43 results about "Quadtree segmentation" patented technology

The invention provides an encoder, decoder, video frame encoding method and bit stream decoding method. The encoder for receiving a video frame and performing encoding processes to generate an encoded bit stream includes: a fidelity enhancement block, for performing a fidelity enhancement technique on the video frame utilizing a quad- tree partition, and generating fidelity enhancement information including a parameter associated with the quad-tree partition structure; and an entropy coding block, coupled to the fidelity enhancement block, for encoding the fidelity enhancement information, and embedding the encoded fidelity enhancement information into the encoded bit stream. The said method and device make the decoder immediately stores the fidelity enhancement information and execute the fidelity enhancement without waiting for decoding all the bit streams through indicating the position of the fidelity enhancement information by an indicating needle.

A method and apparatus for constructing a map for a mobile robot to be able to reduce a data amount and increase an approach speed. The method includes: searching for a plurality of feature data occupying an arbitrary space by scanning a surrounding environment of the mobile robot; performing quadtree segmentation on first feature data of the plurality of feature data to generate a plurality of first node information as a result of the quadtree segmentation; determining a position of second feature data of the plurality of feature data with respect to the first feature data; and performing a neighborhood moving algorithm for generating a plurality of second node information of the second feature data according to the position of second feature data by using the plurality of first node information.

The invention provides an LOD model generation method based on a linear quadtree. The method comprises the following steps: performing linear quadtree segmentation on to-be-drawn terrain, storing data of the to-be-drawn terrain in a two-dimensional array, reading information of each node in the linear quadtree from the two-dimensional array through an index, storing leaf node information of the linear quadtree, organizing terrain nodes, enabling the terrain nodes in the linear quadtree to be stored in a one-dimensional array, establishing a terrain node evaluation mechanism on the basis that a static error and a dynamic error are considered, performing crack elimination on different segmentation levels of the adjacent terrain nodes, and obtaining an LOD model based on the linear quadtree. The method is applied to a terrain simplification aspect in a computer graphics and image field, and the terrain nodes are organized by utilizing a linear quadtree storage model and through combination use of a two-dimensional filling curve; on the basis that error factors are fully considered, the node evaluation mechanism is established, and a terrain crack problem is eliminated; and terrain drawing efficiency can be obviously improved.

The present invention relates to a method and apparatus for encoding / decoding an image, and to a method and apparatus for recording a quantization parameter differential value based on a quadtree segmentation in a largest coding unit (LCU), and adaptively predicting a quantization parameter value based on context information of a neighboring coding unit (CU). The method and apparatus for encoding / decoding a quantization parameter based on a quadtree structure may effectively present block information having a quantization parameter differential value based on segmentation information of a CU, and may perform an adaptive prediction of a quantization parameter value using the context information of the neighboring CU such as a block size, block segmentation, quantization parameter value, and the like.

The invention discloses a remote-sensing image compression method for discrete wavelet transform based on self-adaptation direction prediction and belongs to the technical field of remote-sensing image processing. The method comprises the steps that 1) 15 directions which are formed by close-end integer and fraction pixels and far-end integer pixels are considered in a combined mode, a direction graph is established; 2) remote-sensing images are subjected to two-dimensional discrete wavelet transform based on self-adaptation direction prediction, namely quadtree division based on direction consistency is used for dividing the remote-sensing images to a plurality of image blocks which are not overlapped, a new direction prediction model is used for obtaining the best transformation direction of each image block, lifting wavelet transform is completed in the direction; 3) a transformed image coefficient is subjected to SPIHT coding, direction information is subjected to self-adaptation arithmetic coding, and a final code stream is obtained. According to the method, visual quality and peak signal-to-noise ratio of the remote-sensing images are effectively improved, computing complexity of direction wavelet transform is lowered, and the method can be widely used for efficient coding compression of the aviation and satellite remote-sensing images.

A method for decoding a video according to the present invention may comprise: determining whether to divide a current block with quad tree partitioning, and dividing the current block into four partitions based on a vertical line and a horizontal line when it is determined that the current block is divided with the quad tree partitioning.

The invention discloses an interframe predication quick mode selecting method for high-performance video coding. The method comprises the steps of conducting SKIP mode and Inter2Nx2N mode verification on each coding unit (CU) in video frames, judging whether the SKIP mode is a current optimized mode or not if the error of the rebuilt pixel and the original pixel value of each CU unit does not surpass a threshold, or the error of the rebuilt pixel and the original pixel value is distributed in a preset range or predicted residuals do not surpass preset numerical value, judging the SKIP mode as the optimized mode of the current CU if SKIP mode is the current optimized mode, otherwise, judging whether the the current CU is a smallest coding unit (SCU) or not, conducting four quad tree based segmentation on the current CU if the current CU is not an SCU, and conducting mode verification on sub-units one by one. The method effectively reduces coding complexity of a coding side so as to be adapted to mobile equipment and much video application high in real-time requirement.

The invention provides a terrain multi-scale TIN (Triangulated Irregular Network) online visualization method oriented to the virtual earth. The method comprises the following steps of global multi-scale TIN scale parameter mathematical model construction, terrain multi-scale TIN automatic construction and virtual segmentation under characteristic constraints, the online visualization of a multi-scale TIN topography spherical surface and real-time crack elimination, wherein the step of the terrain multi-scale TIN automatic construction and virtual segmentation under characteristic constraintsis realized as follows; the step of the online visualization of the multi-scale TIN topography spherical surface comprises the step of carrying out calculation to obtain visual terrain blocks of different levels according to point-of-sight information; and the step of the real-time crack elimination comprises the following step of carrying out quick decoding during real-time visualization to finish the edge connection of the adjacent boundary of terrain blocks of different levels. By use of the method, while the structural flexibility of the TIN is kept, the multi-scale irregular modeling andthe quadtree segmentation of a large-scale terrain are realized, meanwhile, the seamless real-time rendering of a mixed scale TIN terrain is supported, the terrain data processing and expression accuracy of the virtual earth can be greatly improved, a seamless fusion ability for irregular GF spatial data is also greatly improved, so that the high-fidelity expression requirement of a geographical environment can be met, and each category of reliable geographical analysis application can be supported.

The invention discloses a thermodynamic diagram generation method and system considering space density difference, and the method comprises the steps: collecting experiment data, and storing the experiment data in a form of a space point group; in combination with a thermodynamic diagram scale, calculating a real distance corresponding to the screen resolution, and taking the real distance as a side length threshold value of quadtree segmentation; counting the number of the spatial point groups, and calculating a point number threshold value; carrying out quadtree segmentation based on point number threshold and side length threshold constraints on the spatial point group, and extracting block side length information reflecting a point group distribution aggregation degree; calculating adaptive bandwidth values point by point according to the corresponding relation between the side length of the quadtree block and the bandwidth parameter of the nearest neighbor kernel density function;and substituting the adaptive bandwidth value into a nearest neighbor kernel density function, calculating a nearest neighbor kernel density function value, and presenting a result in a Heat-map form. According to the method, quadtree segmentation and the nearest neighbor method are combined, the bandwidth values are calculated point by point, and the real distribution characteristics of the spatial point group are expressed more objectively.

The present invention relates to a method and apparatus for encoding / decoding an image, and to a method and apparatus for recording a quantization parameter differential value based on a quadtree segmentation in a largest coding unit (LCU), and adaptively predicting a quantization parameter value based on context information of a neighboring coding unit (CU). The method and apparatus for encoding / decoding a quantization parameter based on a quadtree structure may effectively present block information having a quantization parameter differential value based on segmentation information of a CU, and may perform an adaptive prediction of a quantization parameter value using the context information of the neighboring CU such as a block size, block segmentation, quantization parameter value, and the like.

The invention discloses an interframe predication quick mode selecting method for high-performance video coding. The method comprises the steps of conducting SKIP mode and Inter2Nx2N mode verification on each coding unit (CU) in video frames, judging whether the SKIP mode is a current optimized mode or not if the error of the rebuilt pixel and the original pixel value of each CU unit does not surpass a threshold, or the error of the rebuilt pixel and the original pixel value is distributed in a preset range or predicted residuals do not surpass preset numerical value, judging the SKIP mode as the optimized mode of the current CU if SKIP mode is the current optimized mode, otherwise, judging whether the the current CU is a smallest coding unit (SCU) or not, conducting four quad tree based segmentation on the current CU if the current CU is not an SCU, and conducting mode verification on sub-units one by one. The method effectively reduces coding complexity of a coding side so as to be adapted to mobile equipment and much video application high in real-time requirement.

The invention discloses a remote-sensing image compression method for discrete wavelet transform based on self-adaptation direction prediction and belongs to the technical field of remote-sensing image processing. The method comprises the steps that 1) 15 directions which are formed by close-end integer and fraction pixels and far-end integer pixels are considered in a combined mode, a direction graph is established; 2) remote-sensing images are subjected to two-dimensional discrete wavelet transform based on self-adaptation direction prediction, namely quadtree division based on direction consistency is used for dividing the remote-sensing images to a plurality of image blocks which are not overlapped, a new direction prediction model is used for obtaining the best transformation direction of each image block, lifting wavelet transform is completed in the direction; 3) a transformed image coefficient is subjected to SPIHT coding, direction information is subjected to self-adaptation arithmetic coding, and a final code stream is obtained. According to the method, visual quality and peak signal-to-noise ratio of the remote-sensing images are effectively improved, computing complexity of direction wavelet transform is lowered, and the method can be widely used for efficient coding compression of the aviation and satellite remote-sensing images.