问题遇到的现象和发生背景
使用RK3568测试USB摄像头，测试过程中报错
遇到的现象和发生背景，请写出第一个错误信息
[root@RK356X:/]# gst-launch-1.0 v4l2src device=/dev/video9 num-buffers=1 !video/
x-raw,format=NV12,width=640,height=480 ! mppjpegenc filesink location=pic4.jpg
Setting pipeline to PAUSED ...
[ 383.092801] uvcvideo: Failed to query (GET_DEF) UVC control 2 on unit 1:
mpp[777]: mpp_rt: NOT found ion allocator
mpp[777-]: m3pp_rt: found drm allocator
(exmpp[777]: mpp_info: mpp version: fb144872 author: Herman Chen 2021-11-04 [hal_task]: Remove unused variable
p. 1).
Pipeline is live and does not need PREROLL ...
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)
ERROR: pipeline doesn't want to preroll.
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...
