Abstract: A three-dimensional data encoding method includes: extracting, from first three-dimensional data, second three-dimensional data having an amount of a feature greater than or equal to a threshold; and encoding the second three-dimensional data to generate first encoded three-dimensional data. For example, the three-dimensional data encoding method may further include encoding the first three-dimensional data to generate the second encoded three-dimensional data.

Abstract: A calibrator for cameras includes a controlling circuit, a photographing circuit, a calculating circuit, and an instructing circuit. The controlling circuit is configured to control a movable body in a shooting area of the cameras. A marker is provided on the movable body for calibration of the cameras. The photographing circuit is configured to control the cameras to photograph the marker at a first position at a first timing to generate first images. The photographing circuit is configured to control the cameras to photograph the marker at a second position at a second timing to generate second images. The calculating circuit is configured to calculate parameters of the cameras based on the first images and the second images. The instructing circuit is configured to transmit the parameters to the cameras to calibrate the cameras.

Abstract: An image forming apparatus has a heating roller and a pressing roller, a nip being formed therebetween, and a controller configured to perform a heating controlling process of raising the temperature of the heating roller toward a fixing temperature, a rotational controlling process of rotating the heating roller and the pressing roller when a detected temperature of the heating roller is equal to or higher than a first threshold temperature, and a conveyance controlling process of conveying the sheet toward the developing device when the detected temperature is equal to or higher than a second temperature higher than the first temperature and lower than the fixing temperature. The controller is configured to set the first temperature to be lower in a case where a nip width is the second width than in a case where the nip width is the first width.

Abstract: This image generation method is for generating a virtual image by a processor using at least one of images obtained by cameras disposed in different positions and attitudes capturing the same target space in a three-dimensional (3D) space. The virtual image is a two-dimensional (2D) image of the target space viewed from a virtual viewpoint in the 3D space. When generating the virtual image using one or more second images captured by one or more second cameras, at least one of which is different from one or more first cameras that capture one or more first images serving as a basis among the images, a second process which includes at least one of luminance and color adjustments and is different from a first process performed to generate the virtual image using the one or more first images is performed on the one or more second images.

Abstract: A multiple viewpoint image capturing system includes: a plurality of cameras that capture videos in a predetermined space from different positions; a circumstance sensing unit that senses at least one of circumstances of the respective cameras and circumstances of the predetermined space, and outputs the sensed circumstances in a form of capturing circumstance information; and an event detector that detects a predetermined event based on the capturing circumstance information, determines whether to perform camera calibration in a case of detecting the predetermined event, and outputs camera calibration information that indicates the camera calibration to be performed in a case of determining that the camera calibration is to be performed.

Abstract: A free-viewpoint video generating method includes obtaining a multi-viewpoint video including N videos of N viewpoints (N being an integer greater than 1), and generating a free-viewpoint video of a virtual viewpoint based on the multi-viewpoint video such that the free-viewpoint video shows target areas and has a first resolution higher than each of resolutions of the N videos, the virtual viewpoint being different from the N viewpoints. For each target area, the generating includes: referring to a three-dimensional model generated based on the N videos to specify N reference areas which are shown by the N videos and which correspond to the each target area in the free-viewpoint video; and calculating components of pixels to represent the each target area in the free-viewpoint video, based on components of pixels to represent the N reference areas in the N videos.

Abstract: A three-dimensional model distribution method includes: distributing a first model, which is a three-dimensional model of a target space in a target time period, in a first distribution mode; and distributing a second model, which is a three-dimensional model of the target space in the target time period and makes a smaller change per unit time than the first model, in a second distribution mode different from the first distribution mode.

Abstract: A generation method for generating a free viewpoint image includes: receiving place information and a first time information from a display device, the place information indicating a place shown by the free viewpoint image, the first time information indicating a first time period; transmitting, to the display device, a video generated by imaging the place in the first time period; receiving designated-time information indicating a designated time from the display device, the designated time being input to the display device according to the video such that the designated time is provided in the first time period; generating the free viewpoint image to show the place at the designated time from a free viewpoint; and transmitting the free viewpoint image to the display device.

Abstract: A method for analyzing a three-dimensional model of an object which includes: obtaining the three-dimensional model generated based on images of the object, the images being imaged by respective cameras from respective viewpoints, the three-dimensional model including three-dimensional points each of which indicating a position of the object; obtaining a camera parameter of one camera among the respective cameras; generating, based on the camera parameter and the three-dimensional model, a depth image indicating a distance between the one camera and the object; generating a foreground image indicating an area in which the object is present in the one image imaged by the one camera; comparing the depth image and the foreground image to determine whether there is a deficiency of a three-dimensional point in the three-dimensional model; and outputting deficiency information if it is determined that there is the deficiency of the three-dimensional point in the three-dimensional model.

Abstract: A method of generating a three-dimensional model includes: calculating camera parameters of n cameras based on m first images, the m first images being captured from m different viewpoints by the n cameras, n being an integer greater than one, m being an integer greater than n; and generating the three-dimensional model based on n second images and the camera parameters, the n second images being captured from n different viewpoints by the n cameras, respectively.

Abstract: A calibration apparatus calibrates parameters of imaging apparatuses which are disposed at different positions and image a common three-dimensional space. The calibration apparatus includes: an obtaining circuit which obtains videos captured by the imaging apparatuses and each including frames; an extraction circuit which extracts feature points from the frames included in the videos, the feature points including first feature points extracted from first frames included in the videos and second feature points extracted from areas containing an image of a moving object in second frames included in the videos and different from the first frames; a matching circuit which performs matching using the feature points, the matching including matching between the first feature points and matching between the second feature points; and a calibration circuit which calculates parameters of the imaging apparatuses based on first matching results obtained through the matching by the matching circuit.

Abstract: A three-dimensional model processing method includes: generating, from first images shot by respective cameras at a first time, a first three-dimensional model including: first three-dimensional points indicating a subject at the first time; and first camera parameters indicating positions and orientations of the cameras; generating, from second images shot by the respective cameras at a second time, a second three-dimensional model including: second three-dimensional points indicating the subject at the second time; and second camera parameters indicating positions and orientations of the cameras; detecting a stationary camera among the cameras, whose position and orientation has not changed between the first and second times, or stationary three-dimensional points among the three-dimensional points, whose positions have not changed between the first and second times; and matching world coordinate systems of the first and second three-dimensional models, based on the first camera parameters of the stationary

Abstract: A three-dimensional model generating device includes: a converted image generating unit that, for each of input images included in one or more items of video data and having mutually different viewpoints, generates a converted image from the input image that includes fewer pixels than the input image; a camera parameter estimating unit that detects features in the converted images and estimates, for each of the input images, a camera parameter at a capture time of the input image, based on a pair of similar features between two of the converted images; and a three-dimensional model generating unit that generates a three-dimensional model using the input images and the camera parameters.

Abstract: In this steel component, the concentration of C in a surface layer is 0.85 mass % or more to 1.2 mass % or less, which is higher than the concentration of C in a starting material steel, the surface layer has a volume ratio of a retained-austenite structure higher than 0% and lower than 10%, the remainder of the surface layer is a martensitic structure, the area fraction of grain boundary carbides in the surface layer is lower than 2%, a layer inside the surface layer is higher than the surface layer in a volume ratio of a retained-austenite structure, and in the layer inside the surface layer, the remainder is a martensitic structure.

Abstract: A three-dimensional data encoding method includes: generating a bit sequence including N-bit information that is information of a current node included in an N-ary tree structure of three-dimensional points included in three-dimensional data and that indicates whether a three-dimensional point is present in each of child nodes belonging to the current node, where N is an integer greater than or equal to 2; generating (i) position information indicating a head position that is a position at which a predetermined code appears first in the bit sequence when the bit sequence is scanned in a predetermined scan order, and (ii) a remaining bit that is part of the bit sequence after the head position in the predetermined scan order; and encoding the position information and the remaining bit as information of the current node.

Abstract: A three-dimensional data creation method includes: creating first three-dimensional data from information detected by a sensor; receiving encoded three-dimensional data that is obtained by encoding second three-dimensional data; decoding the received encoded three-dimensional data to obtain the second three-dimensional data; and merging the first three-dimensional data with the second three-dimensional data to create third three-dimensional data.

Abstract: A bearing steel part having a predetermined chemical composition, in which the number density of oxide particles having an equivalent circle diameter of 5 ?m or more, and containing CaO, Al2O3 and SiO2, such that the content ratio of Al2O3 with respect to the total mass of CaO, Al2O3, and SiO2 is 50% by mass or more, is 3.0/cm2 or less in an arbitrary cross section of the part, and in which the Vickers hardness at a depth of 50 ?m from a rolling surface is 750 or more, and in which the compressive residual stress at the rolling surface is 900 MPa or more. Also provided is a steel bar for a bearing steel part that is suitable for obtaining the foregoing bearing steel part.

Abstract: Steel according to one embodiment of the present invention has predetermined chemical components, wherein in a region where a distance r from the center of a cross-section perpendicular to the length direction satisfies 0.7R?r?0.9R, structures include ferrite and bainite, the average fraction of the ferrite is in the range of 40 to 70% in terms of area ratio, the total average fraction of the structures other than the ferrite and the bainite is 0% or more and 3% or less on average, and the balance includes bainite; and the standard deviation of a ferrite fraction in the region is 4% or less.

Abstract: A three-dimensional model distribution method includes: distributing a first model, which is a three-dimensional model of a target space in a target time period, in a first distribution mode; and distributing a second model, which is a three-dimensional model of the target space in the target time period and makes a smaller change per unit time than the first model, in a second distribution mode different from the first distribution mode.

Abstract: A three-dimensional data encoding method includes: appending, to a bitstream, first information indicating whether a leaf to be included in an N-ary tree structure of three-dimensional points included in three-dimensional data is to include a single three-dimensional point or two or more three-dimensional points, where N is an integer greater than or equal to 2; when the first information indicates that the leaf is to include a single three-dimensional point, generating an N-ary tree structure in which a leaf includes a single three-dimensional point, and encoding the N-ary tree structure; and when the first information indicates that the leaf is to include two or more three-dimensional points, generating an N-ary tree structure in which a leaf includes two or more three-dimensional points, and encoding the N-ary tree structure.