To synchronize the video camera with a projector earlier we used the VGA signal and Vsync pin on appropriate connector.
It was done in "listening mode", without interfering with computer<->projector interface.
Now we want to use HDMI signal. So, the task - how we can get Vsync from HDMI cable?
VGA cable is connect computer with DLP projector, so no HDCP needed.
Maximum resolution we now use is 1920x1080x60Hz (full frames).
For temporal solution, we start use HDMI splitter. To first HDMI out we connect projector. On second HDMI out we connect HDMI->VGA converter and get Vsync from this VGA. This is work but we want more compact and cheap solution.
What chips we should to use?