TIN-based orthoimage splicing color consistency processing technology

Abstract

In order to obtain high-quality Digital Orthophoto Map (DOM), consistency processing of colors between images in the production process of the DOM is an indispensable technical link. In order to simplify a color processing step and further optimize an image uniform light and color effect, the invention discloses a consistency processing technology of colors between orthoimages on the basis of Triangulated Irregular Network (TIN). According to the technology, on the basis of image light-uniforming processing, through combinations with a mosaic line and an image after light uniforming, a target gray average and a variance of images are interpolated on the basis of the TIN, and then color consistency between the images is achieved by utilizing a Wallis conversion. Through a lot of experiments, an algorithm can obtain an ideal color consistency processing effect, extra overlap area color consistency processing are not needed after light- and color-uniforming processing; and the color consistency processing step is simplified, the whole processing does not rely on an external reference image, and the automatic degree of the color consistence processing is further improved.

Description

technical field [0001] Surveying and Mapping Science and Technology Background technique [0002] As one of the 4D products in the surveying and mapping industry, Digital OrthophotoMap (DOM) can intuitively and vividly reflect the status of terrain, landforms, and features. It is the basis for making topographic maps and establishing national basic information databases. It is used in urban planning, The construction of water conservancy and hydropower facilities, general survey of land and resources, disaster relief, monitoring of changes in land resources, national security and defense, etc. are playing an increasingly important role in applications related to the people's livelihood and development of the country. [0003] The production process of orthophoto products mainly includes three steps: geometric correction, color consistency processing and mosaic. Among them, the color consistency processing is to eliminate the influence of camera parameters, inhomogeneity of ...

AI Technical Summary

Problems solved by technology

However, after uniform color processing, there will still be high-contrast areas such as bright spots and dark spots in the resulting image

In 2009, Sun Mingwei proposed the area network color uniform method based on the principle of least squares. Although, like many scholars, the factor of overlapping areas is considered, it is still necessary to manually formulate a selection plan to control the overall color quality in the survey area. control

However, the difference in the control image selection scheme will have a great impact on the overall tone of the image in the survey area

Images