Edit-service plugin

I want to write a plugin for reverse the capture. But it seems there is no API for using the built-in FFmpeg module.

Use story for the kap-reverse:

1. Use Kap to record a movie segment
2. Then use kap-reverse to get a funny GIF or MP4 file

Also, I think it will be useful for others.

[sindresorhus]

Your use-case doesn’t really fit the current plugin API as they are meant to be “share” plugins. If you implement kap-reverse as a share plugin, the user won’t be able to, for example, upload the reversed video to Giphy.

For this use-case, we need a new type of plugin target, an editService. These kinds of plugins would receive the raw captured video and be able to modify the video before it’s passed to the shareService plugins. Some use-cases I can think of: adding watermark, brightness/shadow changes, filters, reverse video, annotations, etc. This would allow people to create plugins for pretty much anything that FFmpeg can do. The harder part of this is to figure out how we enable plugins to create UIs for their options/controls. At first we could maybe only allow non-configurable edit actions and then expand it in the future.

We can discuss here, but this definitely a Kap v4 kinda feature, so it won’t be done in the near future.

[karaggeorge]

I think that’s a good idea (having a different type of plugin). I don’t think Kap should take care of providing a UI (some might not need a UI). Maybe those plugins can be of the same format as we have them now (exporting an action and schema). The schema would be controlled in the preferences window like it is now for the rest of the plugins, and the action would accept the path to the original file and a new temp path. When it’s done the new temp path should have the “finished” version of that plugin. And then we can feed that file to either an export-type plugin or even chain it with more edit-service plugins. (i.e one of them reverses the video, the next one adds a slow-motion effect and then we pass to an export option). So you could have the user pick as many chainable plugins as they need.