Dealing with AVCHD / MPEG-TS files
At the time being, MPEG Transport Stream files (usually with file extensions such as .mts, .m2ts and sometimes .mpg or .mpeg), such as those used by some HD camcorders, cannot be played reliably with GStreamer. As such, you may want to remux them in a different container format by using ffmpeg. To convert losslessly to an MPEG4 container, you can use the following command:
ffmpeg -i your_clip.MTS -vcodec copy -acodec copy -sn test.mp4