Gstreamer pipeline or bug?

Device is a magewell ffplay works flawless after setting the v4l2 width/height
Video input : 0 (Camera 1: ok)
Format Video Capture:
Width/Height : 960/540
Pixel Format : ‘YUYV’
Colorspace : sRGB
Frames per second: 50.000 (50/1)

gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=960,height=520,format=YUY2 ! nvvidconv ! nv3dsink
Setting pipeline to PAUSED …
Pipeline is live and does not need PREROLL …
Setting pipeline to PLAYING …
New clock: GstSystemClock
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data stream error.
Additional debug info:
gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming stopped, reason not-negotiated (-4)
Execution ended after 0:00:00.025437940
Setting pipeline to PAUSED …
Setting pipeline to READY …
Setting pipeline to NULL …

gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw ! nvvidconv ! nv3dsink worked so I was able to look at the verbose and message output and find the problem in the pipeline. It’s now working.

Now the next problem is the RTMP/h264 NVIDIA Accelerated Decode.

The framerate is 50fps and please add it to the pipeline:

$ gst-launch-1.0 v4l2src device=/dev/video0 ! 'video/x-raw,width=960,height=520,format=YUY2,framerate=50/1' ! nvvidconv ! nv3dsink