Use 00_ video_ Decode and render a frame of image (640x480)

[colave]

When I use 00_ video_ Decode and render a frame of image (640x480), with a delay of about 14ms. When I render multiple images in a QT serial port, the delay of the “render” function will increase exponentially with the increase of the number of rendering channels。（2 channel about 30ms， 3channel about 45ms）

[TomNVIDIA]

Hi @colave,

This topic may be in the wrong category. Can you please provide more detail about your issue so that I can find the proper home for this post?

Thanks,
Tom K
Community Manager

[colave]

Thank you@TomK
I repositioned the problem.
I want to display decoded video images in multiple windows，The delay is about 15ms for one channel of video and 30ms for two channels of video.
I found this fucntion:

eglSwapBuffers(egl_display, egl_surface);

It takes a lot of time,

egl_display = eglGetDisplay(x_display)

then I found

x_display = XOpenDisplay(NULL);

In other words, multiple video screen displays use the same x_display .
What bothers me is that will this problem cause delay？
If so, how will I change the parameters of xopendisplay，

I try used
XOpenDisplay(“render0”);
XOpenDisplay(“render1”);
It all caused error, it return nil.

Thanks

[colave]

@colave

Thank you@TomK
I repositioned the problem.
I want to display decoded video images in multiple windows，The delay is about 15ms for one channel of video and 30ms for two channels of video.
I found this fucntion:

eglSwapBuffers(egl_display, egl_surface);

It takes a lot of time,

egl_display = eglGetDisplay(x_display)

then I found

x_display = XOpenDisplay(NULL);

In other words, multiple video screen displays use the same x_display .
What bothers me is that will this problem cause delay？
If so, how will I change the parameters of xopendisplay ，

I try used
XOpenDisplay(“render0”);
XOpenDisplay(“render1”);
It all caused error, it return nil.

Thanks

@TomNVIDIA

Hi @colave,

This topic may be in the wrong category. Can you please provide more detail about your issue so that I can find the proper home for this post?

Thanks,
Tom K
Community Manager

1

[TomNVIDIA]

Are you running a Jetson device?

[colave]

I’m running on Jetson Xavier NX (Jetpack 4.4)

[TomNVIDIA]

Thanks, let me move your topic to the Jetson Xavier NX forum. We have support staff there eager to assist you.

Best regards,
Tom K

[DaneLLL]

Hi,
This is expected on Jetston platforms. For multiple sources, we suggest run each source in individual process. If yo would like to have only single process, the solution is to composite the sources into single plane and then render out. If there are multiple threads calling eglSwapBuffers() simultaneously, the rendering rate will drop.

[colave]

thank you! I’ll try

[colave]

anthoer question is
x86 system will come encounter the same problem？

[DaneLLL]

Hi,
The usecase of Jetson platforms and desktop GPUs are different so the behavior may not be identical. The jetson_multimedia_api is specific to Jetson platforms. For working on x86 PC with desktop GPUs, please try Video Codec SDK.