GstQtOverlay plugin performance on Xavier NX

For testing purposes, take into account the following points:

• Maximum performance mode enabled: all cores, and Jetson clocks enabled
• Jetpack 4.4 (4.2.1 or earlier is not recommended)
• Base installation
• The GstQtOverlay is surrounded by queues to measure the actual capability of GstQtOverlay

For measuring and contrasting the performances with and without NVMM support, we used the following pipelines:

NVMM:

gst-launch-1.0 videotestsrc pattern=black ! 'video/x-raw, width=1920, height=1080' ! queue ! nvvidconv ! queue ! 'video/x-raw(memory:NVMM)' ! qtoverlay qml=gst-libs/gst/qt/main.qml ! perf ! queue ! nvvidconv ! 'video/x-raw' ! fakesink sync=false

No NVMM

gst-launch-1.0 videotestsrc pattern=black ! 'video/x-raw, width=1920, height=1080' ! queue ! qtoverlay qml=gst-libs/gst/qt/main.qml ! perf ! queue ! fakesink sync=false

The results obtained:

Measurement	Jetson NX
No NVMM	190 fps
NVMM	265 fps

With the addition of native UYVY and NV12 support for NVMM memory, we measured the performance for each format between using nvvidconv or the native support. The following pipelines were used:

NVMM using nvvidconv:

gst-launch-1.0 videotestsrc pattern=black ! 'video/x-raw, width=1920, height=1080, format=RGBA' ! queue ! nvvidconv ! queue ! 'video/x-raw(memory:NVMM), format=RGBA' ! qtoverlay qml=gst-libs/gst/qt/main.qml ! perf ! queue ! nvvidconv ! 'video/x-raw' ! fakesink sync=false

NVMM with native UYVY and NV12 support:

gst-launch-1.0 videotestsrc pattern=black ! 'video/x-raw, width=1920, height=1080, format=NV12' ! queue ! nvvidconv ! queue ! 'video/x-raw(memory:NVMM), format=NV12' ! qtoverlay qml=gst-libs/gst/qt/main.qml ! perf ! queue ! nvvidconv ! 'video/x-raw' ! fakesink sync=false

The results obtained:

Measurement	RGBA	UYVY	NV12
NVMM with nvvidconv	227 fps	200 fps	177 fps
NVMM with native formats	227 fps	172 fps	177 fps

CPU usage

Take the following pipelines as reference:

No NVMM

gst-launch-1.0 videotestsrc is-live=true ! 'video/x-raw, width=1920, height=1080'  ! qtoverlay qml=gst-libs/gst/qt/main.qml ! 'video/x-raw, width=1920, height=1080' ! fakesink

NVMM:

gst-launch-1.0 videotestsrc is-live=true ! 'video/x-raw, width=1920, height=1080' ! nvvidconv ! 'video/x-raw(memory:NVMM), width=1920, height=1080' ! qtoverlay qml=gst-libs/gst/qt/main.qml ! nvvidconv ! 'video/x-raw, width=1920, height=1080'  ! fakesink sync=false

Results

Measurement	No NVMM	NVMM
GstQtOverlay	16.5%	7.3%
Rest of pipeline	14%	27.8%
Total	30.5%	35.1%

The total consumption of the pipeline is higher in the NVMM case since there are more elements. The GstQtOverlay consumes less CPU in NVMM mode.