如何生成可复用的透明背景设计素材

import base64
import os
from pathlib import Path

from openai import OpenAI
from PIL import Image

if not os.getenv("OPENAI_API_KEY"):
    raise RuntimeError("Set OPENAI_API_KEY before running this notebook.")

IMAGE_MODEL = "gpt-image-2.5-flare"

client = OpenAI()
asset_dir = Path("images/transparent-image-assets")
asset_dir.mkdir(parents=True, exist_ok=True)

# 共享品牌风格与真透明约束后缀：统一琥珀玻璃材质、拉丝黄铜配件、暖光棚拍质感，
# 并明确要求输出完整可见的孤立物体、保留自然折射与半透明层次，禁止任何背景、底座、投射阴影、文字与水印
brand_prompt = (
    "One object from STILLROOM, an understated luxury botanical home-fragrance "
    "atelier: artisanal warm amber and honey-tinted hand-blown glass, subtle "
    "brushed brass hardware, natural ivory cotton cord, quiet "
    "Japanese-Scandinavian restraint, warm side-lit editorial studio "
    "photography, photorealistic micro-detail, immaculate premium campaign "
    "quality. Full object completely visible and generously padded. Preserve "
    "every natural transparency, refraction, translucent layer and fine "
    "material edge. Output an isolated object on actual fully transparent "
    "alpha; no backdrop, no rectangle, no plinth, no cast shadow, no readable "
    "writing, no label text, no watermark."
)

# 四款香氛单品的独立外观描述：香水瓶（配薄纱丝带）、草本精华油（内含悬浮茴香枝）、藤条香薰（配纤细芦苇与羽毛状蒲苇）、磨砂玻璃蜡烛（配细棉绳与尤加利叶）
products = {
    "amber-parfum": (
        "A sculptural substantial clear honey-amber faceted glass "
        "eau-de-parfum bottle, slender rectangular body with softly rounded "
        "shoulders, heavy clear crystal cap, a small delicate sheer ivory "
        "organza ribbon loosely tied around the brushed brass neck with one "
        "translucent airy tail floating naturally; visible golden fragrance "
        "liquid and beautifully realistic glass refraction."
    ),
    "botanical-oil": (
        "A slim elegant cylindrical deep honey-amber transparent hand-blown "
        "glass botanical body-oil bottle, tall slender polished brushed-brass "
        "dropper cap with tiny ivory rubber bulb, translucent pale golden "
        "botanical oil inside and a tiny delicate preserved sprig of green "
        "wild fennel visible suspended within the liquid; subtle refraction, "
        "premium apothecary design."
    ),
    "reed-diffuser": (
        "A rounded low smoked-amber translucent glass home-fragrance diffuser "
        "vessel containing warm golden scented oil, topped by five naturally "
        "splayed very thin blonde rattan reeds and one extraordinarily "
        "delicate feathery dried pampas grass stem with fine hairlike wisps "
        "extending outward; realistic transparent glass and botanical fibers."
    ),
    "garden-candle": (
        "A quiet luxurious handmade botanical candle in a thick heavy "
        "translucent smoky-amber and milky frosted glass tumbler, creamy "
        "natural ivory wax, one small gently glowing clean candle flame, "
        "delicate transparent-edged frosted glass rim, a loose fine ivory "
        "cotton cord tied around the vessel with one tiny dried eucalyptus "
        "sprig, perfect warm reflections."
    ),
}

generate_images = True

if generate_images:
    for filename, product_prompt in products.items():
        result = client.images.generate(
            model=IMAGE_MODEL,
            prompt=f"{product_prompt} {brand_prompt}",
            background="transparent",
            size="1024x1536",
            quality="high",
            output_format="png",
        )

        image_bytes = base64.b64decode(result.data[0].b64_json)
        (asset_dir / f"{filename}.png").write_bytes(image_bytes)

for filename in products:
    with Image.open(asset_dir / f"{filename}.png") as image:
        if image.mode != "RGBA":
            raise ValueError(f"{filename}.png does not have an alpha channel.")

        transparent_pixels = image.getchannel("A").histogram()[0]
        total_pixels = image.width * image.height
        transparent_percentage = 100 * transparent_pixels / total_pixels

        print(
            f"{filename}.png: {image.width}x{image.height}, "
            f"{transparent_percentage:.2f}% fully transparent"
        )

codex_prompt = '''
Build a simple, responsive single-page campaign website for STILLROOM, a
premium botanical home-fragrance brand, using these existing transparent PNGs:

- images/transparent-image-assets/amber-parfum.png
- images/transparent-image-assets/botanical-oil.png
- images/transparent-image-assets/reed-diffuser.png
- images/transparent-image-assets/garden-candle.png

Show the heading "One collection, four seasons." Add Spring, Summer, Autumn,
and Winter controls that change the campaign background and seasonal copy.
Include controls for one product, two products, and the full collection.
Let visitors choose the featured product and rearrange the same transparent
PNGs over every background. Add a "Show transparency" checkerboard toggle.
Keep the page visually clean and centered on the products. Do not generate
replacement images or run a separate background-removal step.
'''.strip()

print(codex_prompt)

quarterly_revenue = {
    "Q1": 42,
    "Q2": 51,
    "Q3": 63,
    "Q4": 78,
}

regional_pipeline = {
    "North America": 46,
    "Europe": 29,
    "APAC": 25,
}

revenue_growth = (
    (quarterly_revenue["Q4"] - quarterly_revenue["Q1"])
    / quarterly_revenue["Q1"]
)

print(f"Quarterly revenue: {quarterly_revenue} USD millions")
print(f"Regional pipeline: {regional_pipeline} percent")
print(f"Q1-to-Q4 revenue growth: {revenue_growth:.0%}")

revenue_values = ", ".join(
    f"{quarter} = ${amount}M"
    for quarter, amount in quarterly_revenue.items()
)

pipeline_values = ", ".join(
    f"{region} = {percentage}%"
    for region, percentage in regional_pipeline.items()
)

chart_prompts = {
    "quarterly-revenue-growth": (
        "Create one polished enterprise bar chart on a genuinely "
        "transparent background for a dark navy PowerPoint slide. "
        f"Use exactly four ascending bars with these values: {revenue_values}. "
        "Use cobalt blue, bright blue, electric azure, and turquoise bars. "
        "Add white quarter labels below each bar and white dollar-value "
        "labels above each bar. Add a subtle turquoise upward-trend arrow. "
        "Keep the plot area, grid, and space between bars transparent. "
        "Do not add a background, filled panel, frame, title, or card."
    ),
    "regional-pipeline-mix": (
        "Create one polished enterprise doughnut chart on a genuinely "
        "transparent background for a dark navy PowerPoint slide. "
        f"Use exactly these regional pipeline shares: {pipeline_values}. "
        "Use turquoise, cobalt blue, and coral segments, with a white "
        "100% label in the center. Place a white-text regional legend "
        "beside the chart. Keep the doughnut center, legend area, and "
        "all surrounding space transparent. Do not add a background, "
        "filled panel, frame, title, or card."
    ),
}

generate_charts = True

if generate_charts:
    for filename, prompt in chart_prompts.items():
        result = client.images.generate(
            model=IMAGE_MODEL,
            prompt=prompt,
            background="transparent",
            size="1536x1024",
            quality="high",
            output_format="png",
        )

        image_bytes = base64.b64decode(result.data[0].b64_json)
        (asset_dir / f"{filename}.png").write_bytes(image_bytes)

for filename in chart_prompts:
    with Image.open(asset_dir / f"{filename}.png") as image:
        if image.mode != "RGBA":
            raise ValueError(f"{filename}.png does not have an alpha channel.")

        transparent_pixels = image.getchannel("A").histogram()[0]
        total_pixels = image.width * image.height
        transparent_percentage = 100 * transparent_pixels / total_pixels

        if transparent_pixels == 0:
            raise ValueError(f"{filename}.png has no fully transparent pixels.")

        print(
            f"{filename}.png: {image.width}x{image.height}, "
            f"{transparent_percentage:.2f}% fully transparent"
        )

presentation_prompt = f"""
Create one editable 16:9 PowerPoint slide for a fictional NORTHSTAR CLOUD
FY26 Q4 board review using these existing transparent PNG charts:

- images/transparent-image-assets/quarterly-revenue-growth.png
- images/transparent-image-assets/regional-pipeline-mix.png

Mock quarterly revenue, in USD millions: {quarterly_revenue}
Mock regional pipeline mix, in percent: {regional_pipeline}
Q1-to-Q4 revenue growth: {revenue_growth:.0%}

Use a subtle dark navy-to-teal gradient as the slide's native background.
Add the headline "Growth is accelerating across every region."
Add the subheadline "Revenue climbed 86% over four quarters while pipeline
stayed globally diversified."

Place the quarterly revenue chart on the left and the regional pipeline chart
on the right. Add a heading and short data description above each chart.
Preserve each PNG's real alpha channel so the gradient remains visible behind
both charts. Do not add white image frames, background panels, decorative
shapes, or a separate background-removal step.

Keep the slide clear, polished, and consistent with an enterprise board-deck
template. Add the fictional company name, reporting period, confidentiality
notice, and page number as editable PowerPoint text.
""".strip()

print(presentation_prompt)

design_prompts = {
    "design-app-icon": (
        "Create one premium rounded-square app icon with an abstract "
        "folded paper bird in cobalt blue, lavender, and peach. Keep "
        "everything outside the rounded icon tile transparent. No text, "
        "watermark, shadows, or background."
    ),
    "design-sticker": (
        "Create one illustrated strawberry character sticker with rich "
        "coral-red fruit, sage-green leaves, and a close-fitting cream "
        "die-cut border. Keep everything outside the sticker border "
        "transparent. No text, watermark, shadows, or background."
    ),
    "design-decoration": (
        "Create one delicate editorial botanical sprig with fine "
        "dark-sage branches, muted green leaves, and small coral berries. "
        "Keep all space around and between the thin branches and leaves "
        "transparent. No text, shadows, or background."
    ),
}

generate_design_assets = True

if generate_design_assets:
    for filename, prompt in design_prompts.items():
        result = client.images.generate(
            model=IMAGE_MODEL,
            prompt=prompt,
            background="transparent",
            size="1024x1024",
            quality="high",
            output_format="png",
        )

        image_bytes = base64.b64decode(result.data[0].b64_json)
        (asset_dir / f"{filename}.png").write_bytes(image_bytes)

merchandise_prompts = {
    "merchandise-design": (
        "Create one premium outdoors-inspired apparel illustration with "
        "an amber setting sun, slate-blue mountains, evergreen pine trees, "
        "a pale turquoise river, and small coral wildflowers. Arrange the "
        "elements into an organic compact circular composition with subtle "
        "screen-print texture. Keep the surrounding area and open spaces "
        "between the graphic elements transparent. No text, bounding "
        "badge, white rectangle, garment, or background."
    ),
    "merchandise-blank-tshirt": (
        "Create one photorealistic premium unisex ivory crew-neck T-shirt "
        "shown completely flat, front-facing, and centered. Leave the "
        "chest completely blank for a print design and keep everything "
        "outside the garment silhouette transparent. No person, hanger, "
        "mannequin, logos, graphics, shadows, or background."
    ),
    "merchandise-blank-sweatshirt": (
        "Create one photorealistic premium forest-green crew-neck "
        "sweatshirt shown completely flat, front-facing, and centered. "
        "Leave the chest completely blank for a print design and keep "
        "everything outside the garment silhouette transparent. No "
        "person, hanger, mannequin, logos, graphics, shadows, or background."
    ),
}

generate_merchandise_assets = True

if generate_merchandise_assets:
    for filename, prompt in merchandise_prompts.items():
        result = client.images.generate(
            model=IMAGE_MODEL,
            prompt=prompt,
            background="transparent",
            size="1024x1024",
            quality="high",
            output_format="png",
        )

        image_bytes = base64.b64decode(result.data[0].b64_json)
        (asset_dir / f"{filename}.png").write_bytes(image_bytes)

from PIL import ImageDraw, ImageFont


def visible_region(image):
    # 自动裁除四周完全透明的留白边距，不改变任何可见像素
    bounds = image.getchannel("A").getbbox()
    if bounds is None:
        raise ValueError("Expected a transparent PNG with visible artwork.")
    return image.crop(bounds)


canvas = Image.new("RGBA", (1600, 1020), "#f7f5f0")
draw = ImageDraw.Draw(canvas)

heading_font = ImageFont.load_default(size=57)
body_font = ImageFont.load_default(size=21)
label_font = ImageFont.load_default(size=25)
small_font = ImageFont.load_default(size=17)

draw.text((86, 70), "One design, ready to wear.", font=heading_font, fill="#202a27")
draw.text(
    (89, 151),
    "One transparent artwork. Two products. No background removal.",
    font=body_font,
    fill="#68726d",
)

with Image.open(asset_dir / "merchandise-design.png") as image:
    print_design = visible_region(image.convert("RGBA"))

garments = [
    ("merchandise-blank-tshirt", "Everyday T-shirt", "Natural cotton"),
    ("merchandise-blank-sweatshirt", "Essential sweatshirt", "Forest green"),
]

for index, (filename, title, color) in enumerate(garments):
    card_x = 86 + index * 741
    card_y = 221
    card_width = 690
    card_height = 691

    draw.rounded_rectangle(
        (card_x, card_y, card_x + card_width, card_y + card_height),
        radius=28,
        fill="#ffffff",
    )

    with Image.open(asset_dir / f"{filename}.png") as image:
        garment = visible_region(image.convert("RGBA"))

    garment.thumbnail((610, 505), Image.Resampling.LANCZOS)
    garment_x = card_x + (card_width - garment.width) // 2
    garment_y = card_y + 55 + (505 - garment.height) // 2

    artwork = print_design.copy()
    artwork.thumbnail(
        (round(garment.width * 0.32), round(garment.height * 0.32)),
        Image.Resampling.LANCZOS,
    )

    chest_x = (garment.width - artwork.width) // 2
    chest_y = round(garment.height * 0.28)
    garment.alpha_composite(artwork, dest=(chest_x, chest_y))
    canvas.alpha_composite(garment, dest=(garment_x, garment_y))

    draw.text((card_x + 41, card_y + 578), title, font=label_font, fill="#202a27")
    draw.text((card_x + 41, card_y + 620), color, font=small_font, fill="#68726d")

output_path = asset_dir / "merchandise-print-mockups.png"
canvas.convert("RGB").save(output_path, optimize=True)
print(f"Saved merchandise preview to {output_path}")