Framerate detection and refresh rate changing

[imilne]

I don't know how feasible such a request is, because I know gbpvr just hands any video to be played off to DirectShow, but it would be nice if the framerate of the video could be detected (eg, 24, 25, or 30fps), and then the refresh rate of the display changed to match (24p, 50hz, 60hz).

This is already possible with additional software (reclock, powerstrip, etc) but it doesn't work too well, especially if using FSE. You often end up with a black screen if changing the refresh rate after playback has started, if you're even lucky enough for it to detect that it does in fact need to change.

Would would be best (and probably easiest for sub) would be for gbpvr to handle the frame rate detection, then simply hand off to user-configured scripts or executables to perform the refresh rate change (there must be a hundred different ways out there of doing it). As it's gbpvr itself that has asked for the change, it will be able to do whatever reinitialization (or restart of the video) is required to keep the VRM9/FSE display happy.

Personally, I'd keep it simple. Ignoring 23.976/24fps etc technicalities for the moment, the three main rates are 24 (film), 25 (pal), and 30 (ntsc), and if they could be made to work...well...I'd certainly be happy for one :-)

I have noticed some mention of frame rate in the logs from time to time, so hopefully such a feature isn't completely impossible, although I think I've only seen it with live TV rather than with DVDs or AVIs and so on.

[bond007]

I second this, its annoying when playing back NTSC video or HD / Bluray at 24fps, when you are at 50/100Hz, due to your live TV being PAL, so want that video to be smooth.

[BigMoose]

I agree, would be great if it were possible. I can rarely be bothered to manually change it from my PAL live TV setup, but often get annoyed when the thing I'm watching isn't smooth (having forgotten it is a different refresh!).

[imilne]

I second this, its annoying when playing back NTSC video or HD / Bluray at 24fps, when you are at 50/100Hz, due to your live TV being PAL, so want that video to be smooth.

You can simplify things a little bit using Reclock, which will allow you to play 24fps content (Blu-rays, NTSC film DVDs, HD TV Downloads, etc) at 25fps. This means you don't need to adjust your refresh rate to match. Reclock will speed up the video/audio stream by 4% (PAL speedup) so that it plays perfectly at 25fps (50hz).

You really need the PC to do any DD/DTS decoding for this to work though, and then have Reclock output either LPCM to amp, or get it to re-encode the output to DD again with its own encoder. It's not ideal, but it means it's one less refresh rate to have to mess around with.

But if sub could add support directly into gbpvr it would be excellent. I believe (but have never checked) that Media Portal may be able to do this, and even the developer of Reclock has stated that the only way to deal with this problem properly is for the media playback software to handle it, as only the player can stop the playback, set the refresh rate, rebuild the filter graph, resume...

[imilne]

It appears the latest betas of MPC-HC handle this too. I've attached an image that shows the settings dialog for it, and how it asks you to pick a resolution/refresh for each of the likely content frame rates. I guess it just presents a list of the standard Windows timings. I've only run it on my laptop so far, which only allows 60hz anyway.

sub has never said if he plans to include a feature like this () but if he does, perhaps this will give him some ideas...