Method and equipment for drawing shadow of virtual object

Abstract

The invention relates to the technical field of AR, and provides a method and equipment for drawing a virtual object shadow, and the method comprises the steps: employing an HDR panoramic image to generate a model, obtaining an HDR panoramic image corresponding to an LDR image of a real scene, taking the KL divergence as a loss function, employing the HDR panoramic image to carry out the fine tuning of an illumination spherical harmonic feature model, optimizing the original spherical Gaussian intensity distribution of the illumination spherical harmonic feature model, and obtaining the shadow of a virtual object. The training process of the illumination spherical harmonic feature model is saved, and time and labor are saved; the point with the maximum brightness value in the optimized spherical Gaussian intensity distribution is determined as the light source position, and the shadow is drawn for the virtual object displayed in the LDR image according to the light source position. Because the HDR panoramic image completely records the environment illumination information and the real spherical Gaussian intensity distribution including the environment illumination, the accuracy of determining the light source position is improved, the drawing effect of the virtual object shadow is improved, the illumination consistency of the virtual object and a real scene is further improved, and the AR experience of a user is improved.

Description

technical field [0001] The present application relates to the technical field of Augmented Reality (AR), and in particular, to a method and device for drawing shadows of virtual objects. Background technique [0002] AR technology is a new technology developed on the basis of virtual reality (VR). It is a technology that increases the user's perception of the real world through the information provided by the computer system, and combines the virtual objects, virtual scenes and system prompts generated by the computer system. Information or non-geometric information about real objects are superimposed into the real world, so as to achieve "enhancement" of the real world, which has been widely used in all walks of life. [0003] In AR experience, users have a subtle sense of lighting, and usually use lighting consistency as an important indicator of virtual-real fusion. Lighting consistency refers to making virtual objects have the same lighting effect as real objects. The g...

AI Technical Summary

Problems solved by technology

However, since the original image collected by the camera of the AR device is generally a Low Dynamic Range (LDR) image, which contains less illumination information, the estimation of the position of the light source is not accurate enough, which in turn reduces the illumination of the virtual object and the real scene. Consistency, affecting user AR experience

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