Showing papers on "Residual frame published in 1992"

Image signal band compressing system for digital video tape recorder

Abstract: The image signal band compressing method employs a three-dimensional motion compensating technique, an intraframe and an interframe processes which are alternatively executed. The transfer rate of the intraframe to the interframe is set to 4:1 in a unit of fixed length. The intraframe process is defined such that the present frame image data is compressed in a variable length compressing manner by way of two-dimensional discrete coding transform. The interframe process is defined such that motion data is estimated by comparing the present frame and the preceding frame, the present frame is expected on the basis of the motion data and the difference data between the motion compensated image data and the present frame data.

Interframe motion predicting method and picture signal coding/decoding apparatus

Abstract: An interframe motion predicting method for prediction of the motion in a bidirectionally predictive-coded frame from an intra-coded frame and a predictive-coded frame, predicts the motion in another bidirectionally predictive-coded frame from the preceding bidirectionally predictive-coded frame and the predictive-coded frame. A picture signal coding apparatus executes orthogonal transformation of a picture signal, then quantizes the transformed data, and codes the data thus quantized. The apparatus includes a local decoder for the quantized data; first and second memories for storing the decoded picture data of an intra-coded or bidirectionally predictive-coded frame, and a predictive-coded frame respectively; a predictive picture generator for generating a predictive picture of a second bidirectionally predictive-coded frame; and a difference calculator for calculating the difference between the predictive picture and the original picture signal corresponding thereto. A picture signal decoding apparatus includes inverse multiplexer for separating the coded data into interframe predictive error data and vector coded data; a decoder for generating decoded picture data on the basis of such error data; first and second memories for storing the decoded picture data of the intra-coded frame and the predictive-coded frame respectively; a predictive picture generator for generating a predicted picture of a second bidirectionally predictive-coded frame; and a frame switching selector for selectively rearranging the decoded picture data in the order of reproduction.

System and method for frame differencing video compression and decompression with frame rate scalability

Abstract: A system and method of compressing original video data expressed in a plurality of digitally coded frames which enable decompression and playback of resulting compressed video data at one of a plurality of frame rates while maintaining temporal fidelity of the frames displayed. Compression includes selecting a plurality of rate streams for the compressed video data, including a highest rate stream including all of the frames of the original video data and a lowest rate stream including a subset of regularly spaced frames of the original video data. Then the initial frame in the original video data is spatially compressed and the resulting compressed data placed in the compressed video data. The initial frame is also saved as a base frame for all rate streams for subsequent temporal compression of the original video data. As frames are retrieved from the original video data in sequence, temporal compression based on frame differencing techniques between the retrieved frame and the base is carried out, with difference frames being stored to the compressed video data. Each difference frame is placed in the resulting compressed video data for later decompression and reproduction.

Method and apparatus for communicating compressed digital video signals using multiple processors

Abstract: Digital video signals are processed by a plurality of independently operating processors to provide data for transmission in a compressed, motion compensated form. A video image frame area is divided into a set of subframes. The set of subframes is systematically shifted such that the individual subframes progressively cycle across and wrap around the video image frame area. For each successive video frame, video image data bounded by each of the different subframes is independently compressed using motion estimation to reduce data redundancy among the successive frames. The motion estimation is limited for each subframe of a current video frame to areas of a previous video frame that were bounded by the same subframe in the previous frame. In an illustrated embodiment, the set of subframes is shifted once for each successive video frame, and each subframe includes a refresh region whereby the video image frame area is progressively refreshed as the subframes are shifted thereacross. Receiver apparatus for use in decoding the independently processed subframe data is also disclosed.

Data compression method and apparatus in which quantizing bits are allocated to a block in a present frame in response to the block in a past frame

Abstract: A digital input signal is compressed to provide a compressed output signal in a manner which prevents pre-echo, a common defect of data compressors The digital input signal is divided in time into frames, and into at least one block of data in each frame The frames include a past frame preceding a present frame Block floating is applied to the data in the block in each frame Quantizing bits are adaptively allocated to the data in the block in the present frame in response to the block in the past frame Finally, the resulting quantized data is added to the compressed output signal In a first variation, a signal energy or an allowable noise level is determined for the block in each frame A word length is determined for the block in each frame in response to the determined signal energy or allowable noise level of the block The quantizing bits are allocated to the data in the block in the present frame in response to the word length for the block in the past frame In a second variation, a signal energy in the block in each frame is determined, and quantizing bits are adaptively allocated to the data in the block in the present frame in response to an interpolation between the signal energy for the block in the present frame and for the block in the past frame

Coding means for a signal processing system

Abstract: The coded signal is output with a frame sequence that differs from the frame sequence of the input video signal by outputting the frame information coded by in-frame or inter-frame coding before the frame information coded bay interpolation coding based on the successively preceding frames. Frames immediately preceding a scene change are coded by a method other than field interpolation coding, frames immediately after a scene change are coded by in-frame coding, and the coded information for the frame immediately after the scene change is output after the coded information for the frame immediately before the scene change.

Frame/slot synchronization for u.s. digital cellular tdma radio telephone system

Abstract: Frame/slot synchronization is applied to a received Time Division Multiple Access (TDMA) signal and a temporal position of a reference feature is acquired, such as a synchronizing bit stream or preamble, associated with a desired time slot The desired time slot is but one of a plurality of time slots that comprise a frame Verification that the acquired temporal position corresponds to the desired time slot is performed by repetitively estimating a temporal position of the reference feature in a subsequent frame and sampling the subsequent frame at the estimated temporal position to determine if the reference feature is present The temporal position of the reference feature of the desired time slot relative to the frame is maintained over a plurality of received frames

Moving image compressing and recording medium and moving image data encoder and decoder

Abstract: An interlace-system moving image can be prevented from being blurred when a scene is changed. A frame header is provided at the top of data of one frame formed of two fields and a field flag is recorded in the frame header. The field flag is used to identify whether the frame is started with an odd field or with an even field.

System and method for frame-differencing based video compression/decompression with forward and reverse playback capability

Abstract: A process for coding a plurality of compressed video data streams in a time ordered sequence. Each compressed data stream includes coding of frame to frame differences of a video segment, which are represented as a compressed M×N exclusive-OR plane of pixel change values and location displacement control values for an output pointer into a decompressed video frame. By coding frame to frame differences in an exclusive-OR values, the replay process is made bidirectional, allowing for both forward and reverse playback of the video segment.

Motion filter for digital television system

Abstract: A method and apparatus for processing fields of a video signal that are to be combined into a frame, compressed and communicated over a digital communications system. The processing technique increases the spatial correlation between pixels at a cost of slightly reduced resolution in areas of the frame where there is movement. The method employs a motion detector to separate moving and non-moving areas of the frame. A simple combination of lines from a first field and a second field can be used in static areas. In moving areas, a digital filter is applied to the fields to increase correlation in the resulting field. A digital compression technique such as vector quantization is applied to the resulting frame-based signal.

Standards conversion of digital video signals

Abstract: An input digital video signal is converted to an output digital video signal having a different frame rate and a different number of pixel lines per frame. A first series of progressive scan format frames is formed from the input signal. Then a second series of frames is formed from the first series of frames using motion compensated temporal interpolation between successive frames of the first series in producing at least some of the frames of the second series so as to provide the difference in frame rate. Before or after the second series of frames is formed, vertical spatial interpolation is performed so as to provide the difference in the number of pixel lines per frame.

Digital transmission system, transmitter and receiver for use in the transmission system

Abstract: Digital data are transmitted as packets within frames, at an average frame rate equal to the sampling rate divided by the number of samples per frame. When, as a result of subband or other coding, the number of packets required per frame would not be an integer, frames containing the next lower integer are transmitted, followed by frames containing the next higher integer. Preferably a first portion of each frame contains synchronization information, a second portion contains allocation information, and a third contains samples of, and scale factor information for, the transmitted signal.

Method and circuit for adjusting the size of a video frame

Abstract: In accordance with the present invention, the number of bits used to code a frame of video is controlled by controlling the frame size. In a preprocessing stage (40) of a video coding circuit (10), each frame of video is processed by a low pass anti-aliasing filter (43,44) in the horizontal and vertical directions. The cutoff frequencies in the horizontal and vertical directions are determined by a desired frame reduction factor in the corresponding direction. Then to reduce the sampling rate in each dimension, each frame of video is processed horizontally and vertically by a shift varying filter (45,46). When the sampling rate in both the horizontal and vertical directions is reduced by M/N, the number of code bits decreases linearly with M/N.

A generalized frame synchronizer

Abstract: A modification of the class of frame synchronizers which maximize a likelihood function is proposed. If the stage following the frame sync unit is able to distinguish incorrect from correct syncs, then supplying several alternative frame starting positions effectively improves the synchronization performance. The performance of such a scheme is evaluated analytically and using simulations. As an example system, a frame sync unit followed by a decoder is assumed. The improvement achieved can amount to several decibels, and is excellent at high signal-to-noise ratios. The average overhead, required in the subsequent processing stages is evaluated and shown to be small at signal-to-noise ratios of interest. No changes need to be made to the frame structure, and only slight modifications of the receiver, are necessary. >

Film-to-video frame image conversion apparatus and method for selectively identifying video fields and frames

Abstract: A film-to-video frame image convertor includes a 3-2 pulldown frame convertor for converting signals representing input film frame images, having a lower associated film frame image rate, to signals representing output video frame images having a higher associated video frame image rate. The output video frame images consist of genuine and simulated video frame images, which correspond to actual input film frame images and multiple input film frame images, respectively, in accordance with a 3-2 film-to-video frame pulldown. Each genuine video frame image consists of two video field images corresponding to two actual film field images from the same film frame image. Each simulated video frame image consists of two video field images corresponding to two actual film field images from different film frame images, with one of the two video field images being a duplicate of a video field image in an adjacent video frame image. Identification signals are selectively inserted into the vertical blanking interval of some of the output video frame images to identify which ones are simulated video frame images containing duplicate video field images. This allows the duplicate video field images to be identified and selectively deleted when the video frame images, having the higher associated video frame image rate, are to be reconverted to film frame images having the lower associated film frame image rate.

Adapter for transmission lines using HDLC frames

Abstract: An adapter for connecting a first low bit rate transmission link and a second high bit rate transmission link is disclosed. The adapter receives frames transmitted via the first link. The frames are of variable length and include a flag, an address field, a control field, a variable length data field and a frame check sequence. Each frame also includes after the flag a length code indicative of the frame length, which length code does not alter a frame check sequence of the frame. The adapter includes a processor which determines for each frame in response to the length code a specific time at which the adapter begins transmitting the frame out onto the second transmission link. The specific time is chosen for each frame so that the completion of the transmitting of the frame out on the second link substantially coincides with the completion of the receiving of the frame from the first transmission link. The length code of each frame is removed when it is transmitted out over the second transmission link. The inventive adapter is especially useful is certain kinds of ISDN networks. For example, a fractional terminal equipment (F-TE) may generate the frames with the length codes and transmit these frames in a sub-B channel which runs on an ISDN S/T interface bus at a rate of 64/N kbps, where N is an integer greater than two. The adapter forms part of a fractional network terminator (F-NT) which adapts the frames for transmission on a 64 kbps link, for example, to a central office.

Methods and apparatus for generating a picture-in-picture digital television frame by inserting a mean-only frame into a full-size frame

Abstract: A method for generating a picture-in-picture digital television frame comprises the steps of: converting a first analog television signal into a first digital frame comprising a first prescribed number of pixels; deriving a mean-only frame from the first digital frame, the mean-only frame comprising a second prescribed number of pixels; creating an insertion frame on the basis of the mean-only frame; and inserting the insertion frame into a second digital frame, thereby generating a picture-in-picture digital television frame. A Vector Quantization receiver/decoder comprises a mean-only decode section 20, a full decode section 30, and an image inserter 40.

Motion compensated resolution conversion system

Abstract: A process is provided for creating a high resolution copy of a target video frame selected from a sequence of video frames, wherein each video frame comprises two interlaced fields. The process comprises the steps of: selecting a single field of the target video frame for resolution enhancement; defining a reference target frame having pixel values assigned from the selected single field; defining an enlarged target frame having pixel locations corresponding to the high resolution copy; assigning pixel values from the selected single field to pixel locations in the enlarged target frame which correspond to pixel locations in the selected single field; assigning estimated pixel values to unassigned pixel locations in the reference target frame; selecting a field from one of the video frames in the sequence of video frames which was not chosen as the selected single field as a first object field; estimating motion vectors extending from the reference target frame to pixels in the first object field; identifying accurate motion vectors; assigning the value of a respective pixel for each motion vector identified as accurate to an enlarged target frame pixel location corresponding to an origination point of the motion vector unless the enlarged target frame pixel location was previously assigned a pixel value; and printing the enlarged target frame. Further provided is printing apparatus for creating a high resolution copy of lower resolution video information.

Single split frame mode for a fast frame recorder

Abstract: A fast frame recorder records a scene at a fast frame rate and displays it at a slower frame rate to produce a slow motion replay of the scene. The recorder includes a technique for recording a plurality of split frames of the scene during each frame period to effect an increased frame rate and for displaying the split frames of the scene on a video monitor either simultaneously or sequentially.

Method of disregarding changes in data in a location of a data structure based upon changes in data in nearby locations

Abstract: A method for filtering data to be compressed by frame differencing is disclosed. In applications where large amounts of data must be either stored or transmitted, such as, for example, digital image data, various techniques are used to compress the data. One such technique is frame differencing wherein after a reference frame or key is encoded, only the differences between each frame and the immediately preceding frame in the sequence are encoded. The present invention operates as a pre-process or in conjunction with such a technique by determining which of the changed data points can be disregarded without significantly affecting, for example, the stored image, thereby reducing the amount of data which must be stored or transmitted. The determination is made in the present invention by comparing the pattern of changed data points in the vicinity of the data point under consideration with a set of pre-determined patterns.

Coding and decoding method for voice parameters

Abstract: PURPOSE: To efficiently code linear prediction parameters using correlation between frames even when a coding error is generated in a transmission line, the quality deterioration caused by the error only affects the following limited number of frames. CONSTITUTION: Present frame quantized value x(n) is expressed by a weighted sum of past frame output code vectors x(n-1), x(n-2) and x(n-3) and the present frame output code vectors. The present frame output code vector x(n) is determined to make a distortion d minimum where the distortion d is defined between the vector, which is the sum of the past frame output code vector weighted sum and the code vector taken from a code book 4 multiplied by the present frame weight coefficient, and the present frame linear prediction parameters. COPYRIGHT: (C)1994,JPO&Japio

Digital video signal with increased motion blur characteristic

Abstract: An input digital video signal representing a series of input frames is processed to produce an output digital video signal representing a series of output frames with an increased motion blur effect. For each output frame at least one intermediate field or frame is produced by motion compensated temporal interpolation between a pair of the input frames. Each output frame is then produced by combining the intermediate field or frame with at least one further intermediate field or frame and/or with one of the respective input frames so that the output frame has an increased motion blur characteristic compared with that of the input frames. Using motion compensated temporal interpolation, a change in frame rate can also be produced as between the input frames and the output frames.

Prioritization method and device for speech frames coded by a linear predictive coder

Abstract: A priority assignment method and device are set forth for assigning a priority to a selected speech frame coded by a linear predictive coder based on at least two of: an energy of the speech frame, a log spectral distance between a frame and a frame immediately previous, and a pitch predictor coefficient for the selected speech frame. The invention protects against loss of perceptually important and hard-to-reconstruct speech frames.

Error correction method for multicarrier radio transmission system

Abstract: An error correction system for a multicarrier radio transmission system is provided. At the transmission end, a frame alignment bit and error correction bits are added to each of the signals from a serial/parallel converter. Positions of the frame alignment bits in the signals are controlled by a common frame counter. The signals added to frame alignment bits and error correction bits are radio transmitted on several carriers. At the receiving end, frame alignment of each demodulated signal is established based on demodulated signals transmitted on two carriers. Therefore, even if one carrier is deteriorated, frame alignment of data signals on the carrier can be established based on the frame alignment bit in the other data signal on the intact other carrier.

Frame interpolation system for animation picture

Abstract: PURPOSE: To improve the picture quality of a decoded reproduction picture and to realize the effective utilization of an entire code quantity by improving the efficiency of frame interpolation in a high efficiency coding/decoding of the animation picture employing frame interpolation. CONSTITUTION: A motion detection circuit 11 detects motion information 103 between frames of two frame reference pictures 101, 102. An area detection circuit 12 utilizes motion information 103 to divide the reference pictures 101, 102 for each of object areas of different motion and detects respective area border line as edge information sets 104, 105. A motion compensation control circuit 13 utilizes detected information sets 103, 104, 105 to detect a motion vector 106 and interpolation control information 107 for each picture element of the interpolation frame. A motion compensation interpolation circuit 14 controls the motion compensation frame interpolation processing for each pixel based on the detected information sets 106, 107 and synthesizes an interpolated picture 108 from the two frame reference pictures 101, 102. COPYRIGHT: (C)1994,JPO&Japio

Bidirectional motion estimation based on P frame motion vectors and area overlap

Abstract: Some proposed video compression schemes do not send frames in the order they were captured. Such schemes yield bidirectional or B frames: frames that are predicted from past and future frames. When estimating motion vectors for B frames the motion vector field referencing the future to the past frame (the P frame motion vector field) is available. The area overlap (AO) method presented estimates the motion vector fields relating a B frame to past and future frames using the P frame motion vector field. Thus B frame motion vectors need not be sent AO's estimates are scaled versions of P frame motion vectors and therefore have finer resolution. >

Speech encoder using a soft interpolation decision for spectral parameters

Abstract: A speech encoder uses a soft interpolation decision for spectral parameters. For each frame, the encoder first calculates the residual energy for interpolated spectral parameters, and then calculates the residual energy for non-interpolated spectral parameters. The encoder then compares these residual energy calculations. If the encoder determines that the interpolated spectral parameters yields the lowest residual energy, it indicates to a far-end decoder to use the interpolated values for the current frame. Otherwise, it indicates to the far-end decoder to use the non-interpolated values for the current frame. The encoder signals the far-end decoder as to which spectral parameters (interpolated or non-interpolated values) to use by encoding and transmitting a special signalling bit.

Method and apparatus for scalable decompression of a digital motion video signal using variable pixel depths

Abstract: In a method and apparatus for scalably decoding a sequence of encoded digital video frames on a digital processor, an interpolation level is determined in accordance with the processing power of the digital processor. An encoded frame is selected from the sequence for decoding. If the interpolation level is greater than a predetermined threshold, then a scalably decoded frame is formed by interpolating the selected frame in accordance with a first pixel depth level. If the interpolation level is not greater than the predetermined threshold, then a scalably decoded frame is formed by interpolating the selected frame in accordance with a second pixel depth level, the second pixel depth level having fewer bits than the first pixel depth level.

Motion enhanced compressed video system

Abstract: A compressed video system and method enhances the visual perception of motion for frame rates below 24 frames per second by intentionally introducing a motion smearing for the moving parts of displayed images. The system uses a frame or field buffer between the decompressor and A to D converter that averages the combination of the current frame or field digital video signal values and a progression of decreasing values of previous frame or field elements. Better (e.g. less jerky) moving images with reduced noise generation can be achieved with lower bit rates or bandwidth than with prior systems.

Image compression and storage

Abstract: A sequence of image frames is compressed by dividing each frame into smaller blocks. Each block of all but the initial frame is compared with the corresponding block of the immediately previous frame, with only those blocks that are different being stored. A bit map 22 is used to store information about whether or not each block is different the corresponding block in the immediately preceding frame. To reconstruct a frame, this bit map is scanned for successive frames in reverse order, starting from the bits corresponding to the object frame to be reconstructed to determine in which frame each block last changed. The logical storage page of each block of the image data is then obtained by identifying the frame when that block last changed. Any frame can therefore be quickly reconstructed by accessing only those pages actually used to store block data of the frame to be reconstructed.