About the details & difference EVIS2 and EVIS1 [i.MX8MP + gtec-demo-framework]

[HME15769]

Hello NXP.

I'm trying to build the stereo demo from gtec-demo-framework with OpenVX on i.MX8MP board.
But this demo output a segmentation fault. And after I referred to this post, I got the wrong disparity image from stereo demo.
https://community.nxp.com/t5/i-MX-Processors/i-MX-8MP-OpenVX-Stereo-demo-crash-in-gtec-demo-framewor...

I found the issue that this demo isn't supported the i.MX8MP. and only supported the i.MX8MQ.
The repo's committer said that the issue occured by the difference EVIS1 and EVIS2.
https://github.com/NXPmicro/gtec-demo-framework/issues/5#issuecomment-944006997

Could you tell me about the EVIS2 API, the detailed difference EVIS1 and EVIS2, and whether it is possible to build the demo with EVIS2 ?
I don't know any details beyond links below.
https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/OpenVX-Vision-Image-Extension-API-Introd...
https://www.nxp.com/docs/en/user-guide/I.MX_GRAPHICS_USERS_GUIDE.pdf

Thanks.

[HME15769 · Accepted solution]

There was an improper instruction and codes  and unnecessary process in the OpenCL kernel function, so I fixed it and got it working.
The processing time is about 1 second and the accuracy is not good, so it is better to use OpenCV StereoBM class.

I found the OpenVX documentation from Rockchips Corp most helpful.

[HME15769]

Hi, @joanxie 
sorry for late reply.

the NPU of imx8mp doesn't support EVIS1. It only supports EVIS2

I know that.

The Github issus has been hidden and the README still states that it can be run on the i.MX8 series.

Why not state that it only runs on i.MX 8QM?

"https://github.com/nxp-imx/gtec-demo-framework/tree/master/DemoApps/OpenVX/Stereo"

[joanxie]

the NPU of imx8mp doesn't support EVIS1. It only supports EVIS2

maybe you can refer to the document as below

"https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-to-use-OpenVX-extension-for-NPU-GPU-..."