gstreamer caps and v4l2

I know this is slightly off topic for this list, but I hope someone here can help me. I have asked on the gstreamer list, but it's quite often slow/unreliable.

I'm trying to capture video using v4l2src. The problem is that my sensor only delivers bayer RGB and I can't figure out what the caps should be to match. The Linux driver calls the video mode SGRBG10

When I tried these caps
'video/x-raw-bayer,format=(string)grbg,width=2592,height=1944'
it failed with this assertion:
gst_v4l2src_fixate: assertion `G_VALUE_TYPE (v) == GST_TYPE_LIST' failed
So, I thought I might need a more general string:
'video/x-raw-bayer,format=(string){bggr,grbg,gbrg,rggb},width=2592,height=1944'
which now fails with:
gst_value_get_fourcc: assertion `GST_VALUE_HOLDS_FOURCC (value)' failed

Any ideas how I tell v4l2src the details of my sensor?

Thanks

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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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