45 results about "Topographic correction" patented technology

The invention relates to a multi-stereoscopic image fusion mapping method considering different illumination imaging conditions, comprising the following steps: 1) acquiring existing images in a research area, and selecting multiple coverage stereoscopic image pairs; 2) constructing an imaging geometric model of a remote sensing image; 3) ) carry out initial matching on the stereo image pair, and obtain the same-name point of the remote sensing image; step 4) carry out the beam adjustment of the stereo image area network on the imaging geometric model obtained in step 2), and obtain the refined imaging geometric model; 5) for each A group of stereoscopic image pairs is densely matched, and the set of image-space dense homonymous points of each group of stereoscopic image pairs is respectively obtained; 6) According to the refined imaging geometric model in 4), the image-space dense homonymous points obtained in step 5) are processed Intersection in front to obtain dense 3D point cloud of object space, and then obtain DEM through grid division and interpolation, and fuse DEM to obtain hole-free DEM; 7) Generate DOM according to hole-free DEM and refined imaging geometric model That is: an image with geographic information after terrain correction.

The invention discloses a novel vegetation index correction method that is resistant to terrain effects and background effects, including A collecting remote sensing images and DEM data of vegetation; Correction to obtain the surface reflectance; C calculate the vegetation index NIRv and terrain correction factor P corresponding to each pixel according to the slope data and surface reflectance; use the vegetation index NIRv and terrain correction factor P as input to calculate the anti-topography vegetation index. The method for correcting the original vegetation index by introducing a terrain correction factor proposed by the present invention has strong universality, strong resistance to terrain and the ability to characterize vegetation structure, and is expected to further improve the application potential of the vegetation index in mountainous areas.

The invention relates to an improved physical method for topographic correction of remote sensing images, which considers the influence of the topography on incident irradiance and earth surface reflectivity received by the sloping surface, more accurately computes sky radiation received by the sloping surface pixel, and meanwhile considers the influence of atmosphere during the topographic correction. The method of the invention can obtain the better result of the topographic correction; and the method belongs to the physical method, has universality and can be applied to various optical remote sensing images.

The invention discloses a ratio method for correcting topographic influence in electromagnetic prospecting. The ratio method comprises the steps of acquiring a surface layer resistivity value without topographic influence to serve as a standard resistivity of topographic correction; drawing an in-line topographic profile, respectively comparing the topographic profile with a frequency point profile of a frequency domain electromagnetic method and a time channel profile of a time domain electromagnetic method, and judging the topographic influence suffered by the actually measured data according to the influence rule of the topography on the resistivity in the frequency domain and the time domain electromagnetic field; observing from the highest frequency point of the frequency domain electromagnetic method and the earliest time channel of the time domain electromagnetic method so as to obtain the topographic response which is closest to the surface layer until the absence of low-frequency frequency point of the topographic influence is observed in the frequency domain electromagnetic method and the absence of the late time channel of the topographic influence is observed in the time domain electromagnetic method, and acquiring the observation data without topographic influence; and performing topographic correction according to a ratio formula of pcorrected(i,j)=pmeasured(i,j) [pstandard(i) / pmeasured(i,l)]C(i,j). The ratio method is good in correction effect in the process of correcting the topographic influence, is high in feasibility and can be widely applied to topographic influence correction in electromagnetic prospecting.

The present invention discloses a terrain correction method for a remote sensing image based on micro terrains, which comprises the following steps: registering the remote sensing image and DEM (dynamic effect model) data at first and determining the number of the micro terrains in each element of the remote sensing image; calculating the slope and the slope aspect of each micro terrain and the incidence angle and the observation angle according to the DEM data, the azimuth of the sun and the azimuth of a sensor, and calculating the projection and radiation factor of each micro terrain on thehorizontal plane and the shadowing factor of adjacent micro terrains on each micro terrain; and finally, calculating the total projection and radiation factor of each element of the remote sensing image according to the projection and radiation factor of each micro terrain on the horizontal plane, the shadowing factor of the adjacent micro terrains on each micro terrain and the number of the micro terrains in each element of the remote sensing image, and carrying out terrain correction for the original remote sensing image. By adopting the shadowing effect of the adjacent micro terrains on each micro terrain, the accuracy of the terrain correction for the remote sensing image can be increased.

The invention discloses a metric wave radar terrain correction method based on a digital elevation model, which belongs to the technical field of metric wave radar signal processing. There is a flying target within the detection range of the metric wave radar; obtain the digital elevation model data, and determine the ADS‑B data of the flying target, and then determine the important reflection points in the spherical coordinate system; ‑B data and determine important reflection points, obtain the results of the correlation between the ADS‑B data of the flying target and the metric wave radar terminal data, and then obtain the altitude curve of the flying target; The metric wave radar altimetry error curve is corrected, and the final error correction result is obtained as a topographic correction result of the metric wave radar based on the digital elevation model.