当我通过guvcview应用打开USB Camera时能够预览到摄像头采集到的图像，但CPU占用率达到了90%-100%；不知原因，希望大家能够帮忙分析分析，需要哪些信息可以在评论区提供。
当我使用qt编译出的qmlvideo应用程序，来打开摄像头时，出现了以下log：
# ./qmlvideo
QML debugging is enabled. Only use this in a safe environment.
** (qmlvideo:1499): CRITICAL **: gst_audio_format_from_string: assertion 'format != NULL' failed
Using mplane plugin for capture
[ 284.950050] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.956124] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.962268] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.968301] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.974362] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.980370] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.986421] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.992425] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 284.998391] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.004390] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.010385] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.016394] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.022380] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.028336] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.034333] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.040404] rkisp1: rkisp_enum_frameintervals Not active sensor
Using mplane plugin for capture
Unable to query the parameter info: QCameraImageProcessingControl::WhiteBalancePreset : "Invalid argument"
Unable to query the parameter info: QCameraImageProcessingControl::ColorTemperature : "Invalid argument"
Unable to query the parameter info: QCameraImageProcessingControl::ContrastAdjustment : "Invalid argument"
Unable to query the parameter info: QCameraImageProcessingControl::SaturationAdjustment : "Invalid argument"
Unable to query the parameter info: QCameraImageProcessingControl::BrightnessAdjustment : "Invalid argument"
Unable to query the parameter info: QCameraImageProcessingControl::SharpeningAdjustment : "Invalid argument"
[ 285.157594] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.165434] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.172210] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.178415] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.184680] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.190922] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.197067] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.203326] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.209365] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.215603] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.221849] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.227895] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.234134] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.240415] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.246545] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.252869] rkisp1: rkisp_enum_frameintervals Not active sensor
[ 285.306591] rkisp1: update sensor info failed -19
CameraBin error: "Could not read from resource."
[ 285.319061] rkisp1: update sensor info failed -19
qml: [qmlvideo] CameraItem.onError error function() { [native code] } errorString Could not read from resource.
qml: [qmlvideo] Content.onFatalError
Using mplane plugin for capture
.................................
CameraBin error: "Device '/dev/video0' is busy"
qml: [qmlvideo] CameraItem.onError error function() { [native code] } errorString Device '/dev/video0' is busy
qml: [qmlvideo] Content.onFatalError
Using mplane plugin for capture