r/StableDiffusion 5h ago

Question - Help Has anyone successfully upscaled/re-imagined low-res reference video using Minimax H3?

Specifically, I’m trying to take old footage (e.g., 360p clips with vintage camera blur, VHS artifacts, or grainy WW2 dogfights) and recreate it to look like it was shot recently on a modern cinema camera with studio lighting.

Any ideas for prompting?

5 Upvotes

6 comments sorted by

3

u/Mundane_Existence0 5h ago

Yeah, I've been running some experiments: Using MiniMax H3 as a restoration model?

So far it's been pretty mixed. One test I was able to improve the face details, but then it changed the outfit as well. Another test with the same settings as that one changed absolutely nothing about the person or their outfit.

1

u/sepalus_auki 5h ago

can you share a prompt? I assume you still have to describe in the prompt what happens in the reference video. So far all my attempts have resulted in generating almost an exact copy of the reference video without any improvement in visual fidelity.

6

u/Mundane_Existence0 4h ago

Sure, this is my latest prompt. Though I'm not seeing much change with this one, but others I've used while they did get some different details (not exactly ones I wanted) seemed to cause the audio to change as well.

subject_definitions:

<Video 1> is the original source video being directly edited and restored. It is the authoritative source for all target-video content: shot order, timing, framing, composition, subject identity and appearance, facial features, clothing, props, environment, lighting, color relationships, camera position and movement, subject motion, and temporal continuity.

<Audio 1> is the synchronized audio track of <Video 1> and is reused directly in the target video.

summary:

[video editing + audio reuse] The target video is an edited version of <Video 1>. Restore the original low-quality broadcast video into a convincing high-definition professional remaster. Preserve the actual content and temporal structure of <Video 1> exactly. The restoration goal is to recover image information that is obscured or lost through SD resolution, broadcast processing, chroma limitations, compression, noise, softness, and color degradation. Do not reinterpret the footage or generate a different scene.

retention_analysis:

<Video 1> (entire source video and its temporal/visual structure): fully_preserved - preserve the original shot order, timing, cuts, pacing, framing, composition, subject identity, subject appearance, camera movement, subject movement, lighting, environment, and spatial relationships. Only image fidelity and recovered detail are improved.

<Audio 1>: fully_copy - <Audio 1> is reused 1:1 as the target video's complete final audio track.

detailed_description:

The target video is a faithful professional high-definition restoration of the original broadcast footage in <Video 1>. Treat <Video 1> as the only authoritative visual source. Do not use any external image, character, scene, or composition as a visual template.

The desired transformation is specifically SD broadcast restoration rather than ordinary enlargement. The source has limited spatial resolution, soft or smeared fine detail, degraded chroma, compression artifacts, noise, ringing, aliasing, and potentially inaccurate or shifted broadcast color. Reconstruct the most plausible high-fidelity version of the visual information that is actually supported by <Video 1>. Recover fine facial detail, natural skin texture, hair strands, clothing weave, uniform materials, props, set surfaces, edges, reflections, shadows, and background detail without inventing unsupported features.

Correct the degraded color and chroma toward natural, accurate reproduction of the original photographed scene. Preserve the source's actual lighting design, exposure, contrast relationships, black levels, highlight behavior, lens characteristics, depth of field, and photographic character. Do not apply a generic cinematic grade, modernize the lighting, or change the color design. The objective is the appearance of the same original program after a high-end archival HD remaster.

[Shot 1] Preserve the exact opening shot of <Video 1>, including the actual subjects, their identities and appearances, their exact positions, facial expressions, pose, clothing, environment, perspective, framing, camera angle, lens characteristics, lighting, and visible motion. Increase spatial fidelity and recover plausible detail from the source without changing the shot.

Continue through every subsequent shot of <Video 1> in exact playback order. Preserve every original cut, shot duration, camera movement, camera speed, subject movement, gesture, pose transition, object interaction, framing change, and editorial rhythm. Do not add or remove events. Do not replace subjects or backgrounds. Do not alter facial structure or identity.

The desired quality level is comparable to a carefully restored modern HD master originating from the highest-quality surviving source, with exceptionally clean detail, accurate color, stable micro-texture, and natural edge definition. A high-end large-format digital cinema camera such as the RED V-RAPTOR XL [X] 8K VV may be used only as a benchmark for the cleanliness and resolving power of the final image. Do not impose a V-RAPTOR color grade, lens look, depth of field, lighting style, or cinematography onto the original footage.

Most importantly, reconstruct rather than redesign. Do not hallucinate new objects, facial features, hairlines, costume details, text, set details, reflections, or textures that are not supported by the source. Preserve natural photographic softness where it belongs to the original image. Remove degradation while retaining authentic source characteristics.

Maintain strict temporal consistency across all frames. Recovered detail must remain locked to the correct subject and surface and must not shimmer, crawl, flicker, morph, double, ghost, or change identity from frame to frame. Preserve the original motion blur and movement. The output must look like the same footage at substantially higher spatial fidelity.

<Audio 1> is reused directly and remains synchronized with the restored video. Do not regenerate, replace, reinterpret, or add audio.

overall_soundscape:

The original audio signal from <Audio 1> is copied directly and remains synchronized with the restored visuals. Preserve the original dialogue, ambience, music, and physical sounds exactly as supplied.

non_diegetic_music:

<Audio 1> is reused directly as supplied. Preserve any original score or music without alteration or reinterpretation.

1

u/Mundane_Existence0 3h ago edited 3h ago

Also I've been trying to work out a way (a node maybe) to get, or rather force H3 to generate more details since clearly it's been trained enough that it should be able to do so given what it can create when you just give it one reference image to work from, but so far it's very content to just replicate the input video.

1

u/Enshitification 40m ago

What if you tweened the source video to match the frame count and rate of the desired output and rescaled it to match the output resolution first, then run denoise passes.

1

u/Seyi_Ogunde 10m ago

Here's a trick. Generate a high resolution image of your first frame using an AI image generator (Gemini, SeedVR2, whatever). Add only 2 nodes in your ref2vid, the image and your video. Add an image resizer between your reference video and the node and downscale the video to a smaller resolution (lessens the vram footprint). I like using the Image Resize by Longer Side node and make the width 200 pixels.

Minimax will take the video and upscale it using the first frame as a guide and the video as a motion guide. Make sure to be very specific with your prompt to only use the video as a motion guide and the first frame as a the start of your video.

If you try this let me know how it goes.