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  1. I am using a dual monitor arrangement. Both monitors are set to HD (1920x1080). I am using a script to launch MPC to play selected HD videos fullscreen to monitor 2 (which is actually a 65" smartTV - for presentations to a group of people). Monitor 1 is effectively my operator's console. Both monitors are normally set to run at 50Hz (the videos to be played are all recorded at 25Hz - so using 50Hz should minmise the chance of beating impacting the smooth flow of the videos).

    It all works, with one "but". When MPC launches/ends something happens to the signal to monitor 2. My best guess is either the signal dies completely for a short period, or maybe the mode switches (perhaps a different frequency?). I have tried with a couple of models of TV - with one (a cheap Cello model) the effect is a slight "jump" to the display - the other (a Sony Bravia) cuts out completely for a couple of seconds (no prizes for guessing which one I will actually use).

    I have tried changing the monitor frequency to 59Hz and 60Hz - but this doesn't appear to change the symptoms in any noticable way.

    The MPC option "use autochange fullscreen monitor mode" is NOT checked (although checking it makes no difference - I have noticed none of the options is 50Hz).

    I'd really like to eliminate this effect completely, as having this happen on a large screen is distracting & irritating, and I'd prefer not to annoy my audience with it.

    Any suggestions?
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  2. Under the Play/After Playback menu, the option to shut down monitors isn't checked?

    I can't duplicate the problem and my monitor and TV run at different refresh rates. I'm not opening MPC-HC with a script, but when it's set to launch video in fullscreen mode and with the TV as the fullscreen monitor, and set to exit fullscreen mode after playback, with Windows Explorer open on the monitor (not the TV) when I double click on a file to open it, the video opens fullscreen on the TV and when it's finished playing the MPC-HC window appears on the monitor. The TV doesn't cut out at all.
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  3. Thanks for the suggestion, but that option is not checked.

    When I use smaller monitors I don't get the problem. It only occurs on the big "smart" TVs. My guess is it is something to do with economy modes - which is why I wonder if the signal drops for a very short time.
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  4. Member DB83's Avatar
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    AFAIK monitor refresh rate has zilch to do with the frame rate of your video. In fact the higher the refresh rate should be better.

    What may be important here is the length of cable from the source to the 2nd display.

    Of course I would imagine a momentary break in the flow of info from source to monitor could result in a picture disturbance.

    Maybe you can overcome that by creating a playlist so there is a smooth transition from one video to another.
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  5. Originally Posted by DB83 View Post
    AFAIK monitor refresh rate has zilch to do with the frame rate of your video. In fact the higher the refresh rate should be better.
    Playing 25p material on a 50p display is noticeably smoother than a 60p display. With a 60p display four out of five source frames are displayed for the duration of two TV frames, with every 5th frame displayed for the duration of three TV frames (ie, 5 source frames becomes 6 TV frames, 50 becomes 60). This leads to 10 little jerks every second. On a 50p display every source frame is displayed for two TV frames so you don't get the jerks.
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  6. Can you post the script you are using?
    Does it also happen without the script? Or do you need the script for that specific usage?
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  7. Tried a short cable (2m) but made no difference. I need breaks between the videos, so I can't flow one into the other.

    Command line from batch file:
    "C:\Program Files\MPC-HC\mpc-hc64.exe" /play /close /fullscreen /monitor 2 D:\avfiles\%1
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  8. Member DB83's Avatar
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    I am no expert with command line processing ( we have a resident 'cat' who lives by this ) but something looks wrong.

    Why is there a close command after play but before the monitor is selected and the video which in dragged in to the batch ?
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  9. The help info says "close" means "close after playback" so that shouldn't be the problem.
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  10. Member DB83's Avatar
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    @jagabo

    I always bow to your better knowledge of these things. Yet in PAL land, where the majority of my video is PAL I simply do not see these 'jerks'. I just wonder whether it is more a consequence of 'conversion' for display on NTSC equipment rather than the refresh rate itself.
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  11. Originally Posted by DB83 View Post
    @jagabo

    I always bow to your better knowledge of these things. Yet in PAL land, where the majority of my video is PAL I simply do not see these 'jerks'. I just wonder whether it is more a consequence of 'conversion' for display on NTSC equipment rather than the refresh rate itself.
    Most PAL gear seems to be NTSC based with PAL abilities tacked on, so they support 50Hz and 60Hz refresh rates (the players and TVs here all default to 60Hz when they're turned on and they display their menus at 60Hz). When you play a PAL disc in a Bluray player connected via HDMI, the player should automatically switch the TV to 50Hz. Plasmas generally refresh the screen at 75Hz instead, even though the signal is 50Hz, as a 50Hz refresh rate would "flicker". At 75Hz, each 25fps frame can display for exactly 3 refreshes.
    One of the Bluray players here only switches the TV to 50Hz when playing discs, while the other is clever enough to do it when playing 25fps MKVs via it's USB input.

    I'm pretty sure my TV always refreshes at 60Hz when the built-in USB media player is used, regardless of the frame rate, but switching to the built-in media player is the one time it doesn't briefly display the refresh rate on the screen.
    Last edited by hello_hello; 31st Aug 2018 at 12:28.
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  12. An easy way to see judder when playing a 50 fps file on a 60Hz display:
    1.) Look in driver menu or windows monitor settings what refresh rate it is set to -> We need 60 Hz.
    2.) Open the 50 fps file in MPC-HC or my personal favourite for almost six years now -> MPC-BE and press Ctrl + J and look at the graph in the lower right corner
    3.) for comparison open a 60.000 fps file for 60 Hz Mode http://bbb3d.renderfarming.net/download.html
    4.) There is the 59 Hz Mode for real 59.94 fps and a 60 Hz for the exact but very rare 60.000 fps files like Big Buck bunny sample file.

    I only used progressive 50 fps / 59.94 fps / 60 fps. Interlaced content should be deinterlaced and then you have the exact same case -> one frame for one field, the only real way of deinterlacing, so in this case to look at judder not necessary to look at.
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  13. I have solved my original problem - but in a rather drastic way. I have written my own application based on Microsoft's SimplePlay example (see: https://docs.microsoft.com/en-us/windows/desktop/medfound/simpleplay-sample) modified to use a borderless (& menu-less & everything-else-less) window exactly overlaying the second monitor. This means I lose one of the issues associated with launching a 3rd-party player for every video (the momentary display of the window before going fullscreen). This solves things on my Cello TV.

    However the Sony still cuts out the display momentarily approx. 300ms after the start & end of each video play. I can work round this by making the first 500ms of every video a blank screen, and waiting 500ms after the end of each video before displaying anything else. Having done this the problem is completely masked on either TV I have.

    If anyone is interested, I found it very easy to modify SimplePlay to display multiple videos on demand, but once I had played a video I could never manage to bitblat a still image to the same window - so I solved that by placing still images in a seperate "on top" window, which I destroyed at the start of each video & recreated at the end. (I'm not saying you can't put both video and still images in the same window - just that I didn't figure out how & launching a separate window was too easy a solution for my lazy brain).

    Anyway - my specific problem is solved: I can play videos whenever I want, with still images between, completely filling the second monitor, with no annoying flicker or cutouts at the start & end of videos.
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