Frame loss on jetson nano

Autonomous Machines Jetson & Embedded Systems Jetson Nano
#1

Hi, I am new working with this equipment and I would like to ask a question.

I am currently using opencv to test different algorithms, such as object or motion detection and using video sources at different resolutions and different framerate for it.

However, when comparing performance data on my own notebook versus the jetson nano, I have noticed that for videos close to 30 fps there is a frame loss. For the same test video, the total frames analyzed are much lower on the jetson nano than on the notebook.

Does anyone have any idea why this might be happening?

To visualize the total frames I use:

cap.get(cv::CAP_PROP_POS_FRAMES).

I appreciate any information.

#3

Have you enabled the jetson_clocks so the cpu/gpu/emc freq is pulled up to the limit?

1 Like
#4

I must say that I was unaware of the jetson_clocks functionality and I find it very interesting, I set it to get the maximum frequencies as I have found in the documentation.

Before:
SOC family:tegra210 Machine:NVIDIA Jetson Nano Developer Kit
Online CPUs: 0-3
cpu0: Online=1 Governor=schedutil MinFreq=102000 MaxFreq=1479000 CurrentFreq=710400 IdleStates: WFI=1 c7=1
cpu1: Online=1 Governor=schedutil MinFreq=102000 MaxFreq=1479000 CurrentFreq=614400 IdleStates: WFI=1 c7=1
cpu2: Online=1 Governor=schedutil MinFreq=102000 MaxFreq=1479000 CurrentFreq=825600 IdleStates: WFI=1 c7=1
cpu3: Online=1 Governor=schedutil MinFreq=102000 MaxFreq=1479000 CurrentFreq=614400 IdleStates: WFI=1 c7=1
GPU MinFreq=76800000 MaxFreq=921600000 CurrentFreq=76800000
EMC MinFreq=204000000 MaxFreq=1600000000 CurrentFreq=1600000000 FreqOverride=0
Fan: PWM=0
NV Power Mode: MAXN

After:
SOC family:tegra210 Machine:NVIDIA Jetson Nano Developer Kit
Online CPUs: 0-3
cpu0: Online=1 Governor=schedutil MinFreq=1479000 MaxFreq=1479000 CurrentFreq=1479000 IdleStates: WFI=0 c7=0
cpu1: Online=1 Governor=schedutil MinFreq=1479000 MaxFreq=1479000 CurrentFreq=1479000 IdleStates: WFI=0 c7=0
cpu2: Online=1 Governor=schedutil MinFreq=1479000 MaxFreq=1479000 CurrentFreq=1479000 IdleStates: WFI=0 c7=0
cpu3: Online=1 Governor=schedutil MinFreq=1479000 MaxFreq=1479000 CurrentFreq=1479000 IdleStates: WFI=0 c7=0
GPU MinFreq=921600000 MaxFreq=921600000 CurrentFreq=921600000
EMC MinFreq=204000000 MaxFreq=1600000000 CurrentFreq=1600000000 FreqOverride=1
Fan: PWM=0
NV Power Mode: MAXN

Apparently the problem was due to the fact that at some point I re-encoded the videos to work with a Gstreamer pipeline, which caused the frame loss without me noticing it before.

I appreciate your response and sorry for the inconvenience.