i.MX8 MP ISP performance for dual camera system

[holgerweber]

I want to build a system, bases on i.MX8 MPlus to stream to 4k@30fps videos with h2654.
There are two cameras 4k connected to the two CSI channels. I selected the M Plus because it has an ISP and I thought that this can handle the whole debayering and correction without consuming the CPU.

I checked the "i.MX 8M Plus Applications Processor Reference Manual" (IMX8MPRM) and in Chapter 13 on page 5157 i found:
"When two ISPs are used simultaneously, each supports:
• maximum resolution up to 1080p (1936x1188)".

I was surprised that, as soon as I use a second camera the ISP can only process images with a max. resolution of 1080p. So for my use case it is not possible to stream two 4k videos.

Any ideas how to solve this with an imx8MP?

[joanxie]

what camera input format do you need? if you don't use raw data, you can use ISI for the second camera

[holgerweber]

Hi,

we have RAW format. I also saw that there is a soft ISP which can do debayering etc.
Any idea how many frames it can handle at 4k?

[joanxie]

can reach 30fps

[holgerweber]

That sounds good.

Is there a table overview where I can find the performance for different resolutions?

eg.

4k@30FPS
FHD@200FPS
SD@2000FPS

[joanxie]

if you mean ISI, one ISI can reach 500M max, you can calculate for your camera, we don't have such table, and we don't test such higher frame rate with lower resolution, on theory, imx8mp can support this if they don't over 500M

[holgerweber]

I don't mean the ISI because it can't handle raw images. I mean the softISP, on which you answered before.

[joanxie]

since imx8mp has built-in ISP, we don't have any softISP test result on imx8mp, but you can refer to the result based on imx8mq

High application performance (OpenCL: ~28 fps, 1080p, OpenVX: ~39fps, 1080p).