Kanopus-V, BKA primary processing
Primary processing technology for Kanopus-V1 and BKA data within IMC software is fully automated and consists of following steps:
|Georeferencing improvement using reference points.
|Georeferencing error in degrees.
|Obtaining DEM for scenes geometric correction (GMTED 2010, 250m).
|DEM in IMG file format
|RPC-transformation of micro-frames considering the error estimated during stage 1.
|Transformed spectral bands in IMF file format
|Formation of spectral bands out of micro-frames
|5 bands (4 multispectral + PAN) in IMG format
|Eliminating offset between 4 spectral bands and panchromatic band. Formation of 4 multispectral bands image.
|File in IMG format
|Panchromatic image resolution improvement.
|Resolution increase by 10-12%
|Formation of pansharpened RGB image in natural colors with resolution of panchromatic image.
|File in IMG format
|Noise elimination, Signal/noise ratio before processing = 10 dB.
|Signal/noise ratio after processing = 13 dB.
|Georeferencing accuracy and image resolution evaluation.
|Georeferencing accuracy ~ 10m
Set the path to the input data;
Set the path where the output data will be saved;
Set the path to the DEM file;
Press “Start” button.
As an input data level 1 data is used ( sets of separate micro-frames for different spectral bands of a single scene with RPC, w/o radiometric correction, w/o orthorectification).
On this stage orthorectification of the micro-frames using digital elevation model and RPC and correction to UTM (WGS84) map projection are performed. Before the automated orthorectification process is begun, georeferencing error can be calculated for several micro-frames. Optionally, the coordinates of reference points can be set for more accurate georeferencing improvement.
On this stage separate micro-frames are being stitched into color bands. Innovative radiometric correction algorithm makes it possible to effectively eliminate brightness difference between micro-frames. As a result of the processing 5 files in IMG file format are created (4 for each multispectral band and 1 for panchromatic band).
On this stage offset between 4 spectral bands and panchromatic band is eliminated. As a result of the processing 5 files in IMG file format are created (4 for each multispectral band and 1 for panchromatic band)
- level 2A data (panchromatic image with radiometric and geometric correction, orthorectified and corrected to the map projection to an average elevation value according to the on-board automatic navigation system with standard deviation not greater than 50 m);
- level 2A1 data (multispectral image of the 4 spectral bands (RGB+IR) with radiometric and geometric correction, orthorectified and corrected to the map projection to an average elevation value according to the on-board automatic navigation system with standard deviation not greater than 50 m);
- level 4A data (pansharpened RGB image in natural colors with resolution of panchromatic image);
- metadata in XML format for each image;
- scene borders in SHP format.
Level 2B, 2B1, 4B output data can be obtained with the help of additional reference data and DEM (accuracy of output data depends on the accuracy of reference data) .