Three-line-array stereo aerial survey camera parallel spectrum band registration method based on GPU technology

Abstract

The invention provides a three-line-array stereo aerial survey camera parallel spectrum band registration method based on GPU technology. The method comprises the following steps: 1) carrying out convolution on an original image I(x,y) at the GPU end, establishing Gaussian pyramid L (x, y, sigma) parallelization and establishing Gaussian differential pyramid D(X,Y, sigma) parallelization; 2) carrying out line convolution on gray images at the GPU end, and then, carrying out row convolution, and reducing algorithm complexity from O (N<2>) to O (N); 3) under the condition of storage space continuity, carrying out extreme point number accumulation storage to ensure that only one thread operates accumulation address at the same time; 4) binding texture registers and setting one CUDA thread for each key point; 5) generating a multidimensional descriptor, and utilizing one thread block to process multi-dimensional vector of one feature point; and 6) carrying out KD-tree construction at a CPU. Through actual test, processing resolution can reach or be higher than 16378*8192; the method based on GPU technology solves the speed difficulty in carrying out real-time image registration on super-resolution images; the registration time is in a millisecond level; and the method can be applied to an aerial survey camera image processing system easily.

Description

technical field [0001] The invention belongs to the technical field of parallel computing image processing in the image processing of a three-line array aerial survey camera, and in particular relates to a super-high resolution parallel spectral segment registration method for aerial survey cameras based on GPU technology. Background technique [0002] With the continuous development of aerial survey camera technology, the increase of image size and the improvement of spatial resolution, more useful image information can be extracted from high-resolution images. At present, most of the better methods for image registration are mainly used in the registration of small and medium-sized images, and ignore the time performance, and lack the processing and application of large-scale image data. Super-resolution image processing of cameras, especially the bottleneck faced by emergency image processing within a limited processing time. [0003] At present, feature detection and re...

AI Technical Summary

Problems solved by technology

The grayscale-based method directly uses the grayscale information of the image, and finds the matching parameters with the largest similarity based on the optimization criterion, without complex image preprocessing. Technical characteristics of super high resolution

The method based on the change domain uses fast algorithms to increase the speed, such as the Fourier fast algorithm, but its application is limited to relatively simple transformation forms such as scaling and translation. For complex transformation methods such as affine transformation or projection transformation, the application The effect is not good, and it cannot adapt to the rich image transformation characteristics of aerial survey cameras

[0004] However, the two types of detection and matching methods based on feature points have bottlenecks in calculation speed. When the image size is large or a large Gaussian smoothing window is used, the calculation speed is significantly reduced, and the cumbersome algorithm increases the burden on computer hardware. The CPU processing method can no longer meet the application of this type of method, and a large amount of matching feature data consumes a large amount of storage space and time

In addition, the high complexity of the algorithm severely limits the application of this type of matching method in the field of real-time image processing.

Although the research shows that the feature point-based algorithm based on GPU can speed up the image registration process, but there is no registration result for super-resolution aerial cameras

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