I've had lots of problem to even convert the AVCHD files from the HD camera at all at first. But now that totally changed.
Openshot is a really new and really great video editor that's based on ffmpeg and can read my .m2ts files without a problem. I can deinterlace them and cut them together for output in almost any format from FullHD to QCIF.
The problem is that at least version 1.1 had a slight issue with memory leaks. It grew to consume more and more RAM. So I recommend to close and reopen it before doing the encode. Or you just close it and do the encode with the command line program openshot-renderer! That also means you can easily edit the video on one computer and then encode it on some other computer, e.g. a headless server. And Openshot encodes pretty quickly as well. Even on my slow old notebook I can export from FullHD in a very short amount of time!
Video editing has never been this easy, fun and fast!
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