Software ISP on the IMX8Mini

[VishnuSidda]

We are using a IMX8mini, previously we used to work with imx8mplus which has the inbuilt hardware ISP, but the IMX8Mini does't have the hardware ISP support. 

What are the options do we have to do the debayering, 3A, gamma and other ISP functionalities. In my exploration, we found NXP Soft ISP not available on the imx8mini, libcamera is not officially supported on the imx8mini and we have no experience in integrating the libcamera and their pipeline handlers stuff.

One more thing, in imx8mplus we routed video through the ISP or there is a provision to route video through ISI in capture mode. How does that happens in the imx8mini, no vvcam stack stuff?
By the way, our camera doesnt have inbuilt ISP, we have to perform the software ISP on the processor itself.

I hope some of you guys know this.

Thanks and regrads

S Vishnu  

[kieranbingham]

libcamera has a GPU implementation of the SoftISP which could be used on the i.MX8MM but may not give high throughput as I don't think the GPU on the i.MX8MM is very large. It functions, but not at high framerates, so it likely depends on what your requirements are.

[Chavira · Accepted solution]

HI @VishnuSidda,

On the i.MX8M Mini, the camera data goes straight from the sensor to memory using CSI + ISI. ISI is not an ISP; it only moves images around and can resize them a bit. There is no stage where RAW images can be processed like on i.MX8M Plus, and there is no vvcam or Soft ISP stack available.

Libcamera is supported only in a very limited way on i.MX8M Mini. It works only with cameras that already have an ISP inside the sensor (so‑called “smart cameras”). Libcamera on i.MX8MM does not add ISP features; it just helps manage capture. It cannot replace a missing ISP.

Doing a full software ISP on the CPU is technically possible but not recommended due to high CPU load, power consumption, and complexity, and NXP does not provide or support such a solution on i.MX8M Mini.

In i.MX8M Mini is capture only for cameras. If ISP features are required, they must be handled outside the SoC.

Best Regards,

Chavira