Start Composite Merge — Timestamp Watermark - API

Mode: timestampLive ticking clock — 1 video second = 1 wall second

Recorded 2026-05-05 10:00:00 IST

PREVIEW · composite-merge.mp4

Required

startTime

Default position

top-right

Clock advances

1s video = 1s clock

Start a composite-merge transcoding job and burn a live ticking clock onto the output. The clock starts at watermark.startTime and advances in real time (1 second of video = 1 second on the clock). Same endpoint as Start Composite Merge — the only difference is the watermark body parameter is set to type: "timestamp".

HTTP method and endpoint

POST

|

https://api.videosdk.live/v2/transcodings/merge

Headers Parameters

Authorization

REQUIRED

values: YOUR_TOKEN_WITHOUT_ANY_PREFIX

This will be a JWT token generate using VideoSDK ApiKey and Secret.

Note that the token will not include any prefix such as "Basic " or "Bearer ". Just pass a token as value.

You can generate a new token by refering this Guide: Generate Auth token

Content-Type

REQUIRED

values: application/json

This is usefull for json body parameters, so that VideoSDK servers can understand that the incoming body parameter will be a JSON string.

Body Parameters

recordingIds

REQUIRED

Array of participant recordingIds to merge. Must be a non-empty array of unique IDs that belong to the requesting user.

webhookUrl

OPTIONAL

Webhook URL to receive composite-merge-started, composite-merge-completed, composite-merge-failed and composite-merge-cancelled events.

watermark.type

REQUIRED

Must be the literal string timestamp for this variant.

watermark.startTime

REQUIRED

Clock origin. Auto-detected by format: 13-digit number = epoch ms, 10-digit number = epoch seconds, anything else parsed as ISO 8601. Examples: 1746439200000, 1746439200, "2026-05-05T10:00:00".

watermark.textConfig.position

OPTIONAL

defaultValue: top-right

Allowed: top-left | top-right | bottom-left | bottom-right | center.

watermark.textConfig.margin

OPTIONAL

defaultValue: 20

Pixels from edge (>= 0). Ignored when position is center.

watermark.textConfig.fontSize

OPTIONAL

defaultValue: 24

Pixels.

watermark.textConfig.color

OPTIONAL

defaultValue: white

FFmpeg color name (white, red, yellow, …) or #RRGGBB hex.

watermark.textConfig.background

OPTIONAL

defaultValue: black@0.3

"color@alpha" (e.g. "black@0.3", "white@0.5") or "none" to disable the background box.

watermark.textConfig.prefix

OPTIONAL

defaultValue: ""

Text prepended to the clock value.

watermark.textConfig.suffix

OPTIONAL

defaultValue: ""

Text appended to the clock value.

watermark.textConfig.format

OPTIONAL

defaultValue: "%Y-%m-%d %H:%M:%S"

strftime format string. Common tokens: %Y 4-digit year, %m month (01–12), %d day (01–31), %b short month name, %a short day name, %H hour (00–23), %M minute (00–59), %S second (00–59), %p AM/PM, %Z timezone name.

POST

|

https://api.videosdk.live/v2/transcodings/merge

NodeJS

• cURL
• NodeJS
• PHP
• Python

import fetch from 'node-fetch';
const options = {
	method: "POST",
	headers: {
		"Authorization": "$YOUR_TOKEN",
		"Content-Type": "application/json",
	},
	body: JSON.stringify({
	"recordingIds": [
		"6697685c6eaaaac67ea18130",
		"6697685c6eaaaac67ea18131"
	],
	"webhookUrl": "https://www.example.com/",
	"watermark": {
		"type": "timestamp",
		"startTime": "2026-05-05T10:00:00",
		"textConfig": {
			"position": "top-right",
			"margin": 20,
			"fontSize": 24,
			"color": "white",
			"background": "black@0.3",
			"prefix": "Recorded ",
			"suffix": " IST",
			"format": "%Y-%m-%d %H:%M:%S"
		}
	}
}),
};
const url= `https://api.videosdk.live/v2/transcodings/merge`;
const response = await fetch(url, options);
const data = await response.json();
console.log(data);

RESPONSE

{
  "id": "665fcf7f2abe9a2807e42700",
  "recordingIds": [
    "6697685c6eaaaac67ea18130",
    "6697685c6eaaaac67ea18131"
  ],
  "roomId": "abcd-efgh-ijkl",
  "sessionId": "6847c231fbaa8b416bc87014",
  "status": "processing",
  "task": "composite-merge",
  "startedAt": "2025-06-10T05:45:02.730Z"
}