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  1. I am using this to check values.

    coloryuv(analyze=true)
    limiter(16, 235, 16, 240, "luma")
    limiter(16, 235, 16, 240, "chroma")


    I know a few red dots here and there is nothing to worry about but I was told long ago it's not an issue unless I see large areas of red.

    I have not had to deal with this much appearing in the video before. Does this look something I should worry about? I can get rid of them by brightening the image and raising the values from 12 to 16, but then I think it looks too bright. This horror movie is overall very dark or supposed to look dark.

    https://i.imgur.com/RkJGbDj.png
    https://i.imgur.com/EI2zVNv.png
    https://i.imgur.com/lx8myMG.png

    Here they are again without the red dots and values on screen

    https://i.imgur.com/XeRk2QX.png
    https://i.imgur.com/wIJEHnO.png
    https://i.imgur.com/fwIxj74.png

    Can I leave it like this and not have playback problems?
    Last edited by killerteengohan; 19th Feb 2019 at 16:38.
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  2. It looks like you have a lot of crushed blacks. If your display is properly set up you you're losing some detail in those dark areas.
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  3. I guess it's my fault their crushed because of adjusting levels. The source already had quite a bit of red spots on it, but I intensified it a lot more with this filter.

    I was trying to brighten it up a little and remove the white tint over the image. I achieved it with this and personally think it looks better.

    ColorYUV(levels="TV->PC")
    ColorYUV(off_y=11)
    smoothtweak(saturation=0.98, brightness=2, contrast=1.00, dither=-1, interp=0, limiter=false)



    Here is a before and after image

    http://screenshotcomparison.com/comparison/130517
    http://screenshotcomparison.com/comparison/130518
    http://screenshotcomparison.com/comparison/130519


    I don't really notice much loss and I think it looks better this way. Maybe some of the darker areas like patches on hair I notice it going very dark, but that tiny bit of possible loss doesn't seem to bother me. I still think it looks better. The only one with more than obvious loss to me is the third example.

    I can get rid of the red by increasing the value of y to 14, but it begins to get white again. Is there a better way to adjust it so it doesn't look like it's covered in a grey tint and increase brightness a tad bit without adding too much white? Is mine completely off even though I think it looks better?
    Last edited by killerteengohan; 19th Feb 2019 at 22:06.
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  4. Originally Posted by killerteengohan View Post
    ColorYUV(levels="TV->PC")
    This is crushing your Y<16 levels. Values below 17 all become 0, values above 234 all become 255.

    Originally Posted by killerteengohan View Post
    ColorYUV(off_y=10)
    That isn't enough to bring levels back up to the legal range. And may be further blowing out brights.

    Provide a video sample for a more reasonable procedure.
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  5. 720p resolution or the original 1080p resolution?
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  6. I tried to get something bright in the darker scenes and it seems to be the flashlights and candles that get too bright, so I tried to get that in the sample.
    The lighter day time scene is just in case you need it for comparison, so you know if your going too bright on the suggestion you may make.


    Sample 1 (Dark Scene)

    https://mega.nz/#!NwhRSIQD!Wws7dqWUs143nGzl3wnx3g4bg3lQM2nFX6fl2_yd8Jw


    Sample 2 (Lighter Scene)

    https://mega.nz/#!904TjSpJ!f47rSeRrDLiq_XwSQQLD4oHXEqTlT4Kfd_BaJdSVD-I
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  7. Here is another dark scene that's probably better for viewing. It's got much better candlelight shot and you can overall see more in the video.

    https://mega.nz/#!044R0S7B!eV4i-ooyEN_oeZHzb68xDeiSe4_ylyTGpNDEu0OBO3w
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  8. Not sure if this will help but here is a Blu-Ray and DVD screenshot of the same frame.

    Blu-Ray = https://i.imgur.com/cvOJ4fn.png
    DVD = https://i.imgur.com/4ZRUlfg.png
    Last edited by killerteengohan; 19th Feb 2019 at 22:08.
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  9. What are those from? Your source or after your processing? There aren't any significant superdarks or superbrights in them. You need to provide a sample of your source if you want help with it.
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  10. It is the source Blu-Ray. All I did was resize it to 720p for lower file size so your not downloading a huge file sized sample. I didn't do anything else to it. If you need it made differently please tell me how to get you what you want without having to give the entire 35GB m2ts file.

    Apply this to the sample video and you should get what the screenshots I shared earlier look like when I crushed it.

    ColorYUV(levels="TV->PC")
    ColorYUV(off_y=11)
    smoothtweak(saturation=0.98, brightness=2, contrast=1.00, dither=-1, interp=0, limiter=false)

    Placing that in and removing that will give you the before and after comparison screenshots I shared earlier on screenshotcomparison.

    http://screenshotcomparison.com/comparison/130517
    http://screenshotcomparison.com/comparison/130518
    http://screenshotcomparison.com/comparison/130519

    It gets rid of the white tint over the picture as you can see, and blacks look black again. But I guess it crushes blacks and the bright things like candle light become obviously too bright or shiny.
    Last edited by killerteengohan; 20th Feb 2019 at 00:27.
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  11. The source only has a bunch of red dots in the dark scenes, not solid areas of red like when you add the filters I did to make the darks look better to me.

    I noticed I can set limiter=true in smoothtweak like this and it all the values go back in the legal range and the tint is still gone. I don't know if this is destroying anything though.

    ColorYUV(levels="TV->PC")
    ColorYUV(off_y=11)
    smoothtweak(saturation=0.98, brightness=2, contrast=1.00, dither=-1, interp=0, limiter=true)
    Last edited by killerteengohan; 20th Feb 2019 at 02:10.
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  12. I misunderstood. I thought your source had the illegal values and you were trying to correct them.

    The adjustments you are making are blowing out the brights. Adding limiter=true to SmoothTweak() will clamp everything between 16 and 235, crushing the superblack and superwhites. I think that's the worst solution. I don't think the source really requires any adjustments. But if you want to pull the black level down a bit I'd skip the other adjustments and just use SmoothTweak(contrast=1.005, brightness=-1). That keeps the white level where it is and pulls the blacks down a bit. Maybe SmoothTweak(contrast=1.01, brightness=-2) if you want the blacks a little darker.
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  13. Yeah, I just wanted the slight whiteness/grey over the entire image to be reduced like what I was doing to it was doing and to make things that were too dark appear brighter as well. It looks fine and better to me on my PC the way I was doing it, but when I played it on my TV and compared the two on TV, it actually looked too dark and things were less visible. I certainly preferred the unaltered on my TV.

    I can see where its blowing up the brights. This part in particular is pretty obvious. I could not find a way to get PC levels to not do this to the flashlight in this image.
    Before = https://i.imgur.com/clGQB0P.png
    After = https://i.imgur.com/dWcr78z.png

    The SmoothTweak(contrast=1.01, brightness=-2) you suggested does indeed lower the white/grey tint like I figured, but everything else appears darker as well. Too dark for certain things to be visible, thats why I did not use brightness lower when I originally tried it before asking on here. The changing to PC levels made everything else appear brighter or more visible, while doing the same thing with the white tint removal as can be seen in the screenshot comparison links. I wish it could go the PC level without blowing up the whites too much. I guess I will just do a version that not altered any for when I am viewing on TV and do a PC levels adjustment for when I am watching on my computer.

    Thanks for your time you gave!
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  14. If you want to see more dark detail without blowing out brights use ColorYUV(gamma_y, gain_y, off_y) instead of Tweak(cont...). Maybe along the lines of ColorYUV(gain_y=5, gamma_y=50, off_y=-9). Levels() also has a gamma setting.
    Last edited by jagabo; 22nd Feb 2019 at 17:34.
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  15. Originally Posted by killerteengohan View Post
    The SmoothTweak(contrast=1.01, brightness=-2) you suggested does indeed lower the white/grey tint like I figured, but everything else appears darker as well
    To keep that from happening I often use YLevelsS combined with Tweak's Brightness and Contrast settings.
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  16. Instead of setting limiter=true in smoothtweak, I was trying limiter like this, hoping it would leave blacks alone and only clamp brights/whites.
    limiter(0, 235, 0, 240)

    I still did that overbrightening to the flashlight in the above before and after pic though.

    I'll try your new suggestion right now.
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  17. I don't worry much, myself, if lights go over 235. If 'normal' whites, like shirts or white walls go over, then I'm sure to fix it.
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  18. Originally Posted by manono View Post
    I don't worry much, myself, if lights go over 235. If 'normal' whites, like shirts or white walls go over, then I'm sure to fix it.
    I generally agree with that. But if lights are blown out, it's likely there are other bright shots that will get blown out too.
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  19. Originally Posted by jagabo View Post
    Originally Posted by manono View Post
    I don't worry much, myself, if lights go over 235. If 'normal' whites, like shirts or white walls go over, then I'm sure to fix it.
    I generally agree with that. But if lights are blown out, it's likely there are other bright shots that will get blown out too.

    I didn't mind the lights much either because if you look at this DVD shot of the same flashlight pic as above, it looks just like when I make the Blu-Ray PC levels and you cannot see the separate beams in the flashlight there either. It's just a solid white like when I make Blu-Ray PC levels.
    https://i.imgur.com/tduRjAe.png

    Honestly the only time I could see the brights reach 255 after changing the levels to PC, were parts where candle fire or flashlights were being shined. With the exception of one scene at the beginning when its daylight out. The whites here look really overblown as you can see.
    Before = https://i.imgur.com/UyOwgH2.png
    After = https://i.imgur.com/smVe1vY.png


    The ColorYUV(gain_y=5, gamma_y=50, off_y=-9) certainly does what I was looking for. The bright flashlight actually stayed correct looking and the earlier scene does not look overblown. A side effect seems to be saturation or colors appear to have lost saturation or get washed out looking. Is there a proper way to help that? I tried increasing saturation, but the colors look like more saturated versions of the washed out colors and not like how they were before the adjustment.
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  20. You shouldn't be making BD with full range YUV. It should be the same limited range YUV as DVD and every other consumer format.

    Regarding loss of saturation when brightening the picture -- that's normal. You can increase the saturation too. With colorYUV saturation is cont_u and con_v.
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