Four-dimensional light field decoding preprocessing method based on original image

Abstract

The invention discloses a four-dimensional light field decoding preprocessing method based on an original image. The method comprises the step of utilizing a light field imaging device for collecting the original image of a scene, the step of calibrating the original image to obtain a center coordinate set of the original image, the step of carrying out re-sampling processing on the original image according to the calibration information to obtain a sub-aperture image array, the step of carrying out the vignetting removing processing on an edge sub-aperture image in the sub-aperture image array to obtain a sub-aperture image array with the vignetting removed, and the step of finishing the four-dimensional light field decoding through the sub-aperture image array with the vignetting removed to obtain the parameterization expression of a four-dimensional light field. The method breaks through the dependence limitation on a white image in the two key preprocessing steps of calibrating and vignetting removing in a traditional preprocessing method, the application flexibility of light field imaging is improved, the popularization application range of the light field imaging can be widened, and the method plays a positive role in promoting the application and development of the light field imaging.

Description

technical field [0001] The invention belongs to the technical fields of light field imaging, image processing, computer vision, etc., and relates to a four-dimensional light field decoding preprocessing method, in particular to an adaptive decoding preprocessing method independent of a white image. Background technique [0002] Light field imaging uses its special imaging structure to obtain four-dimensional light field data, significantly broadening the types of data captured by images, so it can also bring more information to image reconstruction. Currently, imaging depth of field, depth estimation, etc. field is applied. There are three main forms of light field imaging: microlens array, camera array, mask and others. Among them, the microlens array form obtains light field data through the microlens array placed between the main lens and the sensor, which is currently the most commonly used light field imaging method. [0003] Decoding the four-dimensional light field ...

AI Technical Summary

Problems solved by technology

The preprocessing of 4D light field decoding mainly includes calibration and devignetting. Calibration is to accurately locate the center position of each microlens image, and use the calibration information to perform accurate 4D light field decoding on the collected original light field images. However, The microlens array is not completely aligned with the sensor pixels, and there are offsets and rotations. Therefore, the 4D light field decoding process depends on the precise calibration of the light field camera. At the same time, the calibration information is not fixed, it will change with the camera The zoom of the lens changes, so calibration is the key to light field data processing, and it is also the bottleneck that restricts the flexibility of light field image processing

[0004] The current commercial lytro light field camera pre-stores nearly 50 white images with different parameter settings of the main lens. During the shooting process, a matching white image is found according to the parameter settings for decoding. The user experience is good but the lens cannot be replaced.

Raytrix can change the lens, but it is required to use a dodger to shoot a corresponding white image for preprocessing every time the lens is changed or zoomed in, which is less flexible than traditional SLR cameras.

Although these methods can achieve good results in the preprocessing of 4D light field decoding, they are still limited by the white image. When the light field camera changes the lens or performs operations such as zooming, it is necessary to re-acquire a new white image for use. Further data processing can only be carried out due to preprocessing, which greatly affects the flexibility of light field cameras and further limits the popularization and use of light field cameras.

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