Reply to thread

Message

<blockquote data-quote="Owlsroost" data-source="post: 608472" data-attributes="member: 83973">Given the problems it's creating, I might revert to using the Windows reported value for now (but I'd love to know why the calculated values are so inaccuarate on your system - the timing polling loop runs at 'critical' thread priority, so is Win7 taking bigger chunks of time away from the thread so it misses a vsync sometimes ?)Concerning the stats jitter etc - I've found that positioning the 'start of paint' time relative to display vsync can be critical - on my system (1080p display) it targets approx scanline 250 for start-of-paint, and paint finishes at approx line 500. Sometimes the end-of-paint point will change to just after line 0 i.e. something is delaying the return from PresentImage() until after the next vsync. I've no idea why this happens, but I assume there's more raster related synchronisation happening further down the render pipeline....If you want to move this discussion to a more suitable place that's OK with me, but it would be nice to move the recent dshowhelper discussion posts as well so it's all in one thread.Tony</blockquote>

[QUOTE="Owlsroost, post: 608472, member: 83973"] Given the problems it's creating, I might revert to using the Windows reported value for now (but I'd love to know why the calculated values are so inaccuarate on your system - the timing polling loop runs at 'critical' thread priority, so is Win7 taking bigger chunks of time away from the thread so it misses a vsync sometimes ?) Concerning the stats jitter etc - I've found that positioning the 'start of paint' time relative to display vsync can be critical - on my system (1080p display) it targets approx scanline 250 for start-of-paint, and paint finishes at approx line 500. Sometimes the end-of-paint point will change to just after line 0 i.e. something is delaying the return from PresentImage() until after the next vsync. I've no idea why this happens, but I assume there's more raster related synchronisation happening further down the render pipeline.... If you want to move this discussion to a more suitable place that's OK with me, but it would be nice to move the recent dshowhelper discussion posts as well so it's all in one thread. Tony [/QUOTE]

Verification