$ gst-launch-0.10 -e v4l2src ! video/x-raw-yuv,  width=720, height=487, framerate=30000/1001, format="(fourcc)"UYVY, interlaced=true ! ffmpegcolorspace ! x264enc speed-preset=ultrafast tune=zerolatency bitrate=5000 ! matroskamux ! filesink location=test.mkv
Setting pipeline to PAUSED ...
ERROR: Pipeline doesn't want to pause.
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Could not negotiate format
Additional debug info:
gstbasesrc.c(2830): gst_base_src_start (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
Check your filtered caps, if any
Setting pipeline to NULL ...
Freeing pipeline ...