Compressed DNG support?


(tommy) #1

It would be of great benefit to those of us doing cinema work with rawtherapee if you enabled support for compressed DNG files. It would not only save hundreds of gigabytes of storage space, but also remove the extra step of having to decompress the source footage just to load into rawtherapee!

Thank you!


(Morgan Hardwood) #2

@70MM13 please upload a sample raw file to https://raw.pixls.us/ or https://filebin.net/ and link it here.


(tommy) #3

Uploaded sample to your database, but am unable to provide link. I tried unsuccessfully to find a way to do so. Sorry, it may be a phone browser issue. I’m sure you will be able to find it! I described it as something like “compressed dng sample frame”

Thanks.


(Morgan Hardwood) #4

Thanks for uploading @70MM13, @LebedevRI found it:
https://raw.pixls.us/getfile.php/2204/nice/Canon%20-%20EOS%205D%20Mark%20III%20-%2014bit%20(2.3471882640587).dng


(Morgan Hardwood) #5

Opened issue #4285


(Jed Smith) #6

I would love to see compressed cinema dng support added to RawTherapee as well. I’ve added a few more example images, and some information that might be helpful on the issue:

Thanks!


(tommy) #7

Yes!

It’s badly needed!


(Mica) #8

I wonder if @LebedevRI has an interest in supporting this in rawspeed?


(Roman Lebedev) #9

Unlike GoPro, this would be kinda trivial.
Basically, you would “only” need to change


That is prediction, where the previous pixel is the only pixel used for prediction, i.e. mode 1.
CinemaDNG uses different prediction scheme, mode 6. (last time i checked?)
See https://en.wikipedia.org/wiki/Lossless_JPEG#Lossless_mode_of_operation for the modes explainations.

The downside of that is combinatorial explosion…

So TLDR: yes, but not yet.