Video playback to multiple displays on i.MX8M

[felixradensky]

Hi,

i.MX Linux User's Guide for release L4.9.88_2.0.0 says in section 7.3.1.6 that "Video playback to multiple displays can be supported by a video sink plugin. The video sink for multidisplay mode does not work on i.MX 8 family SoCs"

I'd like to understand if that's a hardware limitation of i.MX8M (LCDIF does not support video playback) or a software limitation.

Thanks.

Felix.

[felixradensky]

We were able to play video on MIPI display driven by LCDIF, so the information in Reference Manual needs correction. Back to my original question, if both HDMI and MIPI+LCDIF support video playback, is it possible to play video to dual display on i.MX8M ?

[felixradensky]

We've manged to play video simultaneously on MIPI+LCDIF and HDMI displays. The following guide was very helpful:

How to use dual display on i.MX8 including 4k decoding - i.MXDev Blog 

[jim_lin]

Hello fradensky‌

I was trying to verify the same feature, could you share the command to run video simultaneously on MIPI+LCDIF and HDMI displays?

[felixradensky]

Hi Jim,

Om i.MX8M EVK you should boot using fsl-imx8mq-evk-dual-display.dtb and run the following commands:

gplay-1.0 --video-sink=kmssink video.mp4 > /dev/null < /dev/null &
gplay-1.0 --video-sink=waylandsink video.mp4 > /dev/null < /dev/null &

Felix

[joanxie]

it should mention software, the chapter 7  multimedia is for gstreamer examples. and for the older bsp user guide, you don't find this information.

[felixradensky]

Hi Joan,

I'm not sure I understand what you're saying.

The i.MX8M reference manual, https://www.nxp.com/docs/en/reference-manual/IMX8MDQLQRM.pdf  says in 13.1.1.1:

The following use cases are supported:
• Dual display: HDMI driven by Display Controller, with video playback support on
HDMI; MIPI driven by LCDIF, without video playback support on MIPI
• Single display: HDMI driven by Display Controller, with video playback support on
HDMI
• Single display: MIPI driven by Display Controller, with video playback support on
MIPI
• Single display: MIPI driven by LCDIF, without video playback support on MIPI.

If my understanding is correct, in Dual display case video can be streamed only to one display, HDMI.

Am I wrong ?

Felix.