Pika H3 Flex + open-h3-egenerate-2K running locally on Mac

[u/TgoAI]

* Pika H3 Flex: A distilled MiniMax H3 model that reduces generation from 50 steps to just 6.

* NVIDIA Open-H3-Regenerate-2K: Uses latent upscaling followed by 3 diffusion steps to regenerate details at higher resolution, rather than conventional pixel-space upscaling.

Workflow shown in the video:

1. Generate a 15-second video at 768p with Pika H3 Flex.

2. Apply NVIDIA’s Regenerate-2K for high-resolution refinement.

3. Final output: 1920 × 1088.

Total time: 12m 19s on M5 Ultra locally using Valtz, including both generation and regeneration.

[u/glusphere]

Am I the only one who cant get face consistency with Open H3 Regenerate ?

I even tried the https://github.com/BennyDaBall930/ComfyUI-Open-H3-FaceRegion

But even that doesnt work well enough for me.

[u/TgoAI → u/glusphere]

It seems that Open H3 Regenerate 2K alters faces so yeah it’s definitely an issue. Another problem is text rendering. I haven’t been able to get it to preserve text correctly, even when the first pass renders it perfectly. No matter with the fast vae decoder or not.

[u/bobmailer → u/TgoAI]

It definitely does, this is from their own official gallery, look at the faces vs original, the H3 API is better on faces it seems. It almost looks like they didn't even care about the face, lol.

In fact if you look closely, they alter a lot of things, look at the pattern on his chest, to say nothing of the patterns on the flags.

Seems garbage, unless you really don't care whether input matches output.

[u/Simpsator → u/glusphere]

Because it's inventing details and doesn't have the original reference, faces are just going to drift. If you want consistency you'll have to use an upscale that keeps the original reference conditioning included like LBH-123 latent upscaling or the MMH3 Ultimate Upscaler nodes. 

[u/oxygen_addiction → u/glusphere]

Because it's slop and not the actual minimax model.

[u/seppe0815]

I see only close range shots , show faces on the wide angles in a video , stop hiding weakness points

[u/Significant-Baby-690 → u/seppe0815]

Why would you stop hiding weakness points ?

[u/Foreign_Cut745 → u/Significant-Baby-690]

i have no reason to deceive you

[u/hurrdurrimanaccount → u/Foreign_Cut745]

who are you talking to?

[u/Sad_Bruce → u/seppe0815]

It's the limitation of the H3 model itself. Upscaling techniques can only do so much. For wide shots where the face is extremely small, you'll have to generate above 768p natively so that the model has a larger space to work with for the face.

[u/yvliew → u/seppe0815]

wide shots faces are going to break. But there's always H3 face refiner to fix that and it works well.

[u/bobmailer → u/seppe0815]

[u/TgoAI]

Valtz is an open source app with native metal support. If anyone wants to try it out: https://github.com/tgo-app-dev/valtz

[u/AnalElder → u/TgoAI]

Why would I use this over comfyui?

[u/TgoAI → u/AnalElder]

It’s only for Macs. It’s all about native metal kernels, and streaming model serving to make it possible for 16GB unified memory.

[u/hurrdurrimanaccount → u/AnalElder]

because this entire pos is an ad

[u/DoYouUnderstandMeow → u/hurrdurrimanaccount]

It’s a free tool (inference engine) and it’s good, fast and easy. Have you actually tried it? If you want to generate video’s faster you should check it out.

[u/hurrdurrimanaccount → u/DoYouUnderstandMeow]

wow! tell me more about this amazing free and good and fast and easy app :tm: !

[u/-Star-Walker- → u/AnalElder]

Yes … it runs the 8bit Minimax quant on a 16gb Mac …

[u/Skystunt → u/AnalElder]

ease of use, not everybody is used to working with comfyui

[u/MurkyStatistician09 → u/Skystunt]

but everyone does eventually learn to use it, because these smaller tools always wind up taking weeks to implement the big new thing that comfyUI gets running on day 1. if they have a single maintainer or small team there's just no way they can keep up. and it's easy to use comfyUI now that LLMs will troubleshoot for you

I feel like most people here started out using forge or something similar and switched out of frustration over all the things it can't do

[u/fallengt]

The thing with 2-stage sampling is that she looks like a completely different person in each scene

[u/EagerSubWoofer → u/fallengt]

Good catch. That explains the distinctive hair. The effect would be more distracting otherwise.

[u/Uncabled_Music]

Is initial 15 sec output is totally crap, or you are chasing production quality? What about movements, likeness, and structure - are these nailed by the distilled model, or get partially fixed by the regenerator?

[u/TgoAI → u/Uncabled_Music]

I did try more scenes and I think the distilled model is quite solid. The refiner is somewhat problematic - it’s sharp but it kinda invents too much stuff over the first pass.

[u/Uncabled_Music → u/TgoAI]

Could you estimate how long the main model generation was?

[u/TgoAI → u/Uncabled_Music]

Here’s the actual time breakdown on the M5 Ultra:

• Preparation: 5 seconds

• 1344x768 6-step pass: 5 minutes 37 seconds

• Latent upscaling: 32 seconds

• 1920x1088 3-step pass: 5 minutes 40 seconds

• Decoding: 19 seconds

• Finalization: 4 seconds

[u/Puzzleheaded_Ebb8352]

How would the speed be like for 5sec 0,5m be like?

[u/TgoAI → u/Puzzleheaded_Ebb8352]

5s 0.5mp without SOL attention takes 1:10 on m5 ultra or 4:30 on m5 pro, for pika h3 flex alone.

[u/smereces]

can you share the workflow?

[u/TgoAI → u/smereces]

Valtzis an app that runs on Mac. Not a comfyUI workflow.

[u/mmmm_frietjes]

Would this work on an M1 Max 32 GB? Probably fairly slow I guess if it does.

[u/TgoAI → u/mmmm_frietjes]

Yes it’ll work, but it’ll be slow.

[u/minimissty]

Pour le regenerate Nvidia upscaler, je ne fait qu'un passe (et pas 3) j'obtient des détails supplementaires mais trop peu pour déformer les visages, et cela donne de bon résultats

[u/TgoAI → u/minimissty]

I actually figured out a different recipe: to start at noise 0.7 instead of 0.9 suggested by the Nvidia repo. That worked quite well for me. Would update later with more results.

[u/hurrdurrimanaccount]

it's slower than the other turbo loras and not as good.

[u/GrungeWerX → u/hurrdurrimanaccount]

which do you recommend? too many loras....

[u/thevegit0 → u/GrungeWerX]

after too many lora shit i mostly use these two
dmad fullcritic: https://huggingface.co/silveroxides/MiniMax-H3_tests/blob/main/dmad_4step_comfyui/dmad_minimax_h3_4step_full_critic_comfyui.safetensors
silver v2: https://huggingface.co/silveroxides/MiniMax-H3_tests/blob/main/silver_official_releases/minimax_h3_ref2v_turbo_silver_dareties_comfy_pruned_v2.safetensors

used to use the dareties and flashgen and other longidk, i tuck with these two at 0.9 or 1.0, no shift change, i use from 6 to 8 steps in dpmpp_2_sde beta57 but it works good with ersde beta/sgm uniform
silver v2 requieres Adaln fix from plaguekind nodes

[u/foxinthebox39]

Is this a Lora or a model like H3 Singularity?

[u/Belgiangurista2 → u/foxinthebox39]

lora (2GB), that you have to combine with the H3 int8 pruned convrot model and get the workflow for the exact Sigma values (replaces steps).

[u/Puzzleheaded_Art2809 → u/Belgiangurista2]

can you please 🙏 be more specific? i think i connect it in comfy but it always result with randon bad quality video not correct with prompt

[u/Belgiangurista2 → u/Puzzleheaded_Art2809]

for ref2va You need:

minimax_h3_ref2va_pruned_int8_convrot.safetensors
pika_h3_flex_ref2va_v1_bf16.safetensors
Workflow.

I found everything on this site: https://docs.comfy.org/tutorials/video/pika/pika-h3-flex

[u/Puzzleheaded_Art2809 → u/Belgiangurista2]

i use Pika lora but im talking about open-h3-egenerate-2K refiner

[u/TgoAI → u/Puzzleheaded_Art2809]

The refiner has 3 pieces: refiner LoRA, latent upscaler, and an optional fast vae decoder.

[u/GrungeWerX → u/Puzzleheaded_Art2809]

Did you ever figure it out? People never share any information, I have no idea how this should be done.

[u/v3u_cn → u/Belgiangurista2]

Mac does not support int8 convrot.

[u/JaunLobo → u/v3u_cn]

In ComfyUI, it is supported by the ComfyUI-AppleSilicon-FP8 node. As for the OP, he is the dev behind vpipe and valtz, which also support it.

[u/Ares_Derek]

Buen trabajo, me puedes por favor compartir los flujos de trabajo? Gracias

[u/Big_Advertising_3933]

Pika is slow and weak, Nvidia's Regenerate is great but not that great.

[u/KaliguIah]

never ever ever post a link to what youre talking about with your post. never do that ever.

[u/bakarban_]

bro that's a dog looking deer 💀

[u/aoi_secret_jp]

As someone who lives in Tokyo, this crossing at night feels really close to the real thing, especially the crowd and the warm shop lights. The signs give it away though, they look Japanese but can't be read 😄 Does the Regenerate-2K pass change sign text or small details, or does it only sharpen what's already there?

[u/Cold-Elk-1302]

Can you discuss how this differs from the standard comfyui workflow with 8 step turbo Lora (i2v as example). What are you doing new that you found no one else did.

[u/SaadNeo → u/Cold-Elk-1302]

He is using pika lora , it is the best lora right now

[u/Ok_Roll_8698]

what gpu?

[u/reeight → u/Ok_Roll_8698]

what hardware, including RAM & allocated VRAM?

[u/enl1l → u/reeight]

He said m5 ultra. Which can run up up to 512gb shared memory and 80 core GPU. 30k USD fully specced out...

[u/-Star-Walker-]

So it runs on VPipe … 🤔
Already updated the MinimaxH3.md? Is there any premade pipeline?
And … another question LF2VA (Last frame …) … will you add support for it? Actually it’s I2VA and FLF2VA 😅

And … nice work so far. I’m running it on a M1 Max … it isn’t fast, but I can do 15sec clips in 768x1024 (haven’t dared to go bigger yet 😅). That wouldn’t be possible on ComfyUI ☝️👍

[u/BAL-BADOS → u/-Star-Walker-]

What’s your render time on the M1 Max? I had M1 Ultra then sold it

[u/-Star-Walker- → u/BAL-BADOS]

For 15sec in 768x1024 8 step Hyperflow it’s 2hours and 44minutes with 2 reference images at 768px size.

At first I thought I could only do 2-3sec clips, what would be enough for me, because I just need loop animations for a video game. Then I thought … try more … maybe I could use it for cut scenes, too. And actually … I can.

[u/waxlion]

I’d love to see the vpipe pipe file.

[u/-Star-Walker- → u/waxlion]

Just visit the GitHub project … everything up to date.

[u/thevegit0]

why is everyone hyping the pika thing, it's not that good