Irregular pyramids are made of a stack of successively reduced graphs embedded in the plane. Such pyramids are used within the segmentation framework to encode a hierarchy of partitions. The different graph models used within the irregular pyramid framework encode different types of relationships between regions. This paper compares different graph models used within the irregular pyramid frame...

In this correspondence, a fast approach to motion estimation is presented. The algorithm uses the block sum pyramid to eliminate unnecessary search positions. It first constructs the sum pyramid structure of a block. Successive elimination is then performed hierarchically from the top level to the bottom level of the pyramid. Many search positions can be skipped from being considered as the bes...

Self-regulation by the health professions, while improving, is no longer enough; external drivers for safer health care include governments, funders and consumers. Enforced self-regulation is often more promising than a "command and control" strategy. Research evidence on the responsive regulatory pyramid and its options offers lessons for health care policy makers and managers. Start at the ba...

We consider the transform from sequences to triangular arrays defined in terms of generating functions by f(x) → 1−x 1−xyf (x(1−x) 1−xy ) . We establish a criterion for the transform of a nonnegative sequence to be nonnegative, and we show the transform counts certain classes of lattice paths by number of so-called pyramid ascents and certain classes of partitions into sets of lists (blocks) by...

CNN architectures have terrific recognition performance but rely on spatial pooling which makes it difficult to adapt them to tasks that require dense, pixel-accurate labeling. This paper makes two contributions: (1) We demonstrate that while the apparent spatial resolution of convolutional feature maps is low, the high-dimensional feature representation contains significant sub-pixel localizat...

An important goal of research in computer vision systems is to develop architectures which are general and robust and at the same time transparent and easily transferable from one domain to another. To this extent this paper discusses and demonstrates the versatility of a multi-object tracking framework based on the so called knowledge hierarchy. The systematic description and analysis of a pri...

Segmentation in regions may be achieved using pyra-midal methods that provide hierarchical partitions of the original image. The irregular pyramid is a stack of adjacency graphs of the regions in which the shape of the regions is content based. Using the hierarchical decomposition of an image given by this pyramid, a multiresolution oriented process is proposed. Many segmentations at diierent r...

This paper investigates how structures of pairwise pixel interactions are changing at subsequent levels of Gaussian or Laplacian pyramids representing spatially homogeneous image textures. Structural differences between the parent and child levels of the pyramid are analysed using the modelbased interaction maps (MBIM) describing relative interaction energies in a generic Gibbs random field mod...

Laplacian pyramid based nonlinear diffusion (LPND) method is proposed for speckle noise reduction in medical ultrasound imaging. In this method, speckle is removed by nonlinear diffusion filtering of bandpass ultrasound images in Laplacian pyramid domain. For nonlinear diffusion in each pyramid layer, a Bayesian threshold is automatically determined by a variation of robust median estimator. Th...

We define a global matching framework based on energy pyramid, the Global Matching via Energy Pyramid (GM-EP) algorithm, which estimates the disparity map from a single stereo-pair by solving an energy minimization problem. We efficiently address this minimization by globally optimizing a coarse to fine sequence of sparse Conditional Random Fields (CRF) directly defined on the energy. This glob...