https://www.raspberrypi.org/forums/viewtopic.php?p=1730991#p1730991
> > ah, so that part would still be waiting on a proper ISP driver in linux
> Broadcom IP - there won't be a native Linux driver for it.

https://android.googlesource.com/kernel/bcm/+/android-bcm-tetra-3.10-kitkat-wear/drivers/char/broadcom/isp2/isp2.c
> You've got a very remote shot with https://android.googlesource.com/kernel ... sp2/isp2.c but its largely just allowing userspace to map the registers to be poked and handling the interrupts.
> There are a couple of revisions of the isp hardware, and I don't recall if Java and Rhea had the cut-down versions or the full ones.


https://www.raspberrypi.org/forums/viewtopic.php?p=1765429#p1765429
> We normally reckon on around 130MPix/s through the ISP. 1280x800@120fps is 122.8MPix/s, and you're trying to do that twice!
> I don't think the ISP has been accurately benchmarked for a long time. Theory is it can handle one pixel per clock cycle, but that's limited both sides of any scaling. It also works in tiles with overlaps, so full throughput depends on exactly how many tiles are required.


https://www.raspberrypi.org/forums/viewtopic.php?p=1832607#p1832607
details on which v4l nodes do what

https://www.raspberrypi.org/forums/viewtopic.php?p=1832607#p1832607
> media-ctl --print-dot /dev/media2 > isp.dot
> dot -Tpng isp.dot > isp.png