# Clamp - Dynamic stream captions on live streams

**URL:** <https://community.wowza.com/t/clamp-dynamic-stream-captions-on-live-streams/42724>\
**Category:** Wowza Developer Dojo\
**Created:** [January 6, 2015, 11:20pm UTC](https://community.wowza.com/t/clamp-dynamic-stream-captions-on-live-streams/42724 "2015-01-06T23:20:10Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![system](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/system/32/447_2.png) [@system](https://community.wowza.com/u/system)\
**Post date:** [January 6, 2015, 11:20pm UTC](https://community.wowza.com/t/clamp-dynamic-stream-captions-on-live-streams/42724/1 "2015-01-06T23:20:10Z")

</div>

Hi,

I am pleased to announce the initial release of [Clamp](https://streamtoolbox.com/clamp), the latest tool in my [streamtoolbox.com](https://streamtoolbox.com).

Clamp is based on Transcoder AddOn and currently capable of keeping an eye on a single text file and process any new instructions added in this file during streaming. The caption instructions need to be specified in JSON format, e.g.

```auto
# An example caption source file for Clamp
{start: "2015.01.05 21:13:45.002", duration: 15, text: "Hello Clamp!", position: {x: 10, y: 50}, style: {font:"Verdana",size:50,style:"bold",color: "yellow"}}

```

On my roadmap I have many features to add, this is the initial announcement, which I will keep updated going forward.

[video=youtube;quTyvWa6kD0][https://www.youtube.com/watch?v=quTyvWa6kD0[/video]](https://www.youtube.com/watch?v=quTyvWa6kD0%5B/video%5D)