Head Swap – Analyze
namifusion/head-swap/analyze
Detect and track heads in a video with SAM3. Returns a head list with preview images and a track manifest for the generate step.
Examples
Parameters
| Name | Type | Default | Constraints | Description |
|---|---|---|---|---|
| resolutionResolution | select | 720p | 480p | 720p |
Output fields
| Field | Type | Description |
|---|---|---|
| objects | array | Detected heads: obj_id, preview url, masked_url, coverage, representative_frame, bbox |
| video_info | object | Input video info: width/height/fps/frame_count |
| analysis_id | string | Analysis session id |
| detected_objects | number | Number of detected heads |
| track_manifest_url | string | Track manifest URL - pass it to the generate model |
API
Call this model through one unified REST API. Get a key on the API Keys page.
cURL
# 1) Submit — returns { "task_uuid": "..." }
curl -X POST "https://www.namifusion.com/api/v1/marketplace/run/namifusion/head-swap/analyze" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"input": {
"resolution": "720p"
}
}'
# 2) Poll until status is "completed", then read the output URLs
curl "https://www.namifusion.com/api/v1/marketplace/run/tasks/TASK_UUID" \
-H "Authorization: Bearer YOUR_API_KEY"Python
import time, requests
API_KEY = "YOUR_API_KEY"
HEADERS = {"Authorization": f"Bearer {API_KEY}"}
# 1) Submit
resp = requests.post(
"https://www.namifusion.com/api/v1/marketplace/run/namifusion/head-swap/analyze",
headers=HEADERS,
json={
"input": {
"resolution": "720p"
}
},
)
resp.raise_for_status() # 401/402/429/5xx stop here instead of polling a bad task
task = resp.json()
# 2) Poll until a terminal state (completed / failed / cancelled).
# This model is allowed up to 1800s server-side.
deadline = time.time() + 1860
while task.get("status") not in ("completed", "failed", "cancelled"):
if time.time() > deadline:
raise TimeoutError(f"still {task.get('status')} — keep the task_uuid and poll later")
time.sleep(3)
poll = requests.get(f"https://www.namifusion.com/api/v1/marketplace/run/tasks/{task['task_uuid']}", headers=HEADERS)
poll.raise_for_status()
task = poll.json()
print(task["status"], task.get("output"))JavaScript
const API_KEY = "YOUR_API_KEY";
const HEADERS = { Authorization: `Bearer ${API_KEY}` };
// 1) Submit
const resp = await fetch("https://www.namifusion.com/api/v1/marketplace/run/namifusion/head-swap/analyze", {
method: "POST",
headers: { ...HEADERS, "Content-Type": "application/json" },
body: JSON.stringify({
"input": {
"resolution": "720p"
}
}),
});
if (!resp.ok) throw new Error(`submit failed: ${resp.status} ${await resp.text()}`);
let task = await resp.json();
// 2) Poll until a terminal state (completed / failed / cancelled).
// This model is allowed up to 1800s server-side.
const deadline = Date.now() + 1860 * 1000;
while (!["completed", "failed", "cancelled"].includes(task.status)) {
if (Date.now() > deadline) throw new Error(`still ${task.status} — keep the task_uuid and poll later`);
await new Promise((r) => setTimeout(r, 3000));
const poll = await fetch(`https://www.namifusion.com/api/v1/marketplace/run/tasks/${task.task_uuid}`, { headers: HEADERS });
if (!poll.ok) throw new Error(`poll failed: ${poll.status}`);
task = await poll.json();
}
console.log(task.status, task.output);Documentation
Head Swap – Analyze
Step 1 of the head swap pipeline. Detects and tracks heads in the input video.
Input
| Field | Type | Required | Notes |
|---|---|---|---|
| video_url | string (video URL) | yes | Up to 30 seconds, 480p/720p processing |
| resolution | "480p" | "720p" | no | Default 720p; must match the generate step |
Output
objects[]: detected heads —obj_id, previewurl,masked_url,coveragetrack_manifest_url: pass this tonamifusion/head-swap/generatevideo_info: width/height/fps/frame_count
Typical flow
- POST /run/namifusion/head-swap/analyze with your video
- Poll GET /run/tasks/{task_uuid} until completed
- Pick the obj_id(s) you want to replace from
objects - Call namifusion/head-swap/generate with
track_manifest_url+mappings
Pricing: 5 credits per call.
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