color workflows in (open source) video editing

Software
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Short version: For someone used to raw workflows with photos, what would be a good direction to explore with video, if open source is a requirement?

Medium version: If I’m recording in a log space (Panasonic v-log), is there an open source video editor that can handle things like 3d luts, provides a well-defined color pipeline that preserves 10-bit color or better until export and includes an array of tools comparable to what we’re used to in photo editors?

Long-winded story version:

If anyone has any ideas, I’m all ears. I’ll start asking in more video-centric places next, but I felt the Pixls crew would better understand my context starting out.

Before now, I’ve never given video color all that much thought, even though my favored camera brand (Panasonic Lumix) leans heavily into the video features of its camera bodies. The video I did take was just the style of “home video” I remember from the 1980s and 90s: unedited, ungraded, useful memories of moments with the family.

spektrafilm-lut from the Spektrafilm project has slowly changed that for me. I’ve started exploring the freedom that recording in a 10-bit log space affords, and it’s been the kind of fun I normally only get with raw photos.

My videos? They’re pretty bad. Video is a different set of skills that I don’t have yet. :rofl:

But what I’m really curious about right now is color grading. I started with Kdenlive for some airshow footage I took, and had quite a difficult time adjusting things like exposure without pink and cyan artifacts in thin background clouds. I didn’t find out until later that Kdenlive does all of it’s editing in 8-bit (!) color. :frowning:

Shotcut does better, but the actual tools available feel pretty basic compared to what I’m used to. I’ll spend more time on their forum to get specific questions answered, but that’s my impression so far.

DaVinci Resolve is free, but not open source, so the only thing I’ll say about it is that I want to exhaust all other options first.

Finally, there’s Blender. If someone advises me that it can do what I’m asking, I’ll try to figure it out, but that one makes darktable seem quite beginner friendly in comparison.

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Hi @BorisRabit

I did a couple of videos last year with Kdenlive. I had some challenges with color banding due to 8-bit processing. I switched to Resolve and haven’t looked back.

Improving the color pipeline for Kdenlive may be on the roadmap, but I got the impression from the user forum was that there was no concrete timeline.

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Yeah, I’ve switched to Shotcut for now as it seems to have a more robust pipeline. It just doesn’t have the advanced tools that Resolve does.

It feels ironic that open source seems to out-do commercial offerings with color controls for photography, but I haven’t seen it with video. I’d rather not use Resolve.

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Sure, I understand that.

While Resolve is a commercial product, I appreciate what the owner of Blackmagic Design has done to democratize it. In the “old days” it was mostly just for color grading and cost tens of thousands of US$ for a license. Now it is a far more capable product, with a free tier that covers >90% of the features, and a full license is ~US$300. So far the company has given version upgrades at no added cost.

As a commercial entity, it is always possible it will be bought by “EvilCorp” and ruined. But for me all is good for now.

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Don’t know if it has the tools you want, but vkdt can also process video.

KDEnlive has 10/12bit support on the roadmap for 26.08, but, looking at the tracking issue, that seems optimistic.

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Thank you. Is there a guide for this? I’m having trouble finding one, and getting this to work hasn’t been obvious to me.

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I don’t think so, and I haven’t tried it myself, so no idea on the details. @hanatos ?

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Much depends on what formats the video editors support. I believe vkdt only supports open source formats, which really limits what you can do with it, since all the big commercial players like blackmagic, arri, Sony, etc… have their own formats. Someone correct me if vkdt can in fact edit those files, it’s been a while since I’ve looked into it.

There was a video editing app called olive that seemed very promising, but development stagnated, so I’m not sure where it’s at now.

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One can use ffmpeg to transcode video formats. I used this with the free version of Resolve to import my HEVC 4:2:2 log footage, transcoding to ProRes first. ProRes is supported in the free edition.

But I failed to find something that works with i-vid (used in vkdt). Perhaps someone else knows a way.

IF this could be made to work, one could color grade clips in vkdt, exporting in 8-bit format, and do general video editing in Kdenlive. Kdenlive is a capable video editor.

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There is cinelerra : 16 bits video and GPL according to wikipedia.

I think I used it a (very) long time ago, but too complicated for my use.

I use KDEnlive for my personal use, easy enough for 2 to 3 times a year :rofl:

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i-vid uses FFmpeg, so in theory any codec supported by FFmpeg should work.

This is a good tool for converting to different formats:

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I have done quite a lot of video editing of short films some years ago.
My journey was through all the usual open source suspects: cinelerra, kdenlive, lives, openshot, shotcut, flowblade and so on.

In the end, they were all nice for editing 8-bit video recorded in gamma-corrected color.
But when 10-bit with Log-Encoding emerged, those tools (except maybe cinelerra) were just not usable for me as they lack(ed) a proper color management workflow supporting high bit depths internally. The transformation from log space to srgb alone does not work without artifacts when computing in 8 bit - even with no other color correction.
Also, I like a node-based workflow for color correction and want to work in scene-referred space here, especially for compositing.

In the end, I ended with Blender and were quite happy with it!
One has to get used to the UI, but as soon as you have customized it to your needs, it is very capable and you can edit quickly.
The color management pipeline is production grade.
It still struggles with performance in some aspects.

Back then I made (together with other devs) some plugins for blender that worked around some limitations of the workflow - in particular:

  • preview of video files before adding them to the timeline, with trimming support
  • interface to use darktable for color correction
  • using blender’s node compositor for color correction

https://wilecoyote2015.github.io/Blender_Addons/

Those addons are outdated and probably incompatible now.
But most of this functionality is now present in vanilla blender as far as I know!

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that^. i have successfully opened mp4/mov with 10 bits and bt2020/pq as well as pana-v (detection normally works out of the box, does not convert to 8-bits in between).

that said, vkdt has a gpu decoder for mcraw but uses ffmpeg/software to decode the rest. i want to look into vulkan video decoding (using ffmpeg) that should make working with 4k@60 much more fluent. now it’s hardly usable with heavy formats.

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Good to know, thank you.

I might have a configuration issue on my end. When I tried opening HEVC 4:2:2 Vlog-L from my Lumix G9, the format wasn’t recognized. Same result for the same clip transcoded to ProRes.

But I don’t need a solution for myself; I was just curious.

Thanks for such an awesome project! I’ve dipped my toes into vkdt for photo editing with filmsim. It’s wonderful! :grinning:

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let me know if you hit a blocker with some relevant file, i can take a look and probably make it work. i really want the hardware decoding though, which will require GPU hardware support. not much fun editing video without that anyways.

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Oh boy. The on-ramp is so steep I feel like I need rock-climbing gear to make it up. I did spend part of an evening trying to figure out how to use a conversion lut, and didn’t quite get to an answer. This is going to feel like learning Emacs again…

It’s that “production grade color management pipeline” you mention that has me interested. I guess there’s no way around it. [stretches neck; cracks knuckles]

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Awesome with a side of never ending discovery?!

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:rofl:

I still use a Vim fork for most text tasks, so there!

(I could do almost all my necessary writing with a pencil, and it would last a while. Why do I constantly try to make life harder with a computer? Actually, I think you’re on to something.)

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using vim while rock climbing <3 now this thread seems to be going somewhere :slight_smile:

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Yeah, falling while screaming (…at Vim because I q: instead of :q again).

I now have a staged shot planned if I could find a rock wall. :slight_smile: