GPT Image 2 提示词怎么写：结构、示例和实测出图

Intended use: a poster for a community event, printed at A3.
Scene: a warm autumn evening in a small-town square, string lights overhead.
Subject: a vintage bicycle with a wicker basket full of apples, centered in the lower half.
Text (exact, render each line once):
Line 1, top, large bold serif: "HARVEST NIGHT MARKET"
Line 2, below it, smaller: "Saturday, November 8 · 5–10 pm"
Line 3, bottom, small caps: "Old Mill Square"
Style: screen-printed poster, three colours (deep red, mustard, cream), visible paper grain.
Constraints: no other text, no logos, no watermark.

Intended use: the hero image on an online shop's product page.
Scene: a seamless pale stone backdrop, soft morning window light from the left, a gentle shadow falling to the right.
Subject: a matte black stainless-steel water bottle with a bamboo cap, standing upright, slightly left of centre.
Details: small water droplets on the bottle, a sprig of fresh mint lying beside it, visible wood grain on the cap.
Photography: photorealistic product photo, 100mm macro lens look, sharp focus on the bottle, background softly out of focus.
Constraints: no text, no logo, no label on the bottle, no other objects.

Intended use: a one-page explainer for a coffee shop's blog.
Create a clean infographic titled "HOW POUR-OVER COFFEE WORKS".
Layout: four numbered steps in one vertical column; each step has a simple flat illustration on the left and a short label on the right.
Step labels (exact text):
1. "Grind 15 g of beans"
2. "Heat water to 94 °C"
3. "Bloom for 30 seconds"
4. "Pour slowly for 3 minutes"
Style: flat vector illustration, cream background, dark brown and teal accents, plenty of white space.
Constraints: no other text, no logos, every label spelled exactly as written.

Create a photorealistic candid portrait of a fictional woman in her fifties, a potter, sitting at her wheel in a small studio.
Framing: medium close-up at eye level, like a 35mm film photograph taken with a 50mm lens, shallow depth of field.
Details: real skin texture (pores, fine lines, freckles), grey hair tied back, a denim apron with clay stains, wet clay on her hands, shelves of unglazed bowls blurred behind her.
Lighting: soft daylight from a window on the left.
Constraints: no text, no watermark, natural colours, no heavy retouching.

Use the input image only as a style reference: copy its screen-printed look, its three-colour palette (deep red, mustard, cream) and its paper grain.
New subject: a lighthouse on a rocky headland at dusk, with a small sailboat on the sea below it.
Layout: the lighthouse centered, generous empty sky at the top.
Constraints: no text of any kind, no bicycle, no apples, no logos.

Change only the colour of the bottle, from matte black to matte sage green.
Keep everything else exactly the same: the bamboo cap, the mint sprig, the water droplets, the lighting, the shadow, the camera angle, the framing and the stone background.

Intended use: a test of exact object counts.
A top-down photo of a light wooden table with exactly seven red apples and exactly three green pears, arranged in one loose row, nothing else on the table.
Photography: photorealistic, soft even daylight, straight top-down view.
Constraints: exactly 7 apples and exactly 3 pears, no other fruit, no text.

Intended use: a design mockup for a pitch deck.
Create a realistic mobile app screen for a fictional plant-watering app called "Sprout", shown inside a plain modern phone frame on a light grey background.
Screen content (exact text):
Header: "Good morning, Maya"
Card 1: "Monstera — water today"
Card 2: "Fiddle-leaf fig — in 2 days"
Card 3: "Snake plant — in 6 days"
Bottom button: "Log watering"
Style: clean rounded cards, soft green accents, readable sans-serif text, generous spacing.
Constraints: no other text, no real brand logos, all text spelled exactly as written.

pip install requests
export OMNIAKEY_API_KEY="your-key"

import os
import time
import uuid

import requests

API = "https://api.omniakey.com/v1/media/tasks"
HEADERS = {"Authorization": f"Bearer {os.environ['OMNIAKEY_API_KEY']}"}

PROMPT = """Intended use: a one-page explainer for a coffee shop's blog.
Create a clean infographic titled "HOW POUR-OVER COFFEE WORKS".
Layout: four numbered steps in one vertical column; each step has a simple flat illustration on the left and a short label on the right.
Step labels (exact text):
1. "Grind 15 g of beans"
2. "Heat water to 94 °C"
3. "Bloom for 30 seconds"
4. "Pour slowly for 3 minutes"
Style: flat vector illustration, cream background, dark brown and teal accents, plenty of white space.
Constraints: no other text, no logos, every label spelled exactly as written."""

# 1. 建任务。只有重试同一个请求时才复用同一个 Idempotency-Key。
resp = requests.post(
    API,
    headers={**HEADERS, "Idempotency-Key": str(uuid.uuid4())},
    json={
        "model": "gpt-image-2",
        "type": "image",
        "operation": "generate",
        "input": {"prompt": PROMPT},
        "parameters": {"size": "1024x1536", "quality": "low"},
    },
    timeout=30,
)
resp.raise_for_status()
task = resp.json()
print("task:", task["id"], task["status"])

# 2. 轮询同一个任务直到完成。慢不等于失败，继续轮询这个 id。
while task["status"] in ("queued", "processing"):
    time.sleep(4)
    task = requests.get(f"{API}/{task['id']}", headers=HEADERS, timeout=30).json()

if task["status"] != "succeeded":
    raise SystemExit(f"task ended {task['status']}: {task.get('error')}")

# 3. 立刻下载，签名链接大约一小时后失效。
asset = task["assets"][0]
with open("pour-over.png", "wb") as f:
    f.write(requests.get(asset["url"], timeout=60).content)
print("saved pour-over.png", asset["mime_type"], asset["byte_size"], "bytes")

{
    "model": "gpt-image-2",
    "type": "image",
    "operation": "edit",
    "input": {
        "prompt": "Change only the colour of the bottle, from matte black to matte sage green. Keep everything else exactly the same.",
        "image": {"data": "<base64>", "mime_type": "image/jpeg"},
    },
    "parameters": {"size": "1536x1024", "quality": "medium"},
}