问题
I've written a Gstreamer source plugin, it can produce buffers and transform to downstream elements and do preview. Recently I received a request to implement multi-stream, that one stream to do preview, and the other stream to do recording(using filesink, I suppose). I investigated 'tee' plugin before, but it turns out that it only supports multiple streams with the same formats/resolutions. What plugin should I use if two streams have different formats/resolutions, say, two capsfilters in one pipeline? If there are plugin could do that, could you provide some examples for how to use them?
the pipeline I expect goes like this:
gst-launch-1.0 mysrc ! (some plugins) name=t ! video/x-raw,format=NV12,width=320,height=240 ! xvimagesink t. ! video/x-raw,format=YUY2,width=640,height=480 ! filesink location=img_file
回答1:
I think either you implement this in your plugin which will produce two src pads and you will just connect the filesink and videosink correctly..
Or you will use tee and videoscale videoconvert videorate elements to achieve different resolutions. This approach is of course more resource demanding and the first approach may be better optimisable (just guessing, I dont know anything about your plugin).
This is example with two videosink each different size.. You have to realise that you have one input from your mysrc.. that is you have to duplicate it and then one of the branches have to be resized (or maybe two if you need).. there is no other way. What you want is element of combination of tee and videoscale/videorate/videoconvert.. I am not sure if there is such element, and I am not sure it would be very usable(but maybe it has sense, I just do not see it)..
gst-launch-1.0 videotestsrc ! video/x-raw,width=640,height=480 ! tee name=t t. ! queue ! videoscale ! video/x-raw,width=320,height=240 ! videoconvert ! autovideosink t. ! queue ! videoscale ! video/x-raw,width=200,height=200 ! videoconvert ! autovideosink
Maybe I just didnt understand your question.
来源：https://stackoverflow.com/questions/38067073/implement-multi-stream-in-gstreamer