J722SXH01EVM: Does J722S support per-pixel transparency settings?

Hi Kai,

It should be possible to support alpha blending. For a per-pixel alpha, you would have to use one of the color formats that supports an alpha channel, like BRGA (as opposed to a format that does not have any alpha channels like BGR).

Full details of a prior query on J722S for the alpha blending can be found in this thread:  J722SXH01EVM: I would like to display a transparent image using alpha blending on the OSD. 

Regards,

Takuma

Hi Takuma,

Thanks for your reply, I have read the link you provided. To sum up, DSS supports global alpha rendering for overlay layers, but not per-pixel alpha. If we want to achieve per-pixel alpha rendering, we need to choose an image format that supports alpha. Am I understanding correctly?

But for now, we need to use DisplayNode to display images and overlays, and I checked the source code, DisplayNode does not support image formats with alpha channels. What should I do?

Hi Kai, 

Looks like we would need to add a new format for RGBA in the drivers. I am not aware of a patch for J722S, but I can check internally with the broader team. Please expect 1 day for this to allow response from the team in different timezones.

Regards,

Takuma

Hi Kai,

Could you clarify whether you are using Linux for the display driver, or RTOS for the display driver? That is, if vision apps demo is the reference being followed, it will be through the RTOS driver. Whereas, if LInux is being used, the wayland/weston compositor will be in-use.

Regards,

Takuma

ok

RTOS

Hi Kai,

Could you try this patch. It should apply cleanly to 11.2.1. It adds a RGBA to video IO framework.

https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/791/0001_2D00_Add_2D00_RGBA_2D00_format_2D00_support_2D00_in_2D00_DisplayNode.patch

Regards,

Takuma

Okay, I'll check this patch as soon as I can

Hi Kai,

Sounds good.

Regards,

Takuma