Is there a way to import a Hald CLUT into MLVApp to create LUTS?

[zineorg]

I've been trying to import a Hald CLUT for a few days to be able to create my LUTS from the MLVApp itself. I have generated a TIFF image of the Hald with ImageMagick, for example:

convert hald:10 -depth 16 -colorspace sRGB hald.tif

And then I tried to convert it to DNG so I can create an MLV file with raw2mlv. First by following the experimental trick from this Rawtherapee RawPedia article, where they change the EXIF to "convert" the TIFF to DNG:

convert hald:12 -depth 16 -colorspace RGB -gravity NorthWest -splice 4x4 -gravity SouthEast -splice 4x4 foo.tif
exiftool -DNGVersion=1.4.0.0 -PhotometricInterpretation='Linear Raw' foo.tif
mv -v foo.tif Hald_CLUT_Identity_12.dng

The DNG generated by this method did not work with raw2mlv. Then I tried the Adobe DNG Converter program, but it doesn't recognize either the DNG or the TIFF. Is there a way to get a .MLV with a single frame from a Hald? From what I've read, people got it by simply converting the Hald image to DNG using Lightroom or Photoshop (unfortunately I don't know anyone who has these Adobe programs and the links to download these generated DNGs are down).

I think this would be useful to create our own LUTS from the MLVApp itself, since having the modified Hald with the color receipt applied, it is just a click of a button to generate the .cube in G'MIC or in any LUT Converter on Github.

[ilia3101]

It didn't convert to MLV because that's RGB data, and the MLV format and MLV App's rigid architecture only support bayer data, so there's no chance of getting this in to MLV App. Unless you somehow generate bayer data that, once demosaiced, produces exactly those values. But why would you even want an MLV App based LUT? Why not just use Arri K1S1 or something?

[zineorg]

It would be to create our own final LUTs using the MLVApp interface, without having to go out and edit colors of a frame in Gimp, Davinci or such, to apply those colors to the Hald and be able to generate the cube file. In this way I have achieved it without problems with GIMP, but I prefer the MLVApp interface (besides the fact that when exporting a frame from MLVApp it already changes the color slightly, due to the export format I suppose).

With the Arri K1S1 lut you get Rec709, but I would like to generate my own final color scheme and be able to carry it from shot to shot regardless of the shooting conditions. For example, if I save a receipt in MLV, it saves me that all blues +8, regardless of whether some shot is already very blue. With the LUT you could tell it that all blues "look like this", regardless of their initial intensity. That is the utility that I see, but it seems difficult to achieve... I will keep trying, there has to be a way since the people of Rawtherapee shared those Hald in DNG fully functional! Too bad the links have expired.

[zineorg]

Well, it seems that there are possibilities (although it involves work that is not worth the effort, especially when editing the bayer pattern). I have managed to manipulate a RAW DNG passing it to TIFF with the bayer mosaic with DCRAW. Then this TIFF is editable in GIMP as long as the bayer pattern is respected, then the DNG is "built" again from the altered TIFF with the help of exiftool and dng_validate.

Thanks to Guillermo Luijk's script. In the image a modified DNG (by Guillermo himself as an example, since my modified DNGs are not pitiful) imported into MLVApp through raw2mlv. Then getting a HALD Clut that after demosaicing maintains its integrity and is usable seems like a very difficult task.

[2blackbar]

You tried topaz jpg to raw ? I tried it but without luck, it creates dngs but they didnt work in raw2mlv , maybe they need to be reconverted several times to work.
I wanted to create a LUT that mimics reinhard tonemapping from mlvapp

[zineorg]

You tried topaz jpg to raw ? I tried it but without luck, it creates dngs but they didnt work in raw2mlv , maybe they need to be reconverted several times to work. I wanted to create a LUT that mimics reinhard tonemapping from mlvapp

Great idea! If you share the DNG Hald I can try to convert it to MLV. I'm trying to install Topaz from a virtual machine (since I use linux) at the moment without success, but I think if I could transform that DNG to MLV!

I also want to experiment with creating a LUT from the MLVApp itself, although we must bear in mind that it may not work perfectly due to the nature of the RAW file and its demosaic. Who knows, it might work just fine!

[2blackbar]

lut.zip
Heres dng , i dont like that its so compressed, even if it works, it wont look good and this program wont accept dngs, youd need probably 800%scale jpeg and scaling down