摘要:
An apparatus and method for implementing object trajectory segmentation for an image sequence. Specifically, block-based motion vectors for a pair of adjacent frames are used to derive optical flow, e.g., affine, motion parameters. The object trajectory segmenter applies the optical flow motion parameters to form a new prediction or method for predicting the positions of all the points on an object over time within an interval. The new prediction is then applied and the result is compared with an error metric. The results from such comparison with the error metric will dictate the proper intervals (temporal boundaries) of the image sequence at which the motion parameters are valid for various key objects.
摘要:
An apparatus and method for implementing object motion segmentation and object trajectory segmentation for an image sequence. Specifically, block-based motion vectors for a pair of adjacent frames are used to derive optical flow, e.g., affine, motion parameters. Such optical flow motion parameters are employed to determine key objects where their motion and trajectory within a sequence of frames are calculated and stored. Such object motion information is used to improve or offer image processing functions such as context-based indexing of the input image sequence by using motion-based information.
摘要:
A method and apparatus for recursively optimizing the rate control of a hierarchical subband coding system that offers spatial, quality and/or complexity scalabilities. The rate control method recursively adjusts the quantizer scale for each layer of a subband tree, i.e., a subband decomposed image.
摘要:
An apparatus and a concomitant method is disclosed for recovering or adjusting quantized coefficients by using a nonlinear method. The method operates by fitting the received signal into one of several predefined classes, and adjusting the signal as appropriate to better fit the best suited class.
摘要:
Post multi-modal coding overcomes the shortcomings of video encoders which fail to meet an expected quality standard while encoding some portions of a video. The deficient encoding is typically due to the type of video content or the encoding technique. A method to improve the quality of the deficient portions, identifies macroblocks that are encoded at a deficient quality. Then, the identified macroblocks are encoded with another suitable encoding technique so that the desired quality is met. The improved macroblocks are then inserted into the original bit-stream, replacing the lower quality sections.
摘要:
Apparatus and method for encoding zerotrees in a wavelet-based coding technique. The method uses a depth-first pattern for traversing the zerotree, i.e., each branch of the tree, from parent to child to grandchild and so on, is fully traversed before a next branch is traversed. The depth-first tree traversal pattern is used to quantize the coefficients of the tree as well as to assign symbols to the quantized coefficients. The method assigns one of three symbols to each node: ZEROTREE ROOT, VALUED ZEROTREE ROOT, and VALUE. By using three symbols and the efficient tree traversal pattern, the method is substantially more efficient at encoding a zerotree than the prior art. Additionally, this concept is applied to the encoding of “vector” zerotrees.
摘要:
An apparatus and a concomitant method is disclosed for encoding wavelet trees in a wavelet-based coding technique using backward predictive coding of wavelet transformed coefficients, which addresses both balanced and unbalanced wavelet trees and increases the overall coding efficiency.
摘要:
The dominant gradient method for finding focused objects determines focused objects within an image or video frame using a dominant gradient method. The method also uses a segmentation map of the image to determine parameters which are used in ranking the objects based on their focus. The ranking of the objects is able to be used to assist in enhancing the image, encoding the image and adjusting the lens while capturing the image.
摘要:
Method and apparatus for intra-prediction in a video encoder are described. An aspect relates to a method of intra-prediction for a group of samples in an image being coded. In some examples, the method includes: defining a target template for the group of samples; comparing the target template with affine transformations of candidate templates within a search area of the image; identifying at least one matching template of the candidate templates as matching the target template; determining a candidate group of samples based on the at least one matching template; and coding the group of samples using the candidate group of samples as a predictor.
摘要:
A generic spatially scalable shape encoding apparatus and method for deriving shape information for chrominance components from luminance component. The present generic spatially-scalable shape encoding applies a series of subband (e.g., wavelet) filters to obtain N-levels of wavelet decomposition for the texture information of both luminance and chrominance components. The application of the corresponding subsampling filters of said subband filters is applied in a manner such that the shape of the chrominance can be derived from the shape of the luminance at the same spatial layer.