bytedance/seedream-4.0/text-to-image5クレジットから /枚· 画像を作成Seedream 4.0 は 5.0 より前の世代の Seedream で、1〜10枚の参考からのテキストから画像と編集に対応し、1024×1024から4096×2304まで16種類の固定サイズがあります。どのサイズでも料金は同じなので、最初から納品サイズで描画できます。
POST /jobs/createTask でモデル名に bytedance/seedream-4.0/text-to-image を指定すれば呼び出せます。5クレジット/枚から($0.05)。新規アカウントには 30 クレジットが付くので、まず Playground で無料で試せます。
- 画像を作成
- 画像を編集
- 参照画像は最大10枚
bytedance/seedream-4.0/text-to-imagePOST https://api.popnow.ai/api/v1/jobs/createTask# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(uuidgen)"
curl -X POST https://api.popnow.ai/api/v1/jobs/createTask \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-H "Idempotency-Key: $IDEMPOTENCY_KEY" \
-d '{
"model": "bytedance/seedream-4.0/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"size": "2048*2048"
}
}'
# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $POPNOW_API_KEY"// Node 18+ (or any runtime with fetch). Keep the API key on your server.
const BASE = "https://api.popnow.ai/api/v1";
const headers = { Authorization: `Bearer ${process.env.POPNOW_API_KEY}` };
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));
async function call(path, init = {}) {
const res = await fetch(BASE + path, { ...init, headers: { ...headers, ...init.headers } });
const body = await res.json();
if (body.code !== 200) throw new Error(`${body.code} ${body.msg}`);
return body.data;
}
const { taskId } = await call("/jobs/createTask", {
method: "POST",
headers: { "Content-Type": "application/json", "Idempotency-Key": crypto.randomUUID() },
body: JSON.stringify({
"model": "bytedance/seedream-4.0/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"size": "2048*2048"
}
}),
});
// Poll with backoff. A finished task may still be copying files: wait while an asset is pending.
let task;
for (let delay = 2000; ; delay = Math.min(delay * 1.5, 15000)) {
await sleep(delay);
task = await call(`/jobs/recordInfo?taskId=${taskId}`);
const copying = (task.output?.assets ?? []).some((a) => a.pending && !a.unavailable);
if (["succeeded", "failed", "canceled", "expired"].includes(task.state) && !copying) break;
}
if (task.state !== "succeeded") throw new Error(`${task.state}: ${task.errorMessage ?? "no detail"}`);
// Each asset has a signed url (no API key needed) that expires at expiresAt: save the file.
for (const asset of task.output.assets) console.log(asset.url);import os, time, uuid, requests
BASE = "https://api.popnow.ai/api/v1"
HEADERS = {"Authorization": f"Bearer {os.environ['POPNOW_API_KEY']}"}
def call(method, path, **kwargs):
body = requests.request(method, BASE + path, headers={**HEADERS, **kwargs.pop("headers", {})}, timeout=30, **kwargs).json()
if body["code"] != 200:
raise RuntimeError(f'{body["code"]} {body["msg"]}')
return body["data"]
task_id = call(
"POST",
"/jobs/createTask",
headers={"Idempotency-Key": str(uuid.uuid4())}, # reuse it if you retry
json={
"model": "bytedance/seedream-4.0/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"size": "2048*2048"
}
},
)["taskId"]
# Poll with backoff. A finished task may still be copying files: wait while an asset is pending.
delay = 2.0
while True:
time.sleep(delay)
task = call("GET", "/jobs/recordInfo", params={"taskId": task_id})
assets = (task.get("output") or {}).get("assets") or []
copying = any(a.get("pending") and not a.get("unavailable") for a in assets)
if task["state"] in ("succeeded", "failed", "canceled", "expired") and not copying:
break
delay = min(delay * 1.5, 15.0)
if task["state"] != "succeeded":
raise RuntimeError(f'{task["state"]}: {task.get("errorMessage", "no detail")}')
# Each asset has a signed url (no API key needed) that expires at expiresAt: save the file.
for asset in assets:
print(asset["url"])input は下のスキーマから作っているので、このままで検証を通ります。プロンプトとリンクを自分のものに替えてください。
料金
| オプション | クレジット /枚 | ≈ USD |
|---|---|---|
| 標準 | 4.5 | $0.045 |
1クレジット = $0.01 · すべてのオプションと料金:GET /models/bytedance/seedream-4.0/text-to-image
タスクごとにクレジットは整数に切り上げられるため、最安の設定で 1 回実行すると 5クレジット/枚($0.05)です。
パラメーター
これらのフィールドは、すべてのリクエストの検証に使っているのと同じスキーマから来ています。ここにないフィールドは拒否されます。
promptstring必須Describe the image to generate: subject, composition, style, and lighting.
sizestring任意Output image size in pixels, written as width*height.
JSON スキーマ(原文)
{
"type": "object",
"required": [
"prompt"
],
"properties": {
"size": {
"enum": [
"2048*2048",
"1024*1024",
"2304*1728",
"1728*2304",
"2848*1600",
"1600*2848",
"2496*1664",
"1664*2496",
"3136*1344",
"3072*3072",
"3456*2592",
"2592*3456",
"4096*2304",
"2304*4096",
"2496*3744",
"3744*2496"
],
"type": "string",
"default": "2048*2048",
"description": "Output image size in pixels, written as width*height."
},
"prompt": {
"type": "string",
"minLength": 1,
"description": "Describe the image to generate: subject, composition, style, and lighting."
}
},
"additionalProperties": false
}Seedream 4.0で作った実例

Cinematic wide shot, an adult woman in a black leather trench coat leaning on a rooftop railing at night, a rain-hazed city of glowing windows and abstract neon light tubes stretching behind her, magenta and teal reflections on wet concrete, anamorphic lens flare, subject placed on the left third. No signs, no text, no lettering, no logos.
{
"model": "bytedance/seedream-4.0/text-to-image",
"input": {
"prompt": "Cinematic wide shot, an adult woman in a black leather trench coat leaning on a rooftop railing at night, a rain-hazed city of glowing windows and abstract neon light tubes stretching behind her, magenta and teal reflections on wet concrete, anamorphic lens flare, subject placed on the left third. No signs, no text, no lettering, no logos.",
"size": "4096*2304"
}
}レスポンス、ポーリング、コールバック
どのモデルも使い方は同じです。タスクを作成し、ポーリングするかコールバックを待ちます。
先に見積もる
curl -X POST https://api.popnow.ai/api/v1/jobs/quote \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "bytedance/seedream-4.0/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"size": "2048*2048"
}
}'本文は createTask と同じです。想定される請求額と最大の請求額を返し、何も実行しません。
受付済み
HTTP/1.1 202 Accepted
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"state": "queued"
},
"request_id": "req_example_create"
}HTTP 202 はタスクを受け付けたという意味です。クレジットは確保されただけで、まだ引き落とされていません。最終的な請求額が確保額を超えることはありません。
状態の確認
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $POPNOW_API_KEY"間隔を少しずつ空けながら数秒ごとに確認し、state が succeeded、failed、canceled、expired のいずれかになったら止めます。
完了したタスク
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"model": "bytedance/seedream-4.0/text-to-image",
"state": "succeeded",
"output": {
"assets": [
{
"url": "https://cdn.popnow.ai/tasks/task_01k3m8x9q2z4v7n5p6r8s0t1w3/output.png?signature=FROM_RESPONSE",
"expiresAt": "2026-10-17T12:20:00Z",
"mime": "image/png",
"width": 1024,
"height": 1024
}
]
},
"settled": true
},
"request_id": "req_example_record"
}expiresAt までに url からダウンロードしてください。あとで新しいリンクが必要なら POST /common/download-url を使います。
コールバックを検証する
import { createHash, createHmac, timingSafeEqual } from "node:crypto";
import express from "express";
const app = express();
// express.raw keeps the exact bytes that were signed; express.json would not match.
app.post("/hooks/popnow", express.raw({ type: "application/json" }), (req, res) => {
const timestamp = req.header("X-Webhook-Timestamp");
const signature = req.header("X-Webhook-Signature") ?? "";
const body = JSON.parse(req.body.toString("utf8"));
const taskId = body.data?.taskId ?? body.task_id;
const digest = createHash("sha256").update(req.body).digest("hex");
const expected = createHmac("sha256", process.env.POPNOW_WEBHOOK_SECRET)
.update(`${taskId}.${timestamp}.${digest}`)
.digest("base64");
const ok = expected.length === signature.length && timingSafeEqual(Buffer.from(expected), Buffer.from(signature));
// Check the signature first, then reject anything older than five minutes.
if (!ok || Math.abs(Date.now() / 1000 - Number(timestamp)) > 300) return res.status(401).end();
res.status(200).end(); // answer fast, then fetch the task and store its files
});callBackUrl を指定すると、完了したタスクをお送りします。信頼する前に、生のリクエスト本文で署名を確認してください。
ローカルファイルを送る
curl -X POST https://api.popnow.ai/api/v1/common/upload-url \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-d '{"contentType": "image/png", "bytes": 482113}'
# PUT the file bytes to data.uploadUrl with every header in data.headers, then commit it:
curl -X POST https://api.popnow.ai/api/v1/files/$FILE_ID/commit \
-H "Authorization: Bearer $POPNOW_API_KEY"
# The commit returns a popnow://f/... reference. Put it in any image, video or
# audio field of the task input instead of a public https URL.公開 https リンクはそのまま使えます。ローカルファイルは先に upload-url と commit を通します。

