Can I use individual features headlessly, without opening the editor UI?
Yes. All three products can produce edited output with the editor closed. How much you can drive purely in code differs, and CE.SDK gives you the most.
Each of the three products can apply edits and return finished output without the editor interface on screen. What changes is how much you can build and control in code. CE.SDK gives you a complete engine to run from start to finish, while PE.SDK and VE.SDK focus that headless capability on rendering and export.
CE.SDK
It runs a full headless engine you can drive entirely in code. Run the engine on its own in the browser, or use the @cesdk/node package when you work on the server. Either way you apply individual features such as cropping, filters, and effects with no interface loaded, because the engine handles the editing on its own.
This is also how rendering and export work on the server, which means it is the option to choose when you need output at scale or without an editor. For setup, see headless mode in the browser and headless mode on Node.js.
PE.SDK
It can produce output outside the editor UI on both iOS and Android, with a route suited to each platform.
On iOS, you hold the changes in a PhotoEditModel and pass it to a PhotoEditRenderer, which generates the final image in code. This lets you apply edits such as filters and overlays and export the result without ever showing the editor. For the full example, see headless rendering.
On Android, the same output comes from background export. You capture the edits as a SettingsList and render them in a WorkManager job using the backend:headless module, which keeps the render off the editor. For the setup, see background export.
VE.SDK
It supports headless output through background export on Android. The render runs in a WorkManager job using the backend:headless module, the same one PE.SDK uses, and returns a finished video with the editor closed. For the setup, see background export.
For headless video on iOS, or to drive video rendering in code across platforms, use CE.SDK's engine, which runs headless across web, server, and mobile.