Patent application number | Description | Published |
20140040215 | METHOD FOR ENCODING A MESH MODEL, ENCODED MESH MODEL AND METHOD FOR DECODING A MESH MODEL - Many 3D mesh models have a large number of small connected components that are repeated in various positions, scales and orientations. The respective positions are defined by the position of at least one reference point per component. For an enhanced encoding of the positions of the respective reference points, a given space is divided into segments and the number of points lying in each particular segment is determined. When a cell with at least n points is subdivided into child cells, an indication is added indicating if all points of a parent are in only one child cell. If so, the index of the only non-empty child node is encoded, while otherwise the number of points in one of the two child cells is decremented and encoded. The invention avoids non-effective subdivisions of a cell, and therefore improves the compression efficiency. | 02-06-2014 |
20140146043 | METHOD AND DEVICE FOR ENCODING AN ORIENTATION VECTOR OF A CONNECTED COMPONENT, CORRESPONDING DECODING METHOD AND DEVICE AND STORAGE MEDIUM CARRYING SUCH ENCODED DATA - The invention is made in the field of encoding and decoding at least one orientation vector of a connected component. When quantizing vector components for encoding, an acceptable quantization deviation of encoded vector components sometimes leads to unacceptable deviations of calculated vector components. Therefore, a method is proposed which comprises quantizing and de-quantizing a first and a second component of the vector, and encoding the quantized first and second component and a bit signalling the sign of a third component of said vector, using the pre-determined length and the de-quantized first and second component for determining whether a calculated absolute of an approximation of the third component of said vector is smaller than a first threshold, and, if the calculated absolute is smaller than the first threshold, determining, quantizing and encoding a residual between the calculated absolute of the third component and the absolute of the third component. | 05-29-2014 |
20140160241 | SYSTEM AND METHOD FOR ENCODING AND DECODING A BITSTREAM FOR A 3D MODEL HAVING REPETITIVE STRUCTURE - Typically, 3D meshes are represented by three types of data: connectivity data, geometry data and property data. An encoded 3D mesh model can be represented, transmitted and/or stored as a bitstream. While the bitstream embeds all the transformation data, it is efficient and may address several applications, where sometimes either bitstream size or decoding efficiency or error resilience matters the most. Therefore, two mode options are disclosed for how to put the transformation data of one instance, i.e. its position, orientation and scaling factor, in the bitstream. In the first mode, the position, orientation and possible scaling factor of one instance are packed together in the bitstream. In the second mode, transformation data types, for example, the positions, orientations or possible scaling factors of all instances are packed together according to the data type in the bitstream. | 06-12-2014 |
20140285487 | Method and Apparatus for Generating a Bitstream of Repetitive Structure Discovery Based 3D Model Compression - A method and apparatus for generating a bitstream representative of a 3D model, and a method and an apparatus for processing the same. A 3D model is modeled by using a using a ‘pattern-instance’ representation, wherein a pattern is a representative geometry of a repetitive structure, and the connected components belonging to the repetitive structure is call an instance of the corresponding pattern. After discovery of the repetitive structures and their transformations and properties, the present embodiments provide for generating a bitstream in either a first format or a second format. In the first format, the pattern ID and its associated transformation and property information are grouped together in the bitstream, and in the second format the pattern ID, transformation property and property information are grouped together according to information type. | 09-25-2014 |
20140334717 | METHOD AND APPARATUS FOR COMPRESSING TEXTURE INFORMATION OF THREE-DIMENSIONAL (3D) MODELS - A 3D model can be modeled using “pattern-instance?representation. To describe the vertices and triangles, properties of the instance, for example, texture, color, and normal, are adjusted to correspond to the order in the pattern. The texture of an instance is encoded depending on its similarity with the texture of a corresponding pattern. When instance texture is identical or almost identical to the pattern texture, the instance texture is not encoded and the pattern texture will be used to reconstruct the instance texture. When the instance texture is similar to the pattern texture, the instance texture is predictively encoded from the pattern texture, that is, the difference between the instance texture and pattern texture is encoded, and the instance texture is determined as a combination of the pattern texture and the difference. | 11-13-2014 |
20150055882 | VEXTEX CORRECTION METHOD AND APPARATUS FOR ROTATED THREE-DIMENSIONAL (3D) COMPONENTS - A 3D model can be modeled using pattern-instance representation, wherein an instance component may be represented as transformation (for example, rotation, translation, and scaling) of a pattern. Quantization errors may be introduced when encoding rotation information, causing different vertex coordinate errors at different vertices of an instance. To efficiently compensate the vertex coordinate errors, an upper bound can be estimated for the vertex coordinate error of a vertex. Based on the upper bound, the codec decides whether the vertex coordinate error of the vertex needs to be compensated, and decides a quantization parameter for compensating the vertex coordinate error if compensation is needed. The upper bound can be estimated at both the encoder and decoder, and thus, no explicit signaling is needed to indicate whether vertex coordinate error compensation is used or to indicate the quantization parameter for the vertex coordinate error. | 02-26-2015 |
20150078674 | COMPONENT SORTING BASED ENCODING FOR 3D MESH COMPRESSION - A method and an apparatus for 3D model compression are described. Correlation among the components of the 3D model are explored and utilized to increase the compression ratio. A principal parameter is selected and examined for determining a sorting dimension. Components are then sorted according to the sorting dimension. The principal parameter values of the sorted components are incrementally encoded. Other parameters are encoded as usual. The corresponding decoder decodes the principal parameter values of the components incrementally and decodes other parameter values as usual. Further an adaptive bit determination algorithm is disclosed to adaptively determine the number of bits assigned to each parameter value based on the value range thereof and the distortion requirements. | 03-19-2015 |
20150084954 | METHOD AND APPARATUS FOR REPETITIVE STRUCTURE DISCOVERY BASED 3D MODEL COMPRESSION - A 3D model can be modeled using “pattern-instance” representation, wherein an instance component may be represented as transformation (for example, rotation, translation, and scaling) of a pattern. To improve compression efficiency, the quantization parameters for the rotation part and translation part for transformation of an instance can be determined based on the quantization parameter used for encoding a corresponding pattern. Specifically, the quantization parameter for the rotation part may depend on the size of the instance, and the quantization parameter for the translation part may depend on the scale of translation. That is, a larger instance may use a finer quantization parameter for the rotation part. The quantization parameters are so determined that quantization errors caused by compressing the patterns, the translation part of transformation, and the rotation part of transformation are at similar levels. | 03-26-2015 |