# Index faces from a photo

> Detects all quality-gated faces in an image and stores them in the collection (Rekognition IndexFaces). (POST /v1/collections/{id}/index)

Source: https://sightradar.com/docs/api/faces/index-faces-from-a-photo

Detects all quality-gated faces in an image and stores them in the
collection (Rekognition `IndexFaces`). Provide the image as JSON `{url}` / `{gcsKey}`, a multipart `file`, or
raw image bytes. Optional `photoId` is the per-image key (defaults to a
content hash).

### Example request

```bash
curl -X POST "https://api.sightradar.com/v1/collections/$ID/index" \
  -H "Authorization: Bearer $SR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com/photo.jpg"}'
```

### Parameters

| Name              | In     | Type     | Description                                                                                                                                                                                                                    |
| ----------------- | ------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `id` **required** | path   | `string` |                                                                                                                                                                                                                                |
| `photoId`         | query  | `string` | Per-image key (also accepted in body).                                                                                                                                                                                         |
| `Idempotency-Key` | header | `string` | Opt-in idempotency. A replay under the same key is never re-charged. For a selfie register it returns 200 with the stored result (Idempotent-Replay: true) when the registration identity matches; every other op returns 409. |

### Request body (application/json)

| Field     | Type     | Description                      |
| --------- | -------- | -------------------------------- |
| `url`     | `string` | Public image URL.                |
| `gcsKey`  | `string` | Google Cloud Storage object key. |
| `photoId` | `string` | Optional per-image key.          |

Also accepts: `multipart/form-data`, `application/octet-stream`.

### Response body

| Field                 | Type       | Description                     |
| --------------------- | ---------- | ------------------------------- |
| `collection_id`       | `string`   |                                 |
| `photo_id`            | `string`   |                                 |
| `indexed`             | `integer`  | Faces stored.                   |
| `detected_face_count` | `integer`  |                                 |
| `rejected_face_count` | `integer`  | Detected but quality-gated out. |
| `faces`               | `object[]` |                                 |
| `model_version`       | `string`   |                                 |

### Status codes

| Status | Meaning                                                                |
| ------ | ---------------------------------------------------------------------- |
| `200`  | Faces indexed.                                                         |
| `400`  | Cannot decode image, or no url/gcsKey/body provided.                   |
| `401`  | Missing or invalid API key.                                            |
| `402`  | Wallet balance too low for this operation.                             |
| `409`  | A request with this Idempotency-Key is in flight or already processed. |
| `413`  | Image exceeds the 30 MB encoded size cap.                              |
| `429`  | Per-key RPS or per-customer concurrency limit exceeded.                |
| `502`  | Engine error (the credit hold is refunded automatically).              |