8 results about "Shadow casting" patented technology

The utility model relates to the technical field of film detection, in particular to a film defect detection device. The device comprises a film viewing cavity arranged in a darkroom, the film viewing cavity comprises a main cavity defined by baffles and a middle platform layer arranged in the main cavity, a light through hole is formed in the middle platform layer, a xenon lamp is installed at the top of an upper cavity so that light can irradiate a to-be-detected film at the light through hole, and a defect imaging curtain is laid at the bottom of a lower cavity so that the to-be-detected film can be detected. The shadow left by the thin film at the light through hole is received; light penetrates through the thin film, shadow is projected on the defect imaging curtain laid at the bottom of the lower cavity, due to the fact that the xenon lamp with higher light penetrating power is selected, slight deformation type defects of the thin film can be seen on the defect imaging curtain, the defects of an existing thin film defect observation mode are overcome, and the tiny and slight deformation type defects of the thin film can be seen.

To improve the accuracy of light source position detection. [Solution] The light source position detection method includes illuminating the jig 10 with a light source Li such that the shadows 15 of each sphere 14 of the multiple protrusions 12 are projected onto the base 11; capturing multiple images of the jig 10 illuminated by the light source Li with multiple cameras C; calculating a first three-dimensional coordinate X1 of the center of the sphere 14 and a second three-dimensional coordinate X2 of the center of the shadow 15 of the sphere 14 for each of the multiple protrusions 12 based on the multiple images; calculating multiple light source vectors V for the multiple protrusions 12, wherein each of the multiple light source vectors V passes through the first three-dimensional coordinate X1 and the second three-dimensional coordinate X2 for each of the multiple protrusions 12; and calculating the position of the light source Li based on the multiple light source vectors V.

A method for checking dimensions and geometrical features of a mechanical part using an optoelectronic system of the shadow casting type includes calculating the spatial coordinates of points of the surface of the part that allow a 3D reconstruction of the surface of the part, and checking the dimensions and geometrical features making use of such spatial coordinates. The spatial coordinates of the points are calculated starting from two-dimensional images and relevant profiles obtained by means of the shadow casting system while the mechanical part rotates about a rotation axis. The position of points or edges of the profiles and variation of such position are detected at predetermined heights as the rotation angle varies. On the basis of such variation, the position, with respect to a measurement plane, of points on the part to be checked which generate points of the aforementioned profile is identified and the spatial coordinates of the points of the surface are calculated.

Methods and apparatuses for controlled shadow casting to increase perceived quality of projected content are disclosed. In some examples, an apparatus is for increasing perceived quality of content projected onto a projection surface. In some examples, the apparatus includes a shutter position determiner to determine a target shutter position of a shutter based on a position of a light source and a position of the projection surface. In some disclosed examples, the apparatus further includes a shutter controller to move the shutter to the target shutter position to cast a shadow onto the projection surface around a portion of the content projected onto the projection surface.

The application provides a vehicle 3D model light rendering method, system, electronic equipment and medium, and belongs to the technical field of vehicles. The method comprises the following steps: acquiring an aerial panoramic image collected by a surround-view camera; processing the aerial panoramic image to obtain a binary mask for marking a shadow area of a vehicle; performing main light source parameter estimation based on a vehicle 3D model, the aerial panoramic image and the binary mask to obtain a main light source parameter set; determining an ambient light parameter based on the aerial panoramic image and the binary mask; and performing 3D vehicle model rendering based on the main light source parameter set, the ambient light parameter, the vehicle 3D model and the aerial panoramic image. The application uses the shadow projected by the vehicle itself as an information source for light perception, realizes closed-loop light perception and can adapt to complex scenes. Through accurate light source direction calculation and full parameter estimation, the application provides a mathematical basis for generating correct shadow projection and mirror reflection effects, and significantly improves the realism of rendering.

The invention discloses an asymmetric illumination three-dimensional face reconstruction method and system based on a monocular camera, relates to the field of face image reconstruction, and completes initial estimation of a face by acquiring initial three-dimensional parameters and depth features of the face through an encoder and a regression network. And subsequently introducing a double-branch detail refining network to decouple and refine mutually coupled surface attributes and illumination information, and respectively outputting high-frequency geometric details, a refined albedo map and refined illumination parameters. In a final analysis-synthesis link, a rendering pipeline containing micro shadow projection is adopted. By explicitly simulating the process of generating the projection shadow by geometric shielding during rendering, the shadow can be correctly reproduced by the synthetic image. Therefore, the model can be guided to jump out of a local optimal trap, and precise separation and high-fidelity reconstruction of geometry, texture and asymmetric illumination are realized.

The embodiment of the invention discloses a roof photovoltaic intelligent arrangement method and system based on shadow analysis and region cutting. The method comprises the following steps: identifying a three-dimensional model of a building and a shelter; according to the geographic position and the sunlight parameters, performing three-dimensional shadow analysis by adopting a shadow projection algorithm to obtain a shadow area on the to-be-laid surface of the roof; identifying a roof contour and determining a to-be-laid area; geometric Boolean subtraction is carried out on the to-be-laid area and the shadow area, and an effective laying area is obtained through cutting; and automatically generating a photovoltaic panel arrangement scheme in the effective area according to preset parameters. According to the method, general accurate analysis of a flat roof and a pitched roof, automatic avoidance of a shadow region and full utilization of a laying area are realized, and the automation degree, accuracy and economical efficiency of photovoltaic arrangement design are remarkably improved. The problems of inaccurate arrangement, low efficiency and poor economical efficiency caused by the fact that three-dimensional shielding shadows on complex roofs cannot be accurately calculated and dependence on manual judgment in the prior art are solved.

The application discloses a real-time dynamic light rendering optimization method based on Unreal Engine, and relates to the field of light rendering. Firstly, based on a camera view cone and AI context data, shadow importance scores are assigned to each mesh object in a scene, and potential shadow casters are prioritized. Then, performance budget evaluation is performed in combination with the current frame rate and GPU load, and intelligent shadow projector selection and LOD application are performed on the sorted shadow caster list accordingly. Finally, these optimized rendering shadow batches are sent to the light perspective rendering and VSM page filling processes to generate movable light source optimized virtual shadow. This method significantly reduces unnecessary computational overhead, thereby greatly improving rendering efficiency and frame rate stability while ensuring high-quality dynamic light effects, effectively solving the core problem of balancing traditional performance and quality.