商品写真APIで1枚からストア対応画像を量産する

{
  "product": "250 ml skincare bottle",
  "must_keep": [
    "exactly one bottle",
    "tall rounded-rectangle silhouette",
    "short matte-white pump",
    "cobalt band at the lower quarter",
    "warm-white body with a satin finish",
    "front label position and all existing marks",
    "height-to-width ratio"
  ],
  "may_change": [
    "background",
    "surface",
    "lighting direction",
    "contact shadow",
    "crop room"
  ],
  "must_not_create": [
    "new words or logos",
    "price or discount badge",
    "ingredients or certification claim",
    "extra bottle, cap, pump, or packaging"
  ]
}

Use Image 1 as the exact product identity.

Keep exactly one product. Preserve its silhouette, dimensions, pump position,
warm-white satin material, cobalt color boundary, surface texture, and every
existing label mark. Do not redesign, relabel, remove, or add branding.

Change only the setting: place the product centered on a warm-white seamless
studio sweep. Use a large soft key light from the upper left, even front detail,
and a natural contact shadow directly below the bottle. Keep the whole product
visible with at least 10% crop room on every side.

No hands, people, props, boxes, extra products, added text, badges, dramatic
reflections, clipped edges, or floating object.

curl https://reapi.ai/api/v1/images/generations \
  -H "Authorization: Bearer $REAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "nano-banana-2-lite",
    "prompt": "Use Image 1 as the exact product identity. Keep exactly one product. Preserve its silhouette, dimensions, pump position, material, color boundaries, surface texture, and every existing label mark. Do not redesign, relabel, remove, or add branding. Change only the setting: center it on a warm-white seamless studio sweep with a soft key light from upper left and a natural contact shadow. Keep the whole product visible with at least 10% crop room. No hands, people, props, extra products, added text, badges, clipped edges, or floating object.",
    "image_urls": ["https://assets.example.com/my-product.jpg"],
    "aspect_ratio": "1:1"
  }'

TASK_ID="task_replace_me"

curl "https://reapi.ai/api/v1/tasks/$TASK_ID" \
  -H "Authorization: Bearer $REAPI_API_KEY"

import { writeFile } from 'node:fs/promises';

const apiKey = process.env.REAPI_API_KEY;
const sourceUrl = process.env.SOURCE_IMAGE_URL;
const model = process.env.IMAGE_MODEL || 'nano-banana-2-lite';

if (!apiKey || !sourceUrl) {
  throw new Error('Set REAPI_API_KEY and SOURCE_IMAGE_URL first.');
}

const prompt = `Use Image 1 as the exact product identity.
Keep exactly one product. Preserve its silhouette, proportions, hardware,
material, color boundaries, surface texture, and every existing label mark.
Do not redesign, relabel, remove, or add branding.
Change only the setting: center it on a warm-white seamless studio sweep with
a soft key light from upper left and a natural contact shadow. Keep the whole
product visible with at least 10% crop room. No hands, people, props, added
text, badges, extra products, clipped edges, or floating object.`;

function requestBody(selectedModel) {
  const common = {
    model: selectedModel,
    prompt,
    image_urls: [sourceUrl],
  };

  if (selectedModel === 'nano-banana-2-lite') {
    return { ...common, aspect_ratio: '1:1' };
  }
  if (selectedModel === 'gpt-image-2') {
    return { ...common, size: '1:1', resolution: '1k' };
  }
  if (selectedModel === 'doubao-seedream-5-0-pro') {
    return { ...common, aspect_ratio: '1:1', quality: 'basic' };
  }
  if (selectedModel === 'gemini-3-pro-image-preview') {
    return { ...common, size: '1:1', resolution: '1k' };
  }
  throw new Error(`Unsupported IMAGE_MODEL: ${selectedModel}`);
}

const headers = {
  Authorization: `Bearer ${apiKey}`,
  'Content-Type': 'application/json',
};

async function readJson(response) {
  const body = await response.json();
  if (!response.ok) {
    const message = body.error?.message || JSON.stringify(body);
    throw new Error(`HTTP ${response.status}: ${message}`);
  }
  return body;
}

const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

async function getTask(taskId) {
  for (let attempt = 0; attempt < 4; attempt += 1) {
    let response;
    try {
      response = await fetch(`https://reapi.ai/api/v1/tasks/${taskId}`, {
        headers: { Authorization: `Bearer ${apiKey}` },
        signal: AbortSignal.timeout(15_000),
      });
    } catch (error) {
      if (attempt === 3) throw error;
      await sleep(1000 * 2 ** attempt);
      continue;
    }

    if (response.status === 429) {
      const seconds = Number(response.headers.get('retry-after'));
      await response.body?.cancel();
      await sleep(Number.isFinite(seconds) ? seconds * 1000 : 5000);
      continue;
    }

    if ([502, 503, 504].includes(response.status)) {
      await response.body?.cancel();
      await sleep(1000 * 2 ** attempt);
      continue;
    }

    return readJson(response);
  }

  throw new Error(`Task ${taskId} could not be read after transient errors`);
}

// Submit once. If this connection fails ambiguously, reconcile before
// re-running the script: the server may already have accepted the task.
const submission = await readJson(
  await fetch('https://reapi.ai/api/v1/images/generations', {
    method: 'POST',
    headers,
    body: JSON.stringify(requestBody(model)),
    signal: AbortSignal.timeout(30_000),
  }),
);

console.log(`submitted ${submission.id}`);

const deadline = Date.now() + 5 * 60 * 1000;
let task;

while (Date.now() < deadline) {
  await sleep(3000);
  task = await getTask(submission.id);
  if (task.status === 'completed' || task.status === 'failed') break;
}

if (!task || task.status === 'processing') {
  throw new Error(
    `Local polling deadline reached. Resume GET for ${submission.id}; do not POST again.`,
  );
}

console.log(`status=${task.status} credits=${task.usage.credits}`);

if (task.status === 'failed') {
  const credits = task.usage?.credits ?? 'unknown';
  throw new Error(
    `${task.error?.code || 'task_failed'}: ${task.error?.message || 'unknown error'}; task=${task.id}; settled_credits=${credits}`,
  );
}

const outputUrl = task.output?.image_urls?.[0];
if (!outputUrl) throw new Error('Task completed without an image URL.');

const imageResponse = await fetch(outputUrl, {
  signal: AbortSignal.timeout(30_000),
});
if (!imageResponse.ok) {
  throw new Error(`Image download failed: HTTP ${imageResponse.status}`);
}

const contentType = (imageResponse.headers.get('content-type') || '')
  .split(';')[0]
  .trim()
  .toLowerCase();
const extensionByType = {
  'image/jpeg': 'jpg',
  'image/png': 'png',
  'image/webp': 'webp',
};
const extension = extensionByType[contentType];
if (!extension) throw new Error(`Unexpected output type: ${contentType}`);
const outputPath = `product-candidate.${extension}`;

await writeFile(outputPath, Buffer.from(await imageResponse.arrayBuffer()));
console.log(`saved ${outputPath} from ${outputUrl}`);

export REAPI_API_KEY="rk_live_replace_me"
export SOURCE_IMAGE_URL="https://assets.example.com/my-product.jpg"
export IMAGE_MODEL="nano-banana-2-lite"
node product-photo.mjs

{
  "task_id": "task_replace_me",
  "decision": "reject",
  "passed": [
    "1つの商品",
    "完全なトリミング",
    "背景",
    "コンタクトシャドウ"
  ],
  "failed": [
    "ポンプがより高くなりました",
    "下のコバルトバンドが上向きに移動しました"
  ],
  "usage_credits": 15,
  "reviewer": "initials",
  "prompt_revision": 1
}

承認済み画像あたりのコスト =
  完了した創造的試行のための決算クレジット合計 × $0.001
  --------------------------------------------------------
                承認された画像数

(15 + 15 + 15) × $0.001 / 1 承認画像 = $0.045

15 + 30 + 32 = 77 credits = $0.077