视频生成

POST /v1/videos · GET /v1/videos/{id} · DELETE /v1/videos/{id}

根据文本提示词生成短视频,可选传入首/尾参考帧控制画面。这是业界标准 create + poll 形态的异步任务 API:POST /v1/videos 约 2 秒返回任务对象,轮询至完成;加 Prefer: wait 头可让快速生成一次调用直达结果。Seedance 系列模型,一把 API key,计费与其他端点一致。

端点与任务生命周期

一个任务资源,四种操作。任务状态流转:queued → in_progress → 终态之一(completed、failed 或 cancelled)。创建响应自带 status_url / cancel_url 链接,无需手工拼 URL。

同步糖 —— Prefer: wait

在创建请求上加 Prefer: wait 或 Prefer: wait=N 头(N 限制在 1..60 秒),网关会保持连接等待。任务在窗口内完成则直接返回终态对象——含视频 URL 与用量,无需轮询;未在窗口内完成则优雅降级:返回当前状态对象(不报错,任务照常运行),继续正常轮询即可。

请求体

可用模型

模型可用性取决于你的部署。通过 GET /v1/videos/models获取实时、合规感知的完整列表(含每模型分辨率/时长约束与价格)。当前阵容:

价格:USD / 1M video tokens。seedance-1-5-pro-251215 开音轨(generate_audio: true,默认)$2.4、关音轨 $1.2;其余模型按分辨率档单一费率。

video token 与定价

视频按 video token 计费,由实际输出推导:tokens ≈ 宽 × 高 × 24 fps × 秒 / 1024。费率按每 1M video tokens 计,以实际生效参数(completed 任务中回显)为准——因此 ratio: "adaptive" 与 duration: -1 都按模型实际产出计费。

直观锚点(seedance-1-5-pro-251215 有声):480p / 16:9 / 4 秒 ≈ 40.6K video tokens ≈ $0.10;720p / 5 秒 ≈ 108.9K tokens ≈ $0.26。

计费

仅成功才计费:任务首次到达 completed 时结算一次,按回传的 video token 用量计价。失败任务(含内容审核拒绝)与取消任务一律不收费——上游错误原样透传,便于定位原因。

示例 —— curl 一步到位(Prefer: wait)

curl https://synthorai.io/v1/videos \
  -H "Authorization: Bearer $SYNTHORAI_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Prefer: wait=60" \
  -d '{
    "model": "seedance-1-0-pro-fast-251015",
    "prompt": "A corgi puppy chasing a butterfly across a meadow, cinematic",
    "resolution": "480p",
    "ratio": "16:9",
    "duration": 4
  }'

# Finished inside the wait window → the terminal object comes straight back:
{
  "id": "vid_6091d8d1af805818b1470488",
  "object": "video",
  "model": "seedance-1-0-pro-fast-251015",
  "status": "completed",
  "data": [{ "url": "https://…tos….mp4?…" }],
  "usage": { "completion_tokens": 40594, "total_tokens": 40594 },
  "resolution": "480p", "ratio": "16:9", "duration": 4, "fps": 24,
  "seed": 34142
}
# Not done in time → the current status object is returned instead (no error,
# the task keeps running) — continue polling status_url as usual.

示例 —— curl 创建 + 轮询

# 1) Create — returns in ~2 s with a queued task object
curl https://synthorai.io/v1/videos \
  -H "Authorization: Bearer $SYNTHORAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-1-5-pro-251215",
    "prompt": "A corgi puppy chasing a butterfly across a meadow, cinematic",
    "resolution": "720p",
    "duration": 5,
    "generate_audio": true
  }'

{
  "id": "vid_6091d8d1af805818b1470488",
  "object": "video",
  "model": "seedance-1-5-pro-251215",
  "status": "queued",
  "created_at": 1784619862,
  "status_url": "https://synthorai.io/v1/videos/vid_6091d8d1af805818b1470488",
  "cancel_url": "https://synthorai.io/v1/videos/vid_6091d8d1af805818b1470488"
}

# 2) Poll until status is terminal (completed | failed | cancelled)
curl https://synthorai.io/v1/videos/vid_6091d8d1af805818b1470488 \
  -H "Authorization: Bearer $SYNTHORAI_API_KEY"

{
  "id": "vid_6091d8d1af805818b1470488",
  "object": "video",
  "model": "seedance-1-5-pro-251215",
  "status": "completed",
  "data": [{ "url": "https://…tos….mp4?…" }],
  "usage": { "completion_tokens": 108900, "total_tokens": 108900 },
  "resolution": "720p", "ratio": "16:9", "duration": 5, "fps": 24,
  "seed": 34142, "generate_audio": true
}

# 3) Download the video — the URL is pre-signed (no auth header) and expires
#    in ~24 h: fetch promptly and re-host if you need it long-term.
curl -o out.mp4 "https://…tos….mp4?…"

示例 —— Python(requests)

import time
import requests

BASE = "https://synthorai.io/v1"
HEADERS = {"Authorization": "Bearer YOUR_API_KEY"}

task = requests.post(f"{BASE}/videos", headers=HEADERS, json={
    "model": "seedance-1-5-pro-251215",
    "prompt": "A corgi puppy chasing a butterfly across a meadow, cinematic",
    "resolution": "720p",
    "duration": 5,
}).json()

while task["status"] not in ("completed", "failed", "cancelled"):
    time.sleep(5)
    task = requests.get(task["status_url"], headers=HEADERS).json()

if task["status"] == "completed":
    url = task["data"][0]["url"]  # pre-signed, valid ~24 h — re-host promptly
    with open("out.mp4", "wb") as f:
        f.write(requests.get(url).content)
else:
    print(task["error"])  # provider code + message, passed through verbatim

示例 —— Node(fetch)

import fs from "node:fs";

const BASE = "https://synthorai.io/v1";
const HEADERS = { Authorization: `Bearer ${process.env.SYNTHORAI_API_KEY}` };

let task = await (await fetch(`${BASE}/videos`, {
  method: "POST",
  headers: { ...HEADERS, "Content-Type": "application/json" },
  body: JSON.stringify({
    model: "seedance-1-5-pro-251215",
    prompt: "A corgi puppy chasing a butterfly across a meadow, cinematic",
    resolution: "720p",
    duration: 5,
  }),
})).json();

while (!["completed", "failed", "cancelled"].includes(task.status)) {
  await new Promise((r) => setTimeout(r, 5000));
  task = await (await fetch(task.status_url, { headers: HEADERS })).json();
}

if (task.status === "completed") {
  const url = task.data[0].url; // pre-signed, valid ~24 h — re-host promptly
  fs.writeFileSync("out.mp4", Buffer.from(await (await fetch(url)).arrayBuffer()));
} else {
  console.error(task.error); // provider code + message, passed through verbatim
}

幂等性

传 X-Idempotency-Key 请求头让重试安全:相同 key 的重复请求返回 409,而不会二次创建(和二次计费)任务。视频生成慢、易超时重试,这能防止重复扣费。