Correcting ARGI red band to enhance RGB composition

In order to synthesize better true color images of AGRI on FengYun-4B. Another researcher suggested making a red band correction instead of using ABI compose solution. It is because the Band2 spectral interval of AGRI is different from ABI. Use the following Band math formula to correct it (C02-0.13*C03)/0.87 FY-4B_true_color_corrected FY-4B_true_color_original

Thanks for the info. It would be good to have a more physically based approach, as we talked about in the last few days @mraspaud, that is based on the spectral response function. As that is a larger job and appropriate to multiple satellites I think that's a separate issue. My suggestion is that I add this 'quick fix' to FY-4/AGRI now and then we can revisit once we have a more generic technique in the future. :-)

Sounds good to me!

@MengXin001 do you have any documentation or literature that describes this correction? It would be good to include this information in the code for future reference.

@simonrp84 SRFs on NSMC's PPT, the Channel02 of AGRI is similar to a panchromatic band, and NSMC mentioned Red Channel compensate in their PPTs on CGMS-50 (without detailed method). I tried many times for red channel comensate after the FY4B data was released then got this formula ((Band2-0.13*Band3)/0.87) to correct the red band.

@simonrp84 That is exactly using the method from @WP19VFF