My guide to elminating juddering/stuttering play back (plus an upscale guide!) (1 Viewer)

[doveman]

The Spyder is a "low-cost" consumer option. They vary great in quality. But they are better than nothing!

I'm not so sure about that. I was planning to get a Spyder but then I read reports about how the factory calibration was so bad that many of the units need calibrating against a known good unit before they're usable (otherwise you're just calibrating your screen to some arbitary, wrong, target). I'd like to get the EyeOne Display 3 but they're quite a bit more expensive so I think I'll just have to do without for now I've done a reasonable job getting the gamma, brightness, contrast and colours looking OK without (it helps that I can turn off individual colour guns on my TV) but I know once I'm able to properly calibrate it I'll realise how off it currently is.

Regarding setting deinterlacing in the profiles, is that not unnecessary considering the GPU will do that (on the GPU so reducing the CPU load)? I use ATI which I've set to use Vector Adaptive deinterlacing in CCC.

Regarding the display output setting in the GPU control panel, I think you have to be careful if you use the PC to play games as well as watch video, in which case you probably need to set it to display full 0-255 RGB and then set your video settings/profiles to make sure the video displays correctly. I guess the Control Panel Video Colour "Dynamic Range" setting you mentioned should only affect video though, I'm thinking more of the "Desktop Color Settings". With the way my ATI is connected to my monitor (DVI) I only get a Dynamic Range setting under Video Colour anyway, but I think with other types of connection/TV some additional options appear that could affect non-video stuff.

 

[Scythe42]

The Eye One is very good for calibrating displays. I can highly recommend it.

You can't use hardware de-interlacing and then apply ffdshow filter afterwards.

Before doing scaling and other stuff the picture has to be de-intetrlaced. So either the codec you use does it, meaning it uses the GPU for it, or if the codec can't do it then ffdshow has do to it by software, so it can apply its post-processing properly.

Using hardware deinterlacing only means: do not touch the video at all, mark it at interlaced and send it this way to the video renderer. The renderer then usually let the GPU do it. With this method, you can't use ffdshow postprocessing. ffdshow passes the postprocessed video to the video renderer! If you post-process interlaced frames without deinterlacing first the result will be bad.

It's in the profiles as a pre-caution, so that the picture doesn't get ruined incase a codec doesn't do GPU based de-interlacing. If frames are already marked as progressive then the ffdshow Deinterlacing does nothing.

Various options only show up in GPU drivers based on the connection type or only have effect on some connections. So it can be different based on how your display is connected what is available and what not.

The Color Fromat Setting is a general setting. It is either right for your TV or not. You will see a difference right away on the Desktop. Colors should be more "vibrant" instantly.

When you send the color information in RGB and you TV's video processor doesn't handle it correctly, everything will be washed out (black becomes a bit more grey). So either RGB or YcBrCr is right for your display to stop it from tampering with the color range on its own.

It is just HOW the GPU sends the color information to the display. It doesn't alter the colors! So no danger here for games or other stuff. Just try what is right for your display. Usually with YCbCr the display's video processor doesn't try to change the color range on its own or do other post processing stuff. No difference between the settings: stay with the default.

The Dynamic Color Range need to be adjusted in the same manner. If your display doesn't like the full RGB range you will either see washed out picture or crushed blacks. But always try to set the Color Format from RGB to YcBrCr first as this solves most issues. Afterwards give the color range a try, too. But only if the picture is still washed out or if you have crushed blacks. No difference? Stay with the default. The color range can be application specific. So if you need to use 16-235 for videos it is a good idea to put it into a profile.

Usually YCbCr and 0-255 is the correct combination for telling mist TVs: "Leave my colors alone, dude!.

For my Samsung and my onboard Nvidia I need to do the following:
- Color Format: YCbCr or I have a washed out pictures, meaning blacks are not black and whites are too white.
- Color Range for Media Portal: 16-235 or I have crushed blacks (meaning black is too black) on MPEG2 streams (codec thingy...)

 

[FireAza]

Thanks for the info Scythe42!

Just one thing, as doveman pointed out, changing the display output in the GPU itself might not be for the best if you use a regular PC monitor on the same computer. Would setting the color output and RGB conversion in ffdshow achieve the same results as setting them in the nvidia control panel? This would be preferable to me, since they only take effect while MediaPortal is running.

And just with regards to LAV, the RGB output option, does this override ffdshow's setting? Like, do I have to set both to the same? (or is that why you chose the "Untouched" option?)

*EDIT* I've just noticed something, and I thought perhaps you could shed some light on it. For awhile now, I've sometimes noticed when watching videos on MediaPortal that objects appears to show though things that shouldn't. Uh, it's kinda hard to explain, but here goes. I often see this with animated content, say for example a character is standing in front of a railing which is made up of thin bars. Sometimes you can "see" the bars "continue" though the character, even though it's not being drawn like that. It most seems to happen with bright scenes. I've been using the RGB 16-235 output level option in ffdshow, and I can't seem to recall seeing this weird phenomenon recently. Any clues why this might be?

 

[Scythe42]

If you use a regular monitor it should be RGB/0-255. Only TVs might require YCbCr and/or 16-235.

And this is general for the TV when it can't handle RGB/0-255 correctly. It is just what your display's video processor can handle. If it is only with some codecs and the rest is fine, you do adjustments inside the codec.

The RGB32 conversion in ffdshow just makes sure that the full RGB range is send to the renderer and nothing gets lost during what the GPU renderer does. This is just a precaution, so that nothing gets cut of before the picture is send to the renderer.

The NV12 in/output you usually get from MediaPortal is fine for the renderer, too. I just like to be sure I always send the same stuff to the GPU to avoid any potential issues with some codecs. Especially on my development machine where I do experiments now and then.

With RGB32 I provide the full color range of a video to the video renderer. Nothing will be cut of, nothing will be added. The rest is up to the GPU. But as said NV12 is fine, too. Not going into explaining the differences of the color formats here. So consider the to RGB32 setting an optional step. It doesn't change the colors, only the format. And from experience all GPUs I ever came across like RGB32 the most. But as said, consider this setting optional to avoid issues.

The GPU driver decides after the renderer has rendered the picture based on the display settings if it should send the colors in RGB or YCbCr format and/or limit the color output if necessary. This happens AFTER the renderer and just defined the capabilities of the display itself.

It is just what your display can handle. First: Color Format. And if you still have issues adjust the Color Range.

You would have the same problems with games, desktop apps and other stuff with washed out colors or crushed blacks. It is just what your display likes. Has nothing do to with MediaPortal. If the settings are wrong they are wrong for everything!

But most people only notice it during videos and not applications or games because they know how the colors look on their DVD player.

And they often try to fix stuff in games with some gamma correction. If you ever needed to touch some brightness/constrast/gamma stuff for games, you have a general problem that display is not properly configured or the setup of the display is completely screwed. It should never be necessary unless for CRTs or a display that is miles way from the correct color representation (some people actually set their computer monitors to unbelievable crap...)

To sum it up again:

• Computer Monitor are designed for RGB/0-255
• TV are designed for YCbCr/16-235. Where some do 0-255 to 16-235 automatically when needed. You need to check if 16-235 is necessary for your display.
• If you have a problem only in video playback check the codec settings in regards to color output
• Some TV can handle RGB/0-255 correctly
• Some Receivers do all the stuff when connected over HDMI as they see the color format/range and what every component likes most and convert it on the fly.

You can blame Nvidia and ATI here. There drivers don't really talk over HDMI to the display or they would know what the display really likes to display correct colors! But they don't. Same problem with 23,976Hz. No GPU I every came across does this 100% stable and exact. Not a biggie though.

In the end it all depends on your display. You need to try it out. It just take a few seconds to see it on the desktop with the default win wallpaper right away.

1. Try to use YCbCr output instead of RGB if you have washed out colors
2. If you still have problems (washed out colors or crushed blacks) change the color range from 0-255 to 16-235
3. If this doesn't help try the RGB/16-235 combination as a last resort.
4. If it is only in video playback or some videos > use codec setting to adjust colors

And as said this is depended on your display, unless something else is screwed up on the computer in general that effects stuff.

It might also be possible that your display has different kind of inputs to automatically correct color formats and range. Check if you can switch with them as well. Again depends on the software on the TV. But usually doing this on the HTPC is easier and quicker.

Games, Desktop, Web Browsing will suffer from the same color problems as Media Portal. Either your display can handle RGB/0-255 input right or it can't. There is no "only in this application" (unless the application screws with the color range on its own - but never saw that). Your display's video processor doesn't change magically because you are running a different kind of software.

Some Media Players might be the exception to the rule as they might override GPU settings. Especially if they use an own renderer. But MP does this not as it doesn't have any kind of post processing at the moment built-in. And it relies on your codec installation and settings. No special/hidden configs here.

You once setup your display right - you are done. Afterwards make sure the codecs don't play around with it again. And you will have the correct colors for you display everywhere. If this is not the case it is something other in your setup.

The thing "bar goes through character" sounds like a de-interlacing artifact. I know this from the first seasons of my South Park DVDs. A line is present in one of the interlaced frame but not the other. Happens for me when I let the GPU do deinterlacing/scaling (meaning no postprocessing) on my box. But I need the video stream and the direct show graph to reproduce it and tell you what it is.

 

[Scythe42]

On a side note: There is no perfect way to do all this stuff. Various options exists in various components. Just adjust them there where it feels best for you.

 

[FireAza]

Thanks for the info Scythe42! With regards to color settings, I notice that the nvidia control panel actually has separate settings for each monitor. This would mean the monitor I use for gaming should be unaffected. However, it would be more convenient for people who are following this guide to have the colors set by the ffdshow profiles instead. Are there any advantages in setting the color settings in the nvidia control panel instead of ffdshow?

 

[Arturas1976]

Yesterday played with TV settings a bit. And solved my longrun stuttering problem

I have pioneer LX-508D plasma and in PC input mode it (as it seems all TV do and that I have read long ago) has fixed 60Hz
refresh rate BUT on the screen info when input is 50Hz shows 50Hz!!! And that was misunderstanding a lot!

Switching to inpu VIdeo made everything perfect clear and smooth.

What a nice day

Next will be playing with my new toy - Spyder4Pro calibrator

 

[Scythe42]

The YCbCR settings should be done depending the display's needs as every application will suffer from a washed out picture if the the display's video processor doesn't handle colors in RGB format correctly. As said, this usually solves any problems with a TV's video processor. This is an essential setting - you need to set it to the correct format of you display. Basic setup if you use TV instead of a computer monitor. This must be right.

If you still have to - and only if you have to set the color range to 16-235 as well than you can do it as well with ffdshow or the codecs. Whatever you prefer. The load the the CPU is minimal. Please note that this setting in the control panels only applies to media players. RGB/16-235 is very likely a thing for that works for computer displays, where YCbCr is not an option.

But note if YCbCR solves the problem for a TV and you provide 16-235 in ffdshow as well you will have washed out colors, where as the setting in the GPU will not when the color range is already properly set. So going for the GPU route if you limit the colors range as well is usually a better option. Think of it like this: with YCbCr the TV does 0-255 to 16-235 on it's own and you can just provide 0-255 as you want and don't need to care anymore.

Of course even your display needs YCbCR color format you can ignore it and just to 16-235 with ffdshow. Then MediaPortal will be the only thing on the PC not being washed out

For computer display you might have to use RGB/16-235 to avoid crushed blacks. In this case just doing it in ffdshow instead on the GPU profile is perfectly fine (or codecs if you want). But as you might use a lot of different codecs it might be easier to do it in ffdshow and leave the codecs alone.

If you go the ffdshow route than you can apply this to all profiles. HD streams usually have the correct color information. Usually onlyy mpeg2 and xvid suffer from not correct color range information in the stream. If the color range is already 16-235, then ffdshow doesn't do anything, therefore it is safe to have it in all profiles.

Yeah, complex topic. Basically is comes down to: Does my display handle RGB color format? If not, can I use YCbCR format to solve my problems? If not go the 16-235 route where ever you like.

Looking forward to your updated guide!

 

[Arturas1976]

This Video postprocessing is used for Video only or is reasonable in TV also for SD upscale?

 

[Scythe42]

Sure, TV is just another source for a video stream.