(Following works are dependent to omap3 camera subsystem driver from OMAPZOOM GIT which is worked by TI and Nokia.)

When we are doing camera job, frame rate checking is being required all the time. (besides when you are not interrested in performance issue)

To be precise, we need to check two seperated sections in kernel space.

Image sensor (or external ISP) <—(*here)—> OMAP3 camera interface <—(**here)—> videobuf module

 

* here : We can check how many frames per sencond are comming from image sensor to OMAP3 camera interface.

** here : We can check how many frames per second are being transfered to user space.

 

To check fps between sensor and OMAP3 camera interface, we should look into omap3_isp_isr which is responding to every interrupts from camera subsystem. Especially we need to focus on HS_VS_IRQ which we can programme detecting sync signal and detecting edge state with SYNC_DETECT bits in ISP_CTRL register. We can make the start of frame countable with detecting VSYNC signal.

So in this case we should check whether the SYNC_DETECT bits are programmed as VS falling or VS rising.

With SYNC_DETECT bits programmed as VS rising or falling, then we could face HS_VS_IRQ with every start of image frame. That makes us available to check how many frames are comming from image sensor to OMAP3 camera interface. Only left job is to check number of HS_VS interrupts happening in a quantitative time.

Now we have to figure out how to check frame rate between OMAP3 camera interface and videobuf module.

=== TBD ===

크리에이티브 커먼즈 라이선스

이 저작물은 크리에이티브 커먼즈 코리아 저작자표시-비영리-변경금지 2.0 대한민국 라이선스에 따라 이용하실 수 있습니다.