[FFmpeg-user] Fluorescent White Balance Video Filters

[Roger]

>> Found through Google,
>> https://lutify.me/free-white-balance-correction-luts-for-everyone/
>> Download: Free White Balance Correction LUTs
>> Lutify-me-Free-White-Balance-Correction-3D-LUTs.zip
>> 
>> 2800 Kelvin - 3200 Kelvin - 0.34 CTO.cube
>> 2800 Kelvin - 4300 Kelvin - 0.95 CTO.cube
>> 2800 Kelvin - 5500 Kelvin - 1.34 CTO.cube
>> 2800 Kelvin - 6500 Kelvin - 1.56 CTO.cube
>> 3200 Kelvin - 2800 Kelvin - 0.34 CTB.cube
>> 3200 Kelvin - 4300 Kelvin - 0.61 CTO.cube
>> 3200 Kelvin - 5500 Kelvin - 1.00 CTO.cube
>> 3200 Kelvin - 6500 Kelvin - 1.21 CTO.cube
>> 4300 Kelvin - 2800 Kelvin - 0.95 CTB.cube
>> 4300 Kelvin - 3200 Kelvin - 0.61 CTB.cube
>> 4300 Kelvin - 5500 Kelvin - 0.39 CTO.cube
>> 4300 Kelvin - 6500 Kelvin - 0.60 CTO.cube
>> 5500 Kelvin - 2800 Kelvin - 1.34 CTB.cube
>> 5500 Kelvin - 3200 Kelvin - 1.00 CTB.cube
>> 5500 Kelvin - 4300 Kelvin - 0.39 CTB.cube
>> 5500 Kelvin - 6500 Kelvin - 0.21 CTO.cube
>> 6500 Kelvin - 2800 Kelvin - 1.56 CTB.cube
>> 6500 Kelvin - 3200 Kelvin - 1.21 CTB.cube
>> 6500 Kelvin - 4300 Kelvin - 0.60 CTB.cube
>> 6500 Kelvin - 5500 Kelvin - 0.21 CTB.cube
...
>> Are these LUTS my best options?  Or does the paid subscription offer better?
>> Or are there other white balance/color correcting LUTS elsewhere?
>

Think I figured-out, the previously listed kelvin cube files above, seem to be 
a compilation of gradual generic tint lut/cube files.

>You can make your own LUT, as described in chapter 2.28 in my book.
>-- Extract one frame from your video.
>-- Insert a haldclut in a corner of the image, or use xstack to attach it to
>the side.
>-- Use the program of your choice to correct the colors in this image. When
>done, save it lossless as 16-bit PNG.
>-- Use FFmpeg to separate the haldclut from the image.
>-- Apply the LUT to the whole video.
>
>Michael

Sorry.  I had a little difficulty with understanding the text within the 
Chapter 2.28.  Just couldn't scan and understand easily.  Although I thoroughly 
understand SH/Bash, the variable assignments for simple filenames also slowed 
reading, as I had to scan/reference back to the top of the page for the 
definition/intent of the variable used.  Easier understanding for the reader to 
read, "input_video.ext" and "output_video.ext", or use a similar named variable 
such as $_input_video.ext and $_output_video.ext. Note: using a prefixed 
underscore within SH/Bash variables separates/isolates from any possible 
conflicts.  Heard of using this syntax from the Bash mailing list when doing C 
style defines in SH/Bash.  However, for the sake of easy readability for 
readers, it's probably best to use simple non-isolated variables.

Some of the terminology used at this chapter is above my head, but I've been 
looking to do something exactly as you described when using my Nikon D5600 when 
taking raw photos and attaining similar results to it's Capture NX-D/Studio.

I've flagged this Email and will hopefully return to it when I get more free 
time.  I waste a full day on these larger tasks, especially on first time 
workflows.

Don't worry, I did figure-out how to apply LUTS, either from the chapter or 
from additional Google searching for ffmpeg Stack Exchange examples, etc.

Roger