Request presigned URLs for the remaining chunks

This method generates new presigned URLs for specific chunks that require uploading. Use this endpoint in the following situations:

Your initial URLs have expired (URLs expire after one hour).
The initial set of presigned URLs does not include URLs for all chunks.
You need to retry failed chunk uploads with new URLs. To specify which chunks need URLs, use the start and count parameters. For example, to generate URLs for chunks 21 to 30, use start=21 and count=10. The response will provide new URLs, each with a fresh expiration time of one hour.

This method generates new presigned URLs for specific chunks that require uploading. Use this endpoint in the following situations: - Your initial URLs have expired (URLs expire after one hour). - The initial set of presigned URLs does not include URLs for all chunks. - You need to retry failed chunk uploads with new URLs. To specify which chunks need URLs, use the `start` and `count` parameters. For example, to generate URLs for chunks 21 to 30, use `start=21` and `count=10`. The response will provide new URLs, each with a fresh expiration time of one hour.

Authentication

x-api-keystring

Your API key.

Note

You can find your API key on the API Key page.

Your API key. <Note title="Note"> You can find your API key on the <a href="https://playground.twelvelabs.io/dashboard/api-key" target="_blank">API Key</a> page. </Note>

Path Parameters

upload_idstringRequired

The unique identifier of the upload session.

Request

This endpoint expects an object.

startintegerRequired>=1

The index of the first chunk number to generate URLs for. Chunks are numbered from 1.

countintegerRequired1-50

The number of presigned URLs to generate starting from the index. You can request a maximum of 50 URLs in a single API call.

Response

Additional presigned URLs have been successfully generated.

upload_idstring or null

The unique identifier of the upload session associated with these URLs.

start_indexinteger or null

The index of the first chunk number in this set of URLs. Matches the start value from your request.

countinteger or null

The number of new URLs created. Matches the count value from your request.

upload_urlslist of objects or null

An array of additional presigned URLs for uploading chunks.

generated_atstring or nullformat: "date-time"

The date and time, in the RFC 3339 format (“YYYY-MM-DDTHH:mm:ssZ”), when these URLs were created. URLs remain valid for 1 hour from this time.

expires_atstring or nullformat: "date-time"

A string representing the date and time, in RFC 3339 format (“YYYY-MM-DDTHH:mm:ssZ”), when the resource will expire.

1	curl -X POST https://api.twelvelabs.io/v1.3/assets/multipart-uploads/507f1f77bcf86cd799439011/presigned-urls \
2	-H "x-api-key: <apiKey>" \
3	-H "Content-Type: application/json" \
4	-d '{
5	"start": 1,
6	"count": 10
7	}'

1	{
2	"upload_id": "507f1f77bcf86cd799439011",
3	"start_index": 1,
4	"count": 10,
5	"upload_urls": [
6	{
7	"chunk_index": 1,
8	"url": "https://s3.amazonaws.com/bucket/key?signature=...",
9	"expires_at": "2025-12-01T18:00:00Z"
10	}
11	],
12	"generated_at": "2025-12-01T11:30:00Z",
13	"expires_at": "2025-12-01T18:00:00Z"
14	}

Authentication

Note

Path Parameters

Request

Response

Errors

Note