Conditional video writing in gstreamer

Newcomers
1

Hello,

I’m learning GStreamer and I have some questions regarding it. I’m planning to write an application which captures rtsp video via GStreamer and writes a video to a file. The video shouldn’t be recorded all the time but according to the certain conditions (according to a timetable, an external command, etc.). How can I implement it?

I’m writing in Python because it’s the language I’m familiar with. I know it’s possible to define a pipeline with appsink (something similar to this example). I can retrieve a raw RGB frame by defining a corresponding pipeline and then write a video via such libraries as OpenCV or PyAV. However, I as far as my knowledge goes, those libraries rely heavily on ffmpeg to write video files and I’m not sure it’s a good idea to mix those two media frameworks in a single app. Are there any ways to do it in more “gstreamer native” way?

2

You could use GStreamer for this as well. Pipelines are not static but can be changed at runtime, so you could e.g. add/remove a branch to/from a tee element somewhere which would encode and write to a file whenever needed.

There’s of course also no problem with using an appsink and then using some non-GStremer code to write the files, but that sounds like it would just complicate the whole application if there’s no real reason to do it externally.