1021 results about "Reference frame" patented technology

Motion estimation is the science of predicting the current frame in a video sequence from the past frame (or frames), by slicing it into rectangular blocks of pixels, and matching these to past such blocks. The displacement in the spatial position of the block in the current frame with respect to the past frame is called the motion vector. This method of temporally decorrelating the video sequence by finding the best matching blocks from past reference frames—motion estimation—makes up about 80% or more of the computation in a video encoder. That is, it is enormously expensive, and methods do so that are efficient are in high demand. Thus the field of motion estimation within video coding is rich in the breadth and diversity of approaches that have been put forward. Yet it is often the simplest methods that are the most effective. So it is in this case. While it is well-known that a full search over all possible positions within a fixed window is an optimal method in terms of performance, it is generally prohibitive in computation. In this patent disclosure, we define an efficient, new method of searching only a very sparse subset of possible displacement positions (or motion vectors) among all possible ones, to see if we can get a good enough match, and terminate early. This set of sparse subset of motion vectors is preselected, using a priori knowledge and extensive testing on video sequences, so that these “predictors” for the motion vector are essentially magic. The art of this method is the preselection of excellent sparse subsets of vectors, the smart thresholds for acceptance or rejection, and even in the order of the testing prior to decision.

A system and method is provided for coordinating display of synchronized spatial information and time-variant information on a visual interface as a visual representation of a multi-dimensional planned process. The system and method comprise a data store configured for storing the time-variant information, such that the data store is further configured for storing the spatial information as a plurality of data elements for representing visual elements for display in the visual representation with respect to a reference surface. Each of the visual elements is operatively coupled to at least one sequenced element of a plurality of sequenced elements. The system and method also include a synchronization module coupled to the data store and is configured for synchronizing a displayed state on the visual interface of the spatial information with a displayed state on the visual interface of the time-variant information. The time-variant information includes timeline data including at least two of the plurality of sequenced elements having overlapping time spans with respect to a common temporal reference frame, and includes a marker for facilitating navigation of the plurality of sequenced elements with respect to the common temporal reference frame. Changes in the displayed state of the time-variant information are reflected in changes to the displayed state of the spatial information.

A system and method for analyzing a plurality of data elements having both temporal and spatial properties, where a first data element and a second data element of the plurality of data elements are linked by at least one association element. The system and method include selecting the first data element from the plurality of data elements and providing at least one search criteria for use in analyzing the properties of the plurality of data elements with respect to at least one property of the first data element. An analysis module is used to apply the at least one search criteria to the properties of the plurality of data elements for identifying the second data element from the plurality of data elements and the corresponding at least one association element. The at least one association element is configured for representing a connection between the first data element and the second data element, such that the connection has a first property common to a property of the first data element and a second property common to a property of the second data element. A visualization module is used to generate a visual representation of the first and second data elements and the association element configured for display on a user interface for subsequent interaction with user events. The visual representation includes a spatial domain including a reference surface for providing a spatial reference frame having at least two spatial dimensions and a temporal domain operatively coupled to the spatial domain for providing a common temporal reference frame for locations of interest in the spatial domain.

The invention relates to a video encoding and decoding method which is used in a video communication system, wherein the predictive encoding type and reference frame type of a video encoding device are controlled according to the network state and a notice message of a video decoding device. When a network is congested, the video encoding device utilizes a reference frame as a long-term reference frame to perform interframe prediction encoding and judges whether the video decoding device receives the corresponding reference frame according to the notice message of the video decoding device, thus the video encoding device and the video decoding device can utilize the same reference frame. The invention also provides the video encoding device and video decoding device which are used in the method in the invention. The video encoding and decoding method, video encoding device and video decoding device provided by the invention are used to encode and decode a video image by determining the long-term reference frame, thus the video encoding device and the video decoding device can utilize the same reference frame, the decoding error phenomenon caused by packet loss can be avoided and the quality of the video image in video communication can be increased.

A method for intraframe image compression of an image is combined with a method for reducing memory requirements for an interframe image compression. The intraframe image compression includes (a) dividing the image into blocks; (b) selecting a block according to a predetermined sequence; and (c) processing each selected block by: (1) identifying a reference block from previously processed blocks in the image according to an activity metric; and (2) using the reference block, compressing the selected block. The selected block may be compressed by compressing a difference between the selected block and the reference block, where the difference may be offset by a predetermined value. The difference is compressed after determining that an activity metric of the difference block. The activity metric depends on elements of a difference block, which is a block in which elements are each a difference between an element of the current image frame and a corresponding element of the reference frame. The activity metric is a function of the sum of (a) the sum over all rows of all differences between two successive consecutive elements of each row of the difference block; and (b) the sum over all columns of all differences between two consecutive elements of each column of the difference block. The reference block is identified by minimizing a cost function based on the activity metric and either a sum of absolute differences function or a sum of square differences function. The cost function may be a weighted sum of the activity metric and either a sum of absolute differences function or a sum of square differences function, or a weighted sum of the activity function and either a sum of absolute differences function or a sum of square differences function.

The invention provides a method of implementing video code stream frame rate adjustable compression, the type of the compression image comprises I frame, non-I frame, P frame, non-P frame and B frame, in the process of decoding, time domain level of each frame image of I frame or P frame is varied periodically as the size of unit group; in the process of coding, the time domain level of current frame image is determined according to the current frame image coding sequence firstly, and then the reference frame image of current frame image is obtained according to reference frame selection strategy, the current frame image is encoded, the reference frame caching is updated according the reference frame updating strategy after accomplishing coding; in decoding, the time domain level of current frame image is determined according to the current frame image decoding sequence, and then the reference frame image of current frame image is obtained according to reference frame selection strategy, the current frame image is decoded, the reference frame caching is updated according the reference frame updating strategy after accomplishing decoding. The compressed code stream has the function of adjustable frame rate, which is capable of adapting transmission of different networks and display of different terminal device.

When transmission of on-demand video data interrupts transmission of broadcast video data from a distribution server 17 to a user terminal 18, the distribution server 17 transmits substitute I frame data to the terminal 18 after on-demand video data transmission in complete and before resuming broadcast video data transmission. The user terminal 18 decodes and displays the substitute I frame data, and then uses the decoded substitute I frame data as a reference frame to decode and display the first several frames of broadcast video data received directly after resumption of transmission.

The invention provides a motion prediction method. First, a plurality of motion vector predictors is obtained to be included in a candidate set for motion prediction of a current unit of a current frame. Whether the current frame is a non-reference frame which is not referred to by other frames for motion prediction is then determined. When the current frame is not the non-reference frame, any motion vector predictor corresponding to a previously coded frame is removed from the candidate set, and a motion vector of the current unit is predicted according to the motion vector predictors of the candidate set.

A video encoding method comprises storing a plurality of encoded frames (rf0, rf1, rf2) of a video in a memory, generating a to-be-encoded frame (current) which is divided in a plurality of regions (A to E) including at least one encoded region (A to D) and at least one to-be-encoded region (E), generating a predictive vector (MV) of the to-be-encoded region of the to-be-encoded frame using a plurality of motion vectors (RCMV) as a plurality of reference vectors, the motion vectors being generated with respect to at least one reference frame selected from the encoded frames for a motion compensative prediction when encoding an original region of the encoded region around the to-be-encoded region of the to-be-encoded frame, and encoding the to-be-encoded frame to generate encoded video data.

In the video encoding and decoding of digital video sequence having a prediction operation and an update operation, the update operation includes interpolation to generate energy distributed interpolation. Prediction is carried out on each block based on motion compensated prediction with respect to a reference frame and a motion vector in order to provide a corresponding block of prediction residues. Updating is carried out on a reference video frame based on motion compensated prediction with respect to the block of prediction residues and a reverse direction of the motion vector. The interpolation filter is determined based on the motion vector and the sample values of sub-pixel are interpolated using the block prediction residues by treating the sample values outside the block of prediction residues to be zero. Interpolation is performed along horizontal direction and vertical direction separately using one dimensional interpolation filter.

A system and method are provided for using global motion predictors (GMPs) in predictive motion estimation for the compression of video. The method comprises: receiving video frames; generating a set of global motion parameters for a current frame of video; in response to the global motion parameters, generating GMPs for image blocks in the current frame; estimating motion between the current frame and a reference frame; subtracting reference blocks in the reference frame from image blocks in the current frame, leaving residual image blocks; and, encoding the residual image blocks in a video stream. Some aspects of the method further comprise: generating local motion predictors (LMPs). Then, estimating motion between the current frame and a reference frame includes estimating motion using the GMPs and the LMPs. The process of estimating motion typically involves using previously encoded information, such as temporarily distant reference frames or other image blocks in the current frame.