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Taylor: Avoiding Jitter in Composited Frame Display

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 2, 2012 11:11 UTC (Sun) by alankila (subscriber, #47141)
In reply to: Taylor: Avoiding Jitter in Composited Frame Display by Jonno
Parent article: Taylor: Avoiding Jitter in Composited Frame Display

If we have 100 Hz full-field replacement rate (that is, 100 real pictures per second to both eyes), then I stop worrying about this kind of jitter because I believe that humans in general aren't truly sensitive to jitter less than about 10 ms. However, rather than raising the bandwidth cost, power usage, and wasted memory bandwidth, it might make sense to just give software a toggle that allows it to tell the display the timestamp it should be begin (or be in middle of) transition to the new frame.

If you think about LCDs as a system, they would be ideal for this: they are displaying one picture using the current frame, and the computer uploads the new frame to them at some rate, which can be decoupled from the frame switch rate as long as the data is transferred before the frame switch is requested. Normally the switch is triggered synchronously over the entire display area when the new frame is fully transferred, but nothing would prevent there being a delay after the frame has been transferred where it waits for a specific timestamp.


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