Model note
2026-08
v2 in production · internal eval
Alpha-native super-resolution for flat artwork
Print artwork is not a photograph: our upscaler reconstructs the alpha channel, the cut line of the print, natively, where general-purpose super-resolution returns flat RGB and the silhouette is merely stretched.
Off-the-shelf super-resolution models are trained on photographs. On flat artwork they hallucinate glyph texture (an e becomes an o), wash discrete design colours toward means, and ignore transparency entirely. On a DTF transfer the alpha edge is the physical cut. Generic tools optimise how an image looks on a screen; prepress needs what survives on fabric.
Method
The model is trained exclusively on flat artwork with a print-realistic damage model (compression artefacts, resampling loss, colour bleed) on pairs where the original is known. It learns to reverse damage rather than to invent detail.
It is deliberately non-generative: no adversarial objective, because plausible-looking text is exactly how wrong text gets invented. It runs on commodity CPU.
Evaluation
Internal production designs with held-out ground truth. We measure what print cares about: edge sharpness relative to the true original, silhouette fidelity (shape IoU), palette drift against the design's own colours, and stroke survival, instead of PSNR/LPIPS, which reward photographic plausibility rather than print fidelity.
Results (internal evaluation)
- Damaged reference logo, edge sharpness vs true original
- 83% → 98%
- Held-out designs restored to print bar without external vendor (n=20)
- 20/20
- Vendor-escalation rate on the free tier (same eval)
- 45% → 0%
- Ink mass preserved vs true original
- ±1%
Baseline: against classical resampling (Lanczos) the same reference measures 24% of true sharpness.
Known limits
- Detail that no longer exists in the source cannot be honestly recovered: a sub-pixel dot on an i stays lost rather than invented.
- Extremely low-resolution sources below roughly a quarter of print resolution are refused rather than faked.
- Fine connected script remains the hardest class; the system flags it instead of hiding it.
