satdump/resources/scripted_compos/split_difference.lua
2024-05-02 21:10:39 -04:00

53 lines
1.7 KiB
Lua

-- Split Difference
function init()
--create an empty image for the LUT
img_lut = image8.new()
--load the LUT
img_lut:load_png(get_resource_path("lut/cal/abi_split_difference.png"), false)
--return 3 channels, RGB
return 3
end
function process()
for x = 0, rgb_output:width() - 1, 1 do
for y = 0, rgb_output:height() - 1, 1 do
--get channels from satdump.json
get_channel_values(x, y)
local cch13 = get_channel_value(0)
local cch15 = get_channel_value(1)
--perform Difference, scaling -10 - 10 to 0-1
local difference = (cch13-cch15+0.07299270072)/0.14598540146
--range convert from 0-1 to 0-255
local lutval = difference*255
--sanity checks
if lutval < 0 then
lutval = 0
end
if lutval > 255 then
lutval = 255
end
--don't forget to create a table!
local lut_result = {}
--send the lutval to the LUT, retrieve it back in the table as 3 R,G,B channels
lut_result[0] = img_lut:get(0 * img_lut:height() * img_lut:width() + lutval) / 255.0
lut_result[1] = img_lut:get(1 * img_lut:height() * img_lut:width() + lutval) / 255.0
lut_result[2] = img_lut:get(2 * img_lut:height() * img_lut:width() + lutval) / 255.0
--return RGB 0=R 1=G 2=B
set_img_out(0, x, y, lut_result[0])
set_img_out(1, x, y, lut_result[1])
set_img_out(2, x, y, lut_result[2])
end
--set the progress bar accordingly
set_progress(x, rgb_output:width())
end
end