IMX Scaler / CSC m2m driver.

[Ian Molton]

On 19/03/15 15:45, Philipp Zabel wrote:
> Hi Ian,

Hi!

> As Nicolas points out, you would have to reduce the amount of copies by
> using DMABUF between the hardware units v4l2videodec
> capture-io-mode=dmabuf ! v4l2convert output-io-mode=dmabuf-import should
> work, output-io-mode=userptr with the current coda driver still throws
> errors. I'll have to investigate that.

I'm not sure copies are the whole story. mmdc shows bus utilisation at
around 1GB/s total, and I've seen FAR higher numbers whe nthe chip is busy.

In any case, I tried your pipeline above on a 1080p video. If it made any
difference at all, its small - I now get 6.5FPS @ 1080p

I'll keep looking at this too. should userptr give a big performance hike?

whats the difference between the various modes? (am I missing some
documentation?) [userptr, dmabuf{,-*} etc.]

-Ian