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  1. Hi, I have this 60Hz fixed refresh rate LED monitor (the laptop screen). And I am playing videos of usual frame rate of 23, 23.976, 24, 25, 30 etc. I am using PotPlayer+MadVR+LAV+Haali media splitter. The question is, when I play videos, the source frame rate is output as more i.e MadVR output it to something like 27, 33, 44...upto display refresh rate. Now, should I be worried of missing scenes from movie due to more FPS being displayed or in other words less playback time? I don't see difference though cuz I don't remember each and every scene and there is no visible difference in time skip. There is however frame drops, no wonder. The playback is smooth except sometimes there is jitter/judder in some videos (bad files may be)

    MadVr is in exclusive screen mode (They say its better and stable although switching from windowed to exclusive freezes the video sometimes). In windowed mode, the FPS is near to the source FPS or less or greater sometimes (in AVI files).

    I've heard about this re-clock software but I guess it won't work in 60Hz monitor as there is no other supporting refresh rate for it.
    I have no idea about this FPS changes by MadVR and its effect in movie playback. Should the source and display frame rate be equal?

    [img]framerate.jpg[/img]

    Thanks in advance for your suggestions!
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  2. Member
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    Which version of madVR are you using? The latest version is v0.86.0. And if you're using LAV, do you really need Haali media splitter?

    As an alternative, try mpc-hc lite + madvr + lav, hit ctrl+j when you play something with mpc-hc and see what the debug OSD says.

    This might also help you get smoother playback; set everything to bilinear, see how your laptop performs, then gradually change the chroma / image scaling algorithms.

    To answer your question "Should the source and display frame rate be equal?", well, no. There are three rates to consider when using madVR.

    Source frame rate is just that, it will depend on the file you're playing (eg 24p, 25p, 50i, 60i and so on)

    Display rate is the refresh rate that your display is set at, in your case, 60 hz, but it's never exactly 60, there is always some deviation, it might be 60.0001, etc.

    The third rate, which I don't know if it's displayed by PotPlayer, is the composition rate, is how many frames per second madVR constructs from your source file by using pulldown. As an example, take a 29.97 fps file and a 59.94 Hz display rate. As I mentioned before, the display will not be exactly 59.94 Hz. So madVR will compose its output at 59.94 fps and will repeat frames at intervals which it determines to match your display rate.

    See the capture below for how it looks inside MPC-HC.

    Last edited by Island_Dweller; 22nd Feb 2013 at 16:03.
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  3. Originally Posted by Island_Dweller View Post
    Which version of madVR are you using? The latest version is v0.86.0. And if you're using LAV, do you really need Haali media splitter?
    I use MadVR 0.86.1. Haali is for splitting mkv files only.

    This might also help you get smoother playback; set everything to bilinear, see how your laptop performs, then gradually change the chroma / image scaling algorithms.
    I really don't like bilinear even though my laptop(general use core i3; 2nd generation) is not high end, I use Chroma= bilinear 75, Luma=Lancroz 3 tap or softcubic50. I know when I use bilinear there are fewer frame drops but the picture quality is not that good so it is ok if there are few frame drops. :/
    Playback is smooth cuz most of the videos are below 1080p.

    To answer your question "Should the source and display frame rate be equal?", well, no. There are three rates to consider when using madVR.

    Source frame rate is just that, it will depend on the file you're playing (eg 24p, 25p, 50i, 60i and so on)

    Display rate is the refresh rate that your display is set at, in your case, 60 hz, but it's never exactly 60, there is always some deviation, it might be 60.0001, etc.

    The third rate, which I don't know if it's displayed by PotPlayer, is the composition rate, is how many frames per second madVR constructs from your source file by using pulldown. As an example, take a 29.97 fps file and a 59.94 Hz display rate. As I mentioned before, the display will not be exactly 59.94 Hz. So madVR will compose its output at 59.94 fps and will repeat frames at intervals which it determines to match your display rate.
    Exactly, this is the answer to my question I suppose. MadVR OSD displays the refresh rate and composition rate in both potplayer and mpc.
    Refresh rate = 59.91Hz
    Composition rate = 60 Hz
    So, I don't know what is pulldown but when you said frames are repeated, does that mean I get to see scenes again or its just to trick the eye? And so your answer means I should not worry about the FPS conversion by MadVR?
    And btw, I noticed the difference in frames count from the '#Frames' in Potplayer OSD. It turned out that the playback FPS is nearly equal to source FPS with 2 or 3 frames in addition. So, its MadVR who is doing something to match the refresh rate of the screen.

    Note: I am not using MadVR's smooth motion (kind of puts heavy load on PC)

    Now, I am left with frame drop problem which I guess will be solved if I set bilinear algorithm, which of course I don't like!

    If that's the final solution to my query then Thank you. It did helped me to stop worrying and finally had a little peace
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  4. Here is the screenshot of the MadVR OSD. Horrible frame drops, right? I'll never understand why such frame drops even if the PC usage doesn't go up by 25%. It should be able to decode, render or whatever on time by applying all the power it has.
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    LAV splitter supports mkv files just fine, that's why I asked about Haali.

    Well, if your source is 24fps and your laptop can only do 60 Hz, then madVR will have to apply 2:3 pulldown. Pulldown, in this case, is simply repeating frames in a fixed pattern to match source frame rate to display rate. For example two frames AB will become AABBB.

    The frame drops are probably a result of the onboard GPU. When you open LAV Video configuration, does it list "Intel Quicksync" as available under hardware decoder?

    I also see that you're upscaling from 1280x720 to 1366x768, yes? If you don't mind black borders when playing fullscreen, play it back at the original resolution, this way you'll only be upscaling chroma instead of upscaling chroma + image.

    There's also an option inside madVR settings > rendering > general settings. Try "use a separate device for representation" on or off, see if this decreases rendering times (it's listed under average stats and max stats in your screenshot).
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  6. Originally Posted by pearlblack15 View Post
    should I be worried of missing scenes from movie due to more FPS being displayed or in other words less playback time?
    No. Individual frames are repeated to increase the number of frames. For example, 24 Hz material is increased to 60 Hz by repeating half the frames 2x and half the frames 3x, alternating between the two (ie, 2/60 and 3/60 second). So on average each frame is displayed 2.5x -- 24 * 2.5 = 60. This creates a "judder" which can be seen, especially, on smooth panning shots. But if you live in an NTSC country you're used to this judder -- every movie you've ever watched on TV has it.

    See the video in this post for an example of 3:2 repeat judder:
    https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30-...=1#post1888926
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  7. Originally Posted by Island_Dweller View Post
    LAV splitter supports mkv files just fine, that's why I asked about Haali.
    Haali gives an impression that its faster than LAV at present, while skipping. I hope we'll eventually migrate to LAV later.

    The frame drops are probably a result of the onboard GPU. When you open LAV Video configuration, does it list "Intel Quicksync" as available under hardware decoder?
    Yes, it does and I am presently using Quicksync for HW acceleration and HW decoding.

    I also see that you're upscaling from 1280x720 to 1366x768, yes? If you don't mind black borders when playing fullscreen, play it back at the original resolution, this way you'll only be upscaling chroma instead of upscaling chroma + image.
    Yes, the madVR OSD says that. I don't mind black borders. But I checked the Potplayer settings. Aspect ratio is set to 'keep aspect ratio' and 'do nothing' and output aspect ratio is set to 'monitor'. Will changing that play the video to its source resolution? But some videos come with black borders while others don't and they play with or without it depending on the source. But lets keep this aside. Its ok if it put some load on the CPU. I just want to confirm that intel HD 3000 is not good enough What annoys me sometimes is that its usage is not beyond 50% which gives an impression that it should be capable of doing the calculations without glitch at low/normal settings but it doesn't. Oh! Intel!
    Anyway, I'd like to know how we can tell MadVR to play at original resolution so I can check any difference in quality/performance!

    And did you see the first screenshot posted? The OSD reports output as 2048x720 from 1280x720. What's that?

    There's also an option inside madVR settings > rendering > general settings. Try "use a separate device for representation" on or off, see if this decreases rendering times (it's listed under average stats and max stats in your screenshot).
    Thanks! Turning the feature ON decreases rendering time by around 8ms or so under average stats. Does it hand over the processing to CPU from GPU, in this case ? I don't see any change cuz the usage fluctuates!
    Last edited by pearlblack15; 24th Feb 2013 at 08:37.
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  8. And Thanks both Island_Dweller and jagabo, I now have pretty much got the idea of 3:2 pulldown and why Potplayer OSD reports FPS conversion to near 60 Hz. This is no longer a problem to worry about.
    Thanks again
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    Originally Posted by pearlblack15 View Post
    And did you see the first screenshot posted? The OSD reports output as 2048x720 from 1280x720. What's that?
    That is normal behavior of LAV video decoder. I get the same thing here, even with 1080p, it shows NV12 2048x1080. Nothing to worry about.

    Originally Posted by pearlblack15 View Post
    Thanks! Turning the feature ON decreases rendering time by around 8ms or so under average stats. Does it hand over the processing to CPU from GPU, in this case ? I don't see any change cuz the usage fluctuates!
    I'm not sure, madVR uses GPU as much as it can and since you're using Quicksync, most of the calculations are done inside GPU. Even with 1080p24 with Jinc 3 taps and anti-ringing activated for chroma, I see less than 20% CPU usage on my quad core q6600.
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  10. ^^ Ok thank you. One last question: If the usage of the processor (CPU+GPU) is always at 15-25-50 (max) % whenever I watch SD or HD materials with low-medium settings, will it decrease the life expectancy or performance too soon? I had an AMD machine earlier and it was put to heavy processing always. In the end the fan started to make too much noise, occasional hangs and restarts. It could be due to HDD problem or OS but there is just a little fear of rough use of the system. Although this sounds funny cuz we buy pretty powerful systems but we are afraid or get worried when it is put to heavy load. We don't want it to work hard
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    Well, it's usually the high temperatures that I worry about. I've had my current processor for 5 years and for the first year I was using Intel's stock cooler. While encoding video or using Photoshop, temperatures would rise dramatically, up to 90° C. This would cause shutdowns and all kinds of problems. The fix was to get a better CPU cooler and now it never goes above 50° C.
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  12. Well, it's usually the high temperatures that I worry about
    Same here.. it goes up by 80° C while encoding and complex processing and 1080p Playback. This is obvious given the fact that its a mobile processor even if its core i3 2nd gen. Other times its normal 40° C or just near 60° C. I've got to keep an eye on temp rise!

    The fix was to get a better CPU cooler and now it never goes above 50° C.
    That's great. Unfortunately there is not much choice I have.
    -------------------------------------------------------------------
    Anyway, thanks for all the help.
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