v4l2src ! v4l2h264enc ! filesink Dont work on IMX6 board

[_dmp]

I have board Fscale IMX6, Mesa 18.1.5, Etnaviv , GStreamer 1.14.4, Qt5.9
Kernel: Linux 4.19.45
No Xorg, no Wayland. Only EGLFS.

My board have no ipu and  gst-imx components activated. So I have no
hardware image processing unit and have no gst components for hardware color
space converting.  I choice glcolorconvert but it dont work as need... 
When reconciling v4l2src and v4l2h264enc, I convert the color space from
YUY2 to the format that supports IMX6 VPU - NV12. During operation, a CAPS
negotiation error occurs. As well as an error in the activation of the
GL-transform. Below is a run log.

https://pastebin.com/raw/YFSWbSYV

I try run pipeline like this:

l_pipelineReadStr = g_strdup_printf( "v4l2src  device=/dev/webcam
num-buffers=30 ! "
              " capsfilter caps=\"video/x-raw, format=YUY2,
pixel-aspect-ratio=1/1, framerate=30/1, width=%1$d, height=%2$d\"
name=videoconvertcapsfilter ! "
              " glupload ! "
              " glcolorconvert name=glcolorconvert_to_qmlglsink_color !
video/x-raw(memory:GLMemory), format=NV12 !  "
              " gldownload ! "
              " queue ! "
              " v4l2h264enc output-io-mode=dmabuf
extra-controls=\"controls,h264_level=9,video_bitrate=200000;\" ! "
              " h264parse ! mp4mux ! filesink
location=/ext/ssd2/capture.mp4",
                                                 320, 240 );



--
Sent from: http://gstreamer-devel.966125.n4.nabble.com/