Showing papers on "Residual frame published in 1993"

Method and apparatus for visual search control of digital video files

Abstract: A visual search control of digital video files capable of realizing a high quality image even in the fast forward and fast reverse modes, while facilitating a quick mode switching among the normal playback mode and the fast forward and fast reverse modes. Each digital video file contains: normal playback data for a normal playback mode; fast forward and fast reverse data for fast forward and fast reverse modes; and a frame management information containing an entry for each frame in the normal playback data and the fast forward and fast reverse data, where each entry registers a frame number of each frame, and a switching target frame number indicating a frame number of a next frame to be read out next when a mode switching occurs; such that when a mode switching request is received along with a currently displayed frame number from a user terminal, an entry in the frame management information which registers the frame number identical to the received currently displayed frame number is looked up to obtain the switching target frame number registered therein and the requested mode switching is made by making an access to the next frame indicated by the obtained switching target frame number, reading out digital video data starting from the next frame, and transferring the read out digital video data to the user terminal.

Method and apparatus for the simultaneous display of one or more selected images

Abstract: A system for displaying selected images on a video display device is provided. One or more sources of image frames are included which sources may be digital or analog and which sources may present pixel data in different selected formats. A frame memory is provided which is adapted to store a plurality of memory frames each of which may store one or more image frames to be displayed. Image frames are selectively stored in the memory frames of the frame memory in the format in which they are received. The images may be stored in full size or may be compressed for windowing display and selected information concerning image frames may be utilized to control the mapping of values stored for the pixels of the image frames. A display frame may be formed of two or more compressed image frames with each image frame being read out from a selected memory frame which memory frame may be independent of or the same as the memory frame for other read out images. Certain images may contain two or more different types of information which may be selectively processed when read out from a frame memory to cause the content of such multiple information images to be displayed as multiple separate images containing the content of the image frame in various permutations and combinations. Color mapping using the same or different criteria may also be provided, with the color mapping being independent for each of the image frames being simultaneously displayed.

Discontinuous CDMA reception

Abstract: A cellular radio telephone system employs discontinuous transmission and reception of speech signals to conserve receiver processing resources. A frame structure is imposed on digitized speech data to divide the data into units of fixed transmission time. When no active speech is present for the entire duration of a frame, transmission of that frame of data is inhibited. At the receiver, decoding of received bits is performed to determine correlation with a defined set of code words. If no correlation is found after the first few received bits of a frame, due to the absence of active speech data, decoding is discontinued for the remainder of the frame's duration. This approach frees up the receiver's resources for other tasks, such as decoding of other received signals. Frames of data from different sources are transmitted with a defined time alignment to enable the receiver to remain synchronized in the absence of transmitted data. The frames associated with different sources are staggered relative to one another, to distribute processing loads at the receiver.

Apparatus and method for providing multiple data streams from stored data using dual memory buffers

Abstract: An apparatus and method are disclosed for processing successive frames of data to provide a plurality of data streams containing the data in different orders. In an illustrated embodiment, two different data streams are output for incoming frames of video data. Pixels are grouped from an incoming current video frame to provide successive pairs thereof for storage in a first memory bank at a first clock rate φ. Stored pixel pairs are read from a second memory bank containing a previous video frame at a second clock rate 2φ while the pairs of pixels from the current video frame are being stored in the first memory bank at rate φ. This provides two pairs of pixels from the previous video frame for each one pair of pixels stored from a current video frame. The pixel pairs from the previous video frame output from the second memory bank are combined into two data streams, each providing the pixels in a different order. The memory banks are alternated to process successive frames.

Suspending, resuming, and interleaving frame-groups

Abstract: A system and method for asynchronously transmitting data blocks, in parallel, across multiple fibers in a serial manner. Frame groups are provided as a mechanism to transmit associated data serially on each fiber and tie the data being transmitted together. The frame groups can be prematurely ended on any 256 byte block boundary for several purposes, and all the frames of a given group must contain the same number of information field data words. Allowing frame groups to be ended on arbitrary block boundaries allows their transmission to start before all of the information field for the frame group has been received from a shared main processor storage. This capability of ending frame groups also allows high priority frame groups to interrupt the transmission of a relatively long data frame. Finally, the capability to end the frame group protects the information field of a stalled frame group since the CRC is sent and the idle sequence is resumed. Using multiple, independently clocked transmitters improves the fault tolerance of the link but also makes it difficult to end all frame of the frame group on the same block boundary. This problem is also solved by keeping track of the data sent to the multiple transmit buffers.

System and method for filtering video signals

Abstract: Motion video is represented by digital signals. The digital signals can be compressed by coding to reduce bitspace. Noise in the signal, however, reduces the efficiency of coding. The present invention is a system and method for reducing noise in video signals by filtering. The signal for the current frame is weightedly averaged with signals for a future and prior frame. The future and prior frames are given less weight as they differ more from the current frame. When motion compensation information is available, the motion compensated future and prior frames can be used for averaging, further improving filtering.

Iterative predictor-based detection of image frame locations

Abstract: Locations of respective image frames contained on an image recording, such as a continuous color photographic film strip scanned by digitizing opto-electronic scanner are identified by storing scanline data produced by the scanner in a digital database, and processing the stored scanline data in accordance with set of image frame identification operators, which iteratively identify locations of nominally valid frames, beginning with the identification of all well formed frames. Each well formed frame has prescribed image frame attributes including at least a spatial region of image modulance bounded by leading and trailing edges adjacent to Dmin interframe gaps. The iterative identification procedure includes `chopping` less than well formed frames, sorting frame regions based upon geometry considerations and identifying and adjusting the size of oversized and undersize frames. To reduce computational complexity a set of image frame-based `predictors` and an associated set of thresholds are used in the iterative search and sort process.

Decoder for a compressed digital video signal using a common memory for decoding and 2/3 pull-down conversion

Abstract: An apparatus for expanding a compressed digital video signal representing a motion picture to provide a digital video output signal. The compressed digital video signal comprises plural interlaced frames with a frame rate of 24 Hz. The digital video output signal comprises plural pictures with a picture rate of at least 49 Hz. The apparatus includes a frame memory comprising no more than four pages, each page storing one frame. The apparatus also includes an expander for expanding the compressed digital video signal to derive a reconstructed interlaced frame from each frame of the compressed digital video signal. Finally, the apparatus includes a controller that controls writing of each reconstructed interlaced frame into one page of the frame memory. The controller also controls reading out of the reconstructed interlaced frames stored in the pages of the frame memory to provide the pictures of the digital video output signal. Reading out is controlled to effect 2-3 pull down conversion of the reconstructed interlaced frames stored in the frame memory with a frame rate of 24 Hz to provide the pictures of the digital video output signal with a picture rate of at least 49 Hz.

Tracking moving objects

Abstract: A method of tracking an object in a sequence of picture frames comprises inputting motion vectors (100) and segmenting the picture into areas of uniform motion (101). For the initial frame (1027) the object is located (103) either automatically or manually and its centroid and motion vector are calculated (104). For each subsequent frame (105) motion vectors (100) are input and the frame is segmented into areas of uniform motion (101). The forward motion vector of the object is calculated (120) and used to project the centroid of the object from the previous frame onto the present frame (106). The object is then grown round the projected centroid (107) by allocating areas similar to areas of the object in the previous frame and which together produce a centroid close to the projected centroid to a set of areas which define the object. A rectangle may then be drawn around the object (109) which may be used in a coding arrangement to define areas of different resolution. Backward motion vectors of the areas within the set are then calculated (110) and used to determine the similarity of areas in the next frame. Apparatus for performing the method is disclosed particularly in relation to tracking a head for videophone communications.

Digital video editor having lost video frame protection

Abstract: A digital video editing apparatus in which the frame number information that is encoded in non-visible portions of frames in an analog video signal is utilized to ensure that there are no missing frames of corresponding digital video information. The frames of analog video information are digitized and stored in the editing apparatus using a two-pass procedure. In the first pass, as many analog video frames as possible are digitized and stored, and the frame numbers from the frames are utilized to form a list of missing frames. In the second pass, the missing frame list is utilized to reposition the analog video source and to read in the missing frames. If desired, a digital frame trap may be provided such that the contents of a temporary frame memory are frozen until computer processing apparatus has enough time permanently to store the trapped frame. Once a complete set of digital frames has been converted and stored, digital video editing may be undertaken, and the edited digital frames may be outputted in analog form.

Frame relay system capable of handling both voice and data frames

Abstract: Modifications to existing frame relay communication protocols are described which permit both voice and data frames to be handled in an integrated frame relay system. A Voice Frame Identifier bit is defined in the address field of a frame. When an intermediate node detects a voice frame, a CRC operation is performed using only the frame header; that is, voice information is excluded from the computation. The frame is flagged for priority processing in the node. When the intermediate node detects a data frame the CRC operation uses both the header and the data fields.

Image signal encoding apparatus using adaptive frame/field format compression

Abstract: Compression of blocks of digital data is optimized by optimally selecting between frame and field format compression on a block-by-block basis. Specifically, a set of pixel data presented in a field format is compressed to provide a field compressed image signal. The set of pixel data is also presented in a frame format to provide a frame compressed image signal. The field and the frame compressed image signals are quantified; and the compressed image signal having the lesser amount of bits is then selected. The selection effectively improves the quality of the transmitted signal and reduces the structural complexity and manufacturing cost of the image signal encoding apparatus.

Software video compression for teleconferencing

Abstract: In a method and apparatus for producing a signal for transmission to a receiver, a video signal is converted to digital form and the data of sequential frames of the signal are arranged in a plurality of blocks of pixel data that numerically represent visual characteristics of the respective pixels of the frame image. Each block is further organized as a matrix of pixel data. The pixel data of the blocks of a "previous" video frame, and a current video frame, are stored in a memory. A row of each block of the current video signal is compared with the corresponding row of the previous video frame, and a list is made of blocks in which the averages of the pixel data exceed a predetermined threshold. The pixel data of the listed blocks with lossy compression, and is encoded for transmission along with high definition data of a predetermined number of blocks of unchanged data. The data of the "previous" frame stored in memory is updated in memory, to continually store a replica of an image that corresponds to the image that should be currently stored in the receiving station.

Video motion vector detection including rotation and/or zoom vector generation

Abstract: Motion vectors from one video frame to another are detected by segmenting a present frame of video data into plural blocks and then comparing a block in the present frame to a corresponding block in a preceding frame to detect rotational and zoom movement of the present block relative to the preceding block, in addition to rectilinear movement.

Apparatus for converting a digital video signal which corresponds to a first scan line format into a digital video signal which corresponds to a different scan

Abstract: Apparatus for converting a digital video signal between two different formats, such as interlaced field and non-interlaced progressive frame, and which avoids filtering and sub-sampling of portions of the video data which are the same in either format. For conversion from interlaced field to progressive frame, only alternate fields of the signal are subjected to digital filtering. The filtered fields are then combined with the non-filtered fields, which are subjected only to an equivalent delay, to derive averaged frames which constitute a progressive frame video signal. For the reverse conversion, alternate scan lines of each frame are sub-sampled and averaged to derive a field which is then interlaced with a field formed by the remaining scan lines of such frame, thereby deriving an interlaced field video signal.

Method and apparatus for decoding moving images encoded by inter-frame prediction and displaying it

Abstract: A method and apparatus for displaying images is presented in which intra-frame encoding is performed on image data at N frame intervals, where the thinned-out frames are encoded by prediction from the preceding frame codes. The frame being decoded is identified when an instruction for temporarily stopping a moving image and displaying it as a still image is given by an operation panel. If the frame being decoded is not an interpolative frame, the decoded image data is displayed when the decoding operation is complete. If, on the other hand, the frame being decoded is an interpolative frame, the intra-frame encoded frame nearest to the frame being decoded, or a predictive frame, is displayed.

Spatial bandwidth testing for digital data-compressed video system

Abstract: Spatial bandwidth testing for digital data-compressed video systems is performed using a complex, or high entropy, test signal. A portion of the test signal is acquired as a control frame. This control frame is divided into a plurality of blocks. Each block is processed by a two-dimensional Discrete Fourier Transform (DFT). The test signal is input to a digital data-compressed video system (10) and a corresponding portion of the output of the video system, a test frame, is acquired (20) and processed (22) in the same manner as the control frame. The resulting coefficient arrays from the control and test frames are compared (28) to each other to obtain an output array of ratios for each block. The ratio of those coefficients corresponding to the predominant frequency of each block of the control frame are displayed (30) as a three-dimensional gain plot. The ratio of those coefficients corresponding to low frequencies of each block of the control frame are displayed as a three-dimensional noise plot. The resulting plots provide an objective, visual indication of the characteristics of the digital data-compressed video system.

Speech decoder for decoding a speech signal using a bad frame masking unit for voiced frame and a bad frame masking unit for unvoiced frame

Abstract: A receiving unit receives input speech data on a frame-by-frame basis. An error detection unit checks whether errors exist in each frame, and outputs a signal indicative thereof to a first switch circuit. The first switch circuit outputs the input speech data to a second switch circuit if an error is detected, while it outputs the input speech data to a speech decoder unit if no error is detected. A data memory stores the input speech data after delaying the data by one frame, and outputs the delayed data to a bad frame masking unit for voiced frame, and a bad frame masking unit for unvoiced frame. The speech decoder unit decodes the input speech data by using spectral parameter data, delay of an adaptive codebook, an index of an excitation codebook, gains of the adaptive and excitation codebooks, and the amplitude of the input speech signal. The speech decoder unit outputs a decoding result to a voiced/unvoiced frame judging unit, as well as to an output terminal. The voiced/unvoiced frame judging unit determines whether a current frame is a voiced frame or an unvoiced frame, and outputs the result of the check to a second switch circuit. The second switch circuit outputs the input data to the bad frame masking unit for voiced frame if it is determined that the current frame is a voiced frame, and it outputs the input data to the bad frame masking unit for unvoiced frame if it is determined that the current frame is an unvoiced frame.

Improving frame synchronization when using convolutional codes

Abstract: Presents a method of improving the performance of a frame synchronizer when the data frames are convolutionally encoded and terminated. Termination of the data helps to ensure correct decoding and reduces the effective rate of the code, especially for short data sequences. The synchronizer makes use of the symbols transmitted for termination in order to increase the probability of correct frame synchronization. The author derives an optimum decision rule and several suboptimal algorithms that considerably reduce computation and complexity. Improvement of several dB in frame sync performance was found by simulations. The technique can be applied to "one shot" (e.g. packet) or continuous transmission applications. Furthermore, no changes need to be made to the frame structure, only modifications of the receiver. >

Limited-domain motion estimation/compensation for video encoding/decoding

Abstract: Methods and apparatuses for encoding video images using motion estimation and decoding encoded video images using motion compensation, where the motion estimation and/or the motion compensation is limited to subimages of the video images as defined by boundaries. Although motion compensation may not be used to estimate pels using data from the previous image frame that lies across the subimage boundaries, motion compensation may be used to estimate a portion of a block of the image frame being decoded using a region from the previous image frame that abuts a subimage boundary and is smaller than the block. The rest of the block may be estimated either by retaining the corresponding pels from the previous image frame or by replicating the pels from the previous image frame that lie along the subimage boundary.

Dual buffer video display system for the display of asynchronous irregular frame rate video data

Abstract: A video signal is received from an asynchronous link (15) at an irregular frame rate for display on a computer monitor 9 at a regular frame rate. Frames are transferred to the monitor via first and second buffers (23, 25). A control process (27) manages the transfer of frames between the first and second buffers and is responsible for deciding if, when and how many frames to transfer, in order to minimise the delay between the incoming image and the displayed image.

Image tracking system and technique

Abstract: An image motion tracking system (10) for use with an image detector (12, 14) having an array of elements in the x and y directions. First, frequency domain representations of an image are created to provide a reference frame of image data and an input frame of image data. A processor (30) is included for detecting a change in phase of the detector (12, 14) with respect to first and second samples of the reference frame relative to corresponding first and second samples of the input frame to discern a displacement of at least a portion of the input frame relative to at least a portion of the reference frame. Finally, the output signal is corrected to compensate for the displacement of the input frame relative to the reference frame.

Simple compositing system which processes one frame of each sequence of frames in turn and combines them in parallel to create the final composite sequence

Abstract: A simple compositing system for combining sequences of images, including graphics and video images, records the sequences onto a disk recorder. A frame from each sequence in turn is processed by a digital picture manipulator channel and stored in a respective frame store. Once one frame from each sequence is processed and stored, the frames from the frame stores are combined in a video combiner to form a composite frame, which is read back into the disk recorder. All of the frames of the sequences are combined in this manner to form composite frames, the totality of composite frames producing a final composite image sequence stored in the disk recorder. The final composite image sequence is then transferred to an output device in real time.

Transmitter and system for discontinuous CDMA transmission

Abstract: of EP0565504A cellular radio telephone system employs discontinuous transmission and reception of speech signals to conserve receiver processing resources. A frame structure is imposed on digitized speech data to divide the data into units of fixed transmission time. When no active speech is present for the entire duration of a frame, transmission of that frame of data is inhibited. At the receiver, decoding of received bits is performed to determine correlation with a defined set of code words. If no correlation is found after the first few received bits of a frame, due to the absence of active speech data, decoding is discontinued for the remainder of the frame's duration. This approach frees up the receiver's resources for other tasks, such as decoding of other received signals. Frames of data from different sources are transmitted with a defined time alignment to enable the receiver to remain synchronized in the absence of transmitted data. The frames associated with different sources are staggered relative to one another, to distribute processing loads at the receiver.

Audio and video signal transmission with error correction - protects data groups with bit quantity fluctuating between frames by sorting data bits w.r.t. their importance and distributing bit groups homogeneously within frame

Abstract: The transmission method distributes data in a frame after re-sorting and spreading of sections having different importance groups (I-IV) and subgroups (a-c) within the basic quantity of bits. The necessary protection against errors in a group and corresp. subgroups is distributed homogeneously over all of the available quantity of bits of the frame. Sections which have approximately equal liability to error are juxtaposed, irrespective of the original group to which they belonged. USE/ADVANTAGE - Esp. in digital audio broadcasting. Improved automatic error protection.

Video coding by segmenting motion vectors and frame differences

Abstract: A segmentation-based video coding technique is presented. A change detector is used to find the regions of interest, i.e., moving areas, and then the moving areas are segmented based on the motion vector information. For the regions where the prediction error, defined by the difference between the original image and the motion-compensated image reconstructed by the motion vector, is large, the frame difference signal is used to supplement the segmentation results. Depending on the region characteristics, each region is represented by the motion vector and the frame difference signal. After postprocessing, the region information and the region boundaries are transmitted. Computer simulation with video sequences shows that the proposed algorithm reduces the trailing effect and gives better performance than the conventional method.

Subrate multi-media data transmission system

Abstract: A .[.substrate.]. .Iadd.sub-rate .Iaddend.multimedia data transmission control system in which transmission frame bits set in a unit of a transmission frame having a repeating cycle of 8 KHz according to the present invention enables it to effect a realtime multiplexed bit allocation in the 8 kbps unit in a variable fashion such that an automatic matching of a transmission frame is achieved at an initiation of a transmission and error check bits of the error correction code are contained in a transmission frame with a satisfactory matching. In addition, the multiframe configuration according to the present invention enables it to handle in an integrated fashion the synchronizations of the voice data frame, the error correction frame, and the video data packet, which as a result minimizes the size of the buffer memories disposed to send and/or to receive motion video and which enables the transmission speed smoothing operation to be accomplished in a simple configuration through an easy control.

Methods of and apparatus for coding television signals having varying frame rates

Abstract: Apparatus for coding a television signal in common image format in which the video frame rate may have any one of a plurality of predetermined different values and the number of pixels or the spatial resolution per video frame of which is the same for all frame rates, comprises a video encoder for coding the video information of each video frame into a format suitable for recording in oblique tracks on a magnetic tape, and an audio encoder for coding the audio information associated with each video frame into blocks for recording with the video information, each audio block comprising digital audio data and a pointer indicating that portion of the block containing the audio data, and preferably also the sample rate of the audio data.

Apparatus with frame check capability for reproducing images by combining outputs of concurrently operating disk players storing portions of the images

Abstract: An image reproduction apparatus with a plurality of disk players which concurrently perform play operation so as to produce a plurality of division video format signal concurrently. The video format signal are combined into a signal/final video format signal. The respective frame numbers extracted from the respective division video format signals are compared with the corresponding designated frame numbers. When the extracted frame number and the designated frame number do not coincide to each other, the corresponding division video format signal is ignored in the synthesis operation for producing the final video format signal.

Decoding system for compact high definition television receivers

Abstract: A simplified decoding system for providing a reduced image frame to a high definition television receiver with a small size screen through the use of d.c. transform coefficients. The decoding system selectively decodes and inverse quantizes d.c. transform coefficients to produce a set of difference data, each of which represents an average of pixel differences between a block of two-dimensional pixels of a current frame and a corresponding block of its preceding frame. Each of two-dimensional motion vectors is also decoded and modified to derive a pixel data from the previous reduced image frame. The derived pixel data and the average pixel difference value are successively combined so as to generate the reduced frame.