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How to Slim a Face in a Photo Without Smearing Hair or Skin Texture

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A real source portrait beside a real subtle Seedream 4.5 contour edit

A face-slimming edit is easy to overfit. A model can produce a narrower thumbnail by erasing cheek texture, bending hair into the jaw, shrinking the mouth, or changing the person entirely. The right target is a bounded contour adjustment whose surrounding pixels still make sense.

This tutorial uses the current Voor Face Slimming AI workspace and its real public before/after example. It does not submit a new generation.

Treat the jaw as a region, not a new identity

Start with an authorized, front-facing portrait where the jaw, ears, hairline, neck, and background are visible. Avoid beauty filters, motion blur, or a hand covering the cheek; those remove the very evidence needed to detect warping.

Define a protected ring around the requested edit:

const contourContract = {
  editable: ['lower-cheek contour', 'jaw outline'],
  locked: [
    'eyes', 'nose', 'mouth', 'ears', 'age', 'skin tone',
    'pores', 'hair strands', 'neck width', 'shoulders',
    'camera', 'background lines', 'light direction'
  ],
  rejectIf: ['identity drift', 'plastic skin', 'hair smear', 'bent background']
};
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The ring is crucial. If pixels immediately outside the jaw move, the edit is changing more than contour.

Inspect today's generator state

The route currently uses Seedream 4.5. It exposes subtle, stronger, and lens-oriented presets, plus a required Prompt and Image input. Current settings include Match Input Image aspect ratio, 2K or 4K size, Max Images (1 by default), Sequential Image Generation (Disabled by default), Public, Reset, and Generate.

For one image with sequential generation disabled, the current database pricing rule estimates 14 credits. Resolution does not change that stored one-image estimate today, while asking for more outputs does. Always read the live signed-in estimate before Generate.

Public output is not a harmless default for a face. Make sure both edit permission and distribution permission are explicit before upload.

Prompt with a numeric ceiling

Choose the subtle option first and keep the brief narrow:

Make a subtle natural contour adjustment, approximately 10% narrower at the lower cheeks and jaw only. Preserve the same person, age, eyes, nose, mouth, ears, skin tone, pores, hair strands, neck width, shoulders, crop, background, and lighting. Do not smooth skin, sharpen the chin, enlarge the eyes, or apply makeup.

“Approximately 10%” is a ceiling, not a measurement guarantee. It tells the model this is a small adjustment. Avoid subjective bundles such as “make me prettier, younger, slimmer, and glamorous,” because they authorize unrelated changes.

Keep Match Input Image. Changing the crop at the same time makes a before/after comparison less trustworthy.

Build a five-zone diff

The real baseline, contour result, and a matched texture-check crop

Review the result at 100%, then zoom into five zones:

  1. Jaw edge: the contour moves smoothly without a hard cut or doubled outline.
  2. Hair/cheek boundary: individual strands continue across the edited region instead of melting into skin.
  3. Skin texture: pores and small tonal variations remain comparable on both cheeks.
  4. Ear/neck transition: ears do not move and the neck is not narrowed to support the illusion.
  5. Background adjacency: window frames, walls, or fabric near the face remain straight.

A lightweight manual score can prevent “looks okay” approval:

function reviewFaceSlim(result) {
  const required = [
    result.identitySame,
    result.texturePreserved,
    result.hairBoundaryClean,
    result.earsAndNeckStable,
    result.backgroundStraight
  ];
  return required.every(Boolean) && result.contourChange <= 'subtle';
}
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Do not use automated face scores as consent or truth. The function represents a human inspection gate.

Diagnose before retrying

If skin becomes waxy, repeat the pore/texture lock and remove beauty language. If hair smears, reduce the contour change and name the exact hair boundary. If the mouth or nose moves, restate the identity lock and ask for lower-cheek/jaw only. If background lines bend, keep the source ratio and specify a fixed camera/background.

If a 10% edit passes but feels too weak, do not jump to a dramatic preset. Increase one step, compare again, and keep the same protected ring.

The deliverable is not “a thinner face.” It is an honest styling preview where the person and photographic evidence remain recognizable. Open the exact Face Slimming workspace, start subtle, and approve texture before contour strength.

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