The safest AI sign edit changes one quoted string and treats every other pixel as protected. Define the old text, new text, exact region, typography constraints, and a keep-list before generation; then compare the untouched area instead of judging only the new letters.
The current Voor Képszerkesztő AI editor selects GPT Image 2. Its Hungarian UI exposes a required image and prompt, presets including Felirat for text, size ratios, Advanced Settings, Public · watermarked visibility, and Generate. The inspected quote is 56 credits. Generate was not submitted.
Specify a one-region patch
Use quotes for the text contract:
Replace only “8–18” with “7–20” on the cafe chalkboard.
Keep “NYITVA”, the same chalk weight, spacing, baseline, perspective, board grain,
cafe interior, reflections, lighting, crop, and every non-target character unchanged.
Short text is easier to validate. If the phrase is long, angled, or business-critical, generate the clean image and typeset the final copy deterministically instead.
Build an untargeted-region mask
The new glyphs are allowed to change. The rest of the frame is not. This minimal Python sketch creates a protected-region score when you supply a mask whose white pixels represent the edited text box:
from PIL import Image, ImageChops
import numpy as np
before = np.asarray(Image.open("before.png").convert("RGB"), dtype=np.int16)
after = np.asarray(Image.open("after.png").convert("RGB"), dtype=np.int16)
edit_mask = np.asarray(Image.open("text-mask.png").convert("L")) > 127
delta = np.abs(after - before).mean(axis=2)
protected_delta = delta[~edit_mask]
print({
"protected_mean": float(protected_delta.mean()),
"protected_p95": float(np.percentile(protected_delta, 95)),
})
Compression and antialiasing mean the target is not literal zero. Compare against a threshold chosen for the file format and inspect every high-delta cluster.
Review type and scene separately
For type, check spelling, numerals, baseline, weight, perspective, and contrast. For the scene, inspect the board edge, reflections, shadows, nearby objects, light direction, and crop. A convincing “7–20” still fails if the model repaints the cafe.
Do not use generated text for safety signs, legal notices, prices, medication, or evidence without independent verification. Use only images you have the right to edit. Public-watermarked processing is inappropriate for confidential signage or private locations.
The release gate is one correct replacement plus a measured untouched region. Open the same image editor with that patch contract.
