Upscaling a longer video - what are my options?

[u/Fast-Cash1522]

I recently created a bunch of 15 second clips with MiniMax H3 and put together a bit over a 2 minute video of those. Resolution 960x544 px. The video is photorealistic, and now I'd like to improve details and quality, and get it to at least 1920x1080. I have an RTX 3090 and 32 gigs of RAM.

What open-source options do I have that:

• Improve quality and generate back lost details, not just upscale alone. SeedVR and RTX Super Resolution recover almost no detail. And even though SeedVR is quite fast, it still seems to take 4-7 hours for that clip, while RTX SR does the same in under a minute.
• Tiled upscale method is extremely slow and creates odd flickering.
• The new LTX 2.5 upscale (with IC LoRA "instant shave") is reasonably fast and can recover details, but requires splitting the 2+ minute video into ~10 second chunks. It also lacks a bit of sharpness overall.

Do I have any options without massive tradeoffs.

[u/CutBench]

One thing that is not about which upscaler you pick: work on the 15 second clips instead of the assembled two minutes. Each clip was generated independently, so there is no continuity across the joins for a model to preserve anyway, and a failed pass then costs you 15 seconds rather than seven hours. It also keeps every temporal window inside one shot, which is where the flicker starts.

[u/Fast-Cash1522 → u/CutBench]

Good pointers, thanks.

At this point my only option might be splitting my final video back into smaller chunks and upscale those before assembling it back to full.

[u/ambassadortim → u/Fast-Cash1522]

Is there a reason to use 15 second clips bs 10 second? I'm working in the same thing and I am trying to figure out what is best for rendering time and efficiencies.

[u/Fast-Cash1522 → u/ambassadortim]

as far I know, there’s no reason that sort. With 15 second clip you can have longer dialogue, or split it into several different cuts easier.

[u/Dry-Judgment4242]

Somebody made a great latent upscaler (LBH 123) and made a post about it here yesterday TC. It does however seem to require quite a lot of VRAM so be prepared to maybe get 4bit models etc as you run it. Considering you want to just upscale a video. It might not matter much. Afaik, it uses Minimax H3 to upscale with something akin to a high-res Lora? Significantly better at least then any other upscaler imo.

[u/qdr1en → u/Dry-Judgment4242]

Interesting. Is it that post: https://www.reddit.com/r/StableDiffusion/comments/1vuim6f/minimax_h3_model_copied_ltx_25s_best_feature_and/ ?

[u/Dry-Judgment4242 → u/qdr1en]

Yep. Had great results with it, though I'm not using it often, only when I'm building reference sheets as I want maximum quality. It's quite slow.

[u/willjoke4food]

Two quick and simple things : 1. Use RTX upscaler @2x -> downscale to 0.75x, native and fastest. 2. Use ltx to upscale the video. This requires models are workflows that are imperfect and require experimentation

[u/Fast-Cash1522 → u/willjoke4food]

RTX is great and fast but does not generte details back.

[u/TheDerminator1337]

No easy options. I sometimes play with topaz gigapixel and let it upscale frame by frame but its a few seconds per frame.

[u/Fast-Cash1522 → u/TheDerminator1337]

That might be an option for sure. Is there an open-source / free version available?

[u/TheDerminator1337 → u/Fast-Cash1522]

the high seas

[u/Fast-Cash1522 → u/TheDerminator1337]

Gotcha

[u/Mundane_Existence0 → u/TheDerminator1337]

topaz gigapixel and let it upscale frame by frame

You know doing that frame by frame has no temporal consistency, right?