit (CC) is enabled, in the decoding intervals,(a) to read predetermined pixel data of a decoded video picture from the picture memory (P) and to apply them to the loop filter (F) for the purpose of filtering,(b) to select the predetermined pixel data in such a way that the filtering operation is performed beyond the block edges of the blocks provided for decoding. The measures described are compatible with a decoder as defined in the H.261 Recommendation.
Abstract: A freezing unit of the present invention includes a color discrepant magnitude detection unit for accumulating the color corrected magnitude for each pixel output from a color discrepancy correction circuit, and detecting it as the color discrepant magnitude for one field. The freezing unit also includes a comparator circuit including a memory for storing the color discrepant magnitudes for sixteen fields, and a comparator for comparing the color discrepant magnitudes for sixteen fields to search a field with the least color discrepant magnitude, and a memory for storing sixteen field images. The freezing unit further includes a reference position selection circuit for selecting the reference position of the image by the freezing signal, and an image selection circuit for selecting the address of an image of a field with the least color discrepant magnitude.
Abstract: A movement detection device includes a first detection unit which detects a high-frequency component of an image signal in units of blocks each consisting of a plurality of pixel data. A second detection unit detects a low-frequency component of the image signal in units of blocks, and a discrimination unit discriminates a movement of the image signal in accordance with outputs from the first and second detection units. Also included is an encoding apparatus having an input unit which inputs image data, and a block forming unit which divides the input image data input into blocks. An orthogonal transform unit orthogonally transforms the image data blocks, and a quantization unit quantizes the orthogonally transformed image data. A detection unit detects the degree of fineness of each image data block, and a control unit performs switching control of a processing method of the orthogonal transform unit in accordance with an output from the detection unit.
Abstract: Methods and apparatus for implementing a reduced cost HDTV/SDTV video decoder are disclosed. The described joint video decoder is capable of decoding HDTV pictures at approximately the resolution of standard definition television pictures and can be used to decode HDTV and/or SDTV pictures. The described video decoder may be used as part of a picture-in-picture decoder circuit for providing picture-in-picture capability without providing multiple full resolution video decoders. The reduction in decoder circuit complexity is achieved through the use of a plurality of data reduction techniques including the use of a preparser, downsampling, and truncating pixel values.
Abstract: A method and apparatus for motion estimation in accordance with the present invention compares image signals of image blocks within a previous frame corresponding to a motion vector detected among error values used for detecting the motion vector of a pixel unit and surrounding image blocks which are generated by moving the reference image block to every direction per one pixel respectively with the image signal of image blocks within a present frame which the motion estimation is performed, and then generates error values according to the comparison results. By vertically comparing the generated error values, a vertical component in the motion vector of a half-pixel unit is detected. By horizontally comparing the generated error values, a horizontal component to the motion vector of a half-pixel unit is detected. Accordingly, the present invention leads to a greater efficiency to reduce the amount of data to be processed for the detection of the motion vector of a half-pixel unit.
Abstract: An encoding unit encodes the received image data in frame units. A code buffer stores the amount of codes per 1 frame. The detection condition setting unit sets a detection condition (a standard value of a code amount difference) specified according to the detection designation data entered externally. A scene determining unit calculates the difference between the amount of codes in the present frame entered from the code buffer and the amount of codes in the previous frame. If the difference is larger than the detection condition (the standard value of the code amount difference), the scene determining unit issues a COS code indicating a scene-changed frame and sets a selection signal in an active state. A switch adds the COS code to the encoded data in the present frame and externally outputs it when the selection signal indicates an active state.
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.
Abstract: Methods and apparatus for reducing the complexity of decoder circuitry and video decoder memory requirements are disclosed. The described video decoders are capable of decoding HDTV pictures at approximately the resolution of standard definition television pictures and can be used to decode HDTV and/or SDTV pictures. The described video decoder may be used as part of a picture-in-picture decoder circuit for providing picture-in-picture capability without providing multiple full resolution video decoders. The reduction in decoder circuit complexity is achieved through the use of a plurality of data reduction techniques including the use of a preparser, downsampling, and truncating pixel values.
Abstract: The present invention provides a method and apparatus for detecting occluded areas in a video frame. A previous displacement vector field, DVF, is motion compensated (402) and used to provide an occlusion test parameter (404) which is compared to an optimal threshold (408) to detect occluded areas. The optimal threshold is calculated based on the previous DVF and a predetermined threshold (406).
July 24, 1995
Date of Patent:
March 18, 1997
Taner Ozcelik, James C. Brailean, Aggelos K. Katsaggelos