如何用 Claude Opus 5.5 和 Seedance 2.5 製作 AI 短片

export SEEDROUTER_API_KEY="your-key"

import os
import requests

HEADERS = {"Authorization": f"Bearer {os.environ['SEEDROUTER_API_KEY']}"}

import json
import anthropic

client = anthropic.Anthropic(
    api_key=os.environ["SEEDROUTER_API_KEY"],
    base_url="https://api.seedrouter.ai",
)

DIRECTOR = """You are the director of a short film made with AI models.
Return only JSON, no other text, in this shape:
{"character": "...", "sheet_prompt": "...",
 "shots": [{"duration": 5, "frame_prompt": "...", "video_prompt": "..."}]}

character: one fixed paragraph describing the main character's face, hair,
build and clothes. Repeat it word for word inside every other prompt.

sheet_prompt: an image prompt for one character reference sheet: a front,
three-quarter, profile and back view, plus four facial expressions, on a plain
light background, with no text other than small panel labels.

shots: 3 to 5 shots, each 4 to 15 seconds.
frame_prompt: an image prompt for the first frame of the shot.
video_prompt: a video prompt for Seedance 2.5. Write it in this order: subject
and action, scene, visual style, camera, audio. Image 1 is the character sheet
and Image 2 is the start frame of the shot; refer to them by those names.
Use one camera move per shot. Say who is holding the camera and how they move.
For shots longer than 5 seconds, split the action into time ranges such as
0-3s. Put dialogue in quotes as: Character's line (emotion): content.
Describe the ambient sound. Do not ask for subtitles or on-screen text.

The character must not look like a real, identifiable person. Use a stylized
look, such as a 3D animated or illustrated character."""

message = client.messages.create(
    model="claude-opus-5-5",
    max_tokens=16000,
    system=DIRECTOR,
    messages=[{
        "role": "user",
        "content": "A lighthouse keeper finds a lost robot on the rocks during a storm and teaches it to wave at passing ships.",
    }],
)
text = "".join(block.text for block in message.content if block.type == "text")
plan = json.loads(text)

import time

def image(prompt, size, refs=()):
    body = {"model": "gpt-image-2.5-flare", "prompt": prompt, "size": size, "quality": "high"}
    if refs:
        body["images"] = [{"image_url": url} for url in refs]
    task_id = requests.post(
        "https://api.seedrouter.ai/v1/images/generations",
        headers=HEADERS, json=body, timeout=60,
    ).json()["id"]
    while True:
        task = requests.get(
            f"https://api.seedrouter.ai/v1/tasks/{task_id}", headers=HEADERS, timeout=30,
        ).json()
        if task["status"] == "completed":
            return task["output"]["data"][0]["url"]
        if task["status"] == "failed":
            raise RuntimeError(task["error"]["message"])
        time.sleep(3)

sheet = image(plan["sheet_prompt"], "1536x1024")
frames = [image(shot["frame_prompt"], "1792x1008", [sheet]) for shot in plan["shots"]]

def shot(prompt, refs, duration):
    content = [{"type": "text", "text": prompt}]
    for url in refs:
        content.append({"type": "image_url", "image_url": {"url": url}, "role": "reference_image"})
    task_id = requests.post(
        "https://api.seedrouter.ai/v1/contents/generations/tasks",
        headers=HEADERS,
        json={
            "model": "dreamina-seedance-2-5",
            "content": content,
            "resolution": "480p",
            "ratio": "16:9",
            "duration": duration,
            "generate_audio": True,
        },
        timeout=60,
    ).json()["id"]
    while True:
        task = requests.get(
            f"https://api.seedrouter.ai/v1/contents/generations/tasks/{task_id}",
            headers=HEADERS, timeout=30,
        ).json()
        if task["status"] == "succeeded":
            return task["content"]["video_url"]
        if task["status"] in ("failed", "expired"):
            raise RuntimeError(task["error"]["message"])
        time.sleep(15)

videos = [shot(s["video_prompt"], [sheet, frame], s["duration"]) for s, frame in zip(plan["shots"], frames)]

names = []
for index, url in enumerate(videos):
    name = f"shot-{index + 1}.mp4"
    with open(name, "wb") as file:
        file.write(requests.get(url, timeout=300).content)
    names.append(name)
with open("shots.txt", "w") as file:
    file.writelines(f"file '{name}'\n" for name in names)

ffmpeg -f concat -safe 0 -i shots.txt -c copy film.mp4