I have an application that requires converting an NTSC composite video stream to HDMI. I tried and failed, but ran into some conceptual roadblocks along the way.
I originally designed a circuit that took the composite video source and converted it to BT.656 (using a Texas Instrument TVP5150A). The parallel video output of the BT.656 signal was then connected to an ADV7513. Now, as I understand it, a typical NTSC composite video source has a resolution of 480i. Converting from analog video to HDMI, using the method I just described, won't change that resolution. I'm simply creating HDMI video at 480i resolution. Correct?
I never got anything to display out of the HDMI port. I believe the reason was because I was outputting HDMI with a resolution of 480i and modern displays doesn't support resolutions that low. If that's true, how are NTSC-to-HDMI converters for modern displays typically designed? Does it require a processor in the middle to up-sample the video and increase the resolution? Or do most displays do just fine with HDMI at 480i and I've done something else wrong?