Linux/AM5728: Video capture MPU load issue

Marka Reddy

Part Number: AM5728

Tool/software: Linux

We are working with AM5728 EVM. we are capturing video(16bit,y cb cr 4:2:2) from VIP 3A connector which is fed by an external DVI decoder(through jumpers). we are using gstreamer pipe line for video capture with ducatih264enc for compression and storing . we are measering CPU load with htop, mpstat ...etc.

Is there any more reliable way to capture video in AM5728 EVM? Is there any more reliable way to measure cpu load in AM5728 EVM? we are getting a load of 40% for above said video stream. Is this acceptable?

over 8 years ago

0 Margarita Gashova over 8 years ago

TI__Guru* 80190 points

Hello,

Please could you post the pipeline that you are using?

BR
Margarita

0 Margarita Gashova over 8 years ago in reply to Margarita Gashova

TI__Guru* 80190 points

Hello,

I tried this pipeline with the default PSDK4.02 on EVM+camera module:

gst-launch-1.0 v4l2src device=/dev/video1 io-mode=4 ! 'video/x-raw, format=(string)YUY2, width=(int)1280, height=(int)720, framerate=(fraction)30/1' ! vpe num-input-buffers=8 ! queue ! ducatih264enc ! queue ! h264parse ! avimux ! filesink location=1.avi

I am observing this CPU load with top command(check the image).

Hope this helps.

BR
Margarita

0 Marka Reddy over 8 years ago in reply to Margarita Gashova

Expert 1260 points

we are using SDK 4.0 of AM5728 on evm with lcd module .The pipeline is as follows:
gst-launch-1.0 v4l2src device=/dev/video1 ! 'video/x-raw,format=UYVY,height=768,width=1024,framerate=30/1' ! videoconvert ! ducatih264enc ! h264parse ! mp4mux ! filesink location=/home/root/a.mp4 -e

we are observing cpu usage of 40 % on top,htop and mpstat commands.
We need to accommodate 2 more such video sources and hence worried about cpu usage.
Kindly help.

0 Margarita Gashova over 8 years ago in reply to Marka Reddy

TI__Guru* 80190 points

Hello,

It seems normal since you are using videoconvert element.
You could add queue element before the encoder but the cpu load will almost the same.

BR
Margarita

0 Margarita Gashova over 8 years ago in reply to Margarita Gashova

TI__Guru* 80190 points

Hello,

I tried on my side the same pipeline but I replaced vpe with videoconvert element:
gst-launch-1.0 v4l2src device=/dev/video1 io-mode=4 ! 'video/x-raw, format=(string)YUY2, width=(int)1280, height=(int)720, framerate=(fraction)30/1' ! videoconvert ! queue ! ducatih264enc ! queue ! h264parse ! avimux ! filesink location=1.avi

I observed CPU load >90%.

BR
Margarita

0 Marka Reddy over 8 years ago in reply to Margarita Gashova

Expert 1260 points

Thanks for the inputs.
Further,can we conclude that vpe can reduce cpu load considerably ? AM5728 is a dual core system . so effectively cpu load is >45%?
what is the difference between cpu load and cpu utilization?

0 Margarita Gashova over 8 years ago in reply to Marka Reddy

TI__Guru* 80190 points

Hello,

Marka Reddy said:
Further,can we conclude that vpe can reduce cpu load considerably

Please check this user guide:

http://processors.wiki.ti.com/index.php/Linux_Core_VPE_User's_Guide

One note:
gstreamer vpe element supports NV12, YUY2, YUYV formats on the input and output.

Marka Reddy said:
what is the difference between cpu load and cpu utilization?

https://stackoverflow.com/questions/30831230/difference-between-cpu-usage-and-cpu-utilization

BR
Margarita

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Linux/AM5728: Video capture MPU load issue