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  • Sat, Jan 14 2012 12:04 AM

    • Nathan Grout
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    Avid Color Space / Display Color Space Mismatch

    Background Info

    All of my editing in Avid is in the YCbCr 709 color space. This is an 8-bit color space (values from 0-255), where black is defined as 16 and white is defined as 235. Anything below 16 is super black and anything above 235 is super white.

    My normal HP computer displays use the standard sRGB color space. They define 8-bit black as 0 and white as 255.

    Because Avid defines black above where my displays define it and white below where my displays define it, everything in Avid appears to have a lower contrast than it otherwise would. Here is an image that demonstrates this: http://i1.creativecow.net/u/201505/709vsrgb.jpg

    This image is made from screenshots from Avid and Quicktime (which represents the native color space of my monitor). You'll notice the lower contrast on the Avid displayed images that I mentioned above. It's subtle, but is most noticeable in the differences in the brightness of Woody's vest, the highlights on Woody's belt, and in the details in the shadows behind the dresser.

    (Note: Quicktime is displaying an export from the sequence that Avid was displaying. This export used the same codec and color space as the imported footage in the sequence. As such, the export process should not account for any of the display discrepancies.)


    Question Time

    I like that Avid encodes my video in a way that doesn't permanently crush my footage. I don't like that Avid displays my footage inaccurately for my displays. Is there a setting that I can change in Media Composer 6 to resolve this problem? Alternatively, is there an easy way to change the color profiles of my displays in Mac OS X Lion (10.7.2) to better match how Avid displays images?


    Solutions I Have Tried

    -I have searched the forums.
    -I've Google'd it.
    -I have looked through Avid's settings and haven't found anything on my own.
    -I have tried to manually adjust brightness and contrast of my displays while looking at the pluge portion of standard color bars in Avid, but since they are computer displays rather than broadcast monitors, this was unsuccessful.
    -I have calibrated my displays using a Spyder3Elite colorimeter, but this accurately calibrates the displays to their own color space, not to the color space of Avid. I have looked for alternative Spyder3Elite settings that would better match Avid's color space, but to no avail.

     

  • Sat, Jan 14 2012 1:51 AM In reply to

    • Stu
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    Re: Avid Color Space / Display Color Space Mismatch

    Firstly, I personally don't trust using any video player when it comes to displaying video.  VLC displays differently, QT displays differently, WMP displays differently, they all have unknown ways of displaying the image whether the program decides to stretch the regions or not.

     

    Secondly, we are assuming that you are fully aware of how footage looks, vs what it actually is, and it looks like you are aware of how avid treats/displays color spaces.

    ngrout:
    I like that Avid encodes my video in a way that doesn't permanently crush my footage. I don't like that Avid displays my footage inaccurately for my displays. Is there a setting that I can change in Media Composer 6 to resolve this problem?

    To quickly answer this, sorta.  You can tell avid how to display your media on the monitor when in FULL SCREEN PLAYBACK.  Because you do all your color correcting by the 709 "16-235", your blacks aren't a true black, you are staying in safe level territory.

    To see your images, like the way they would look on the web "0-255", you can simulate that when you view in full screen by doing this: Settings>Full Screen Playback>select the box "expand luminence for computer displays".

    Ctrl+Shift+F or Cmd+Shift+F, you will now see your 709 optimised images as if it were stretched to web color space.  Meaning your "16" is now "0", and your 235 is now 255.

    IF you're outputting to DVD, you need to keep all rendering to 709/601.

    Final Cut Pro on the otherhand, I can never figure out if my encoded videos have been encoded properly.  I'm very used to PC, truley knowing what my footage looks like.

    Lenovo E31 Thinkstation - MC 8.3.0 - Win7Pro SP1 - 1x Xeon 1275v2 - Kingston 32GB 1600MHz ECC - Quadro2000 /// w540: Win8.1 (not pro) - 4th gen i7 4710MQ... [view my complete system specs]
  • Sat, Jan 14 2012 2:09 AM In reply to

    • Stu
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    Re: Avid Color Space / Display Color Space Mismatch

    I also wanted to add this:

     

    I trust my scopes, specifically Waveform Monitor within Avid to determind if my footage is importing correctly (when I'm not fast importing).  For this case, I will only talk about importing, I have not experimented with AMA'ing then Consolidating/Transcoding.  Also keep in mind, I'm talking about footage in it's original state, NOT media transcoded from a 3rd party program to a codec like DNx (see ***)

     

    Normal VIDEO cameras, always shoot in the 709 levels, aka "16-235".  Keep in mind some cameras have highlights that extend past 235, but it's shadows never go below 16.  When working with this kind of footage, you import it as 709 colorspace in the import options.  (If you are FAST importing ORIGINAL media, everything is all good)

     

    DSLR cameras, record it's video in the entire 0-255 range.  When importing into Avid, change your import settings to interpret as RGB.  It takes those ranges, and squashes it to a 16-255.  I've done tests and found that importing as is crushes the blacks/highlights a bit (plus it will then look like full blown 0-255 in avid)

    Lenovo E31 Thinkstation - MC 8.3.0 - Win7Pro SP1 - 1x Xeon 1275v2 - Kingston 32GB 1600MHz ECC - Quadro2000 /// w540: Win8.1 (not pro) - 4th gen i7 4710MQ... [view my complete system specs]
  • Sat, Jan 14 2012 2:11 AM In reply to

    • jef
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    Re: Avid Color Space / Display Color Space Mismatch

    ngrout:
    All of my editing in Avid is in the YCbCr 709 color space.

    Hi,

    May I ask what your intended viewing environment is?  Is it broadcast TV? Is it projection in a theater?  Is is web based delivery to be viewed on a computer screen?  All these methods have different display technology.  Once you settle on that then you can figure out how to monitor correctly.  This is the most important question.  Your post does not seem to state this.

    Once we know that, then maybe we can offer suggestions.

    Jef

     

     

     

    Avid DS 11.0.2 R.I.P | MC "Well, it depends ..." mostly 8.10.0 but playing w 2018.11| OS 10.11.x - various MacPro Towers - home system MacPro... [view my complete system specs]

    _____________________________________________

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    Senior Editor

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  • Sat, Jan 14 2012 6:12 AM In reply to

    • Nathan Grout
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    Re: Avid Color Space / Display Color Space Mismatch

    jef:

    May I ask what your intended viewing environment is?  Is it broadcast TV? Is it projection in a theater?  Is is web based delivery to be viewed on a computer screen?  All these methods have different display technology.  Once you settle on that then you can figure out how to monitor correctly.  This is the most important question.  Your post does not seem to state this.

    I'm outputting at various times to web, DVD, and Blu-Ray.  My decision to work in the YCbCr color space is determined more by codecs than by output, since Avid 6 will only let me import to DNxHD 36, 115, and 220 while set to YCbCr.  When set to RGB it only gives me 10 bit uncompressed RGB, ProRes 4444, and DNxHD 444.  All of these are much bulkier than what I need.

    Stu:

    To see your images, like the way they would look on the web "0-255", you can simulate that when you view in full screen by doing this: Settings>Full Screen Playback>select the box "expand luminence for computer displays".

    This seems like exactly what I want.  However, this option does not seem to be working for me in MC 6, and I have heard from another editor who is having the same problem.  The image looks exactly the same with this option toggled on or off.  So we might have a bug to report there. But why can't we have this as an option for the source/record monitors?  Seems like it would be easy enough.  I think I'll make my way over to the feature request forum.
    Stu:

    Firstly, I personally don't trust using any video player when it comes to displaying video.  VLC displays differently, QT displays differently, WMP displays differently, they all have unknown ways of displaying the image whether the program decides to stretch the regions or not.

    (...)

    Final Cut Pro on the otherhand, I can never figure out if my encoded videos have been encoded properly.  I'm very used to PC, truley knowing what my footage looks like.

    I guess this is where we differ.  Wait, let me backup.  I can definitely understand wanting to see the full 0-255 image (like Avid does).  It certainly makes sense to have this available as an option.  Ok, now back to where we differ.  In my experience (mostly using OS X), Final Cut Pro 7, After Effect, Photoshop, Quicktime, etc. all consistently use the clipped 16-235 range, just as a broadcast monitor would.  Certainly I can't be the only one to have noticed that the black filler that Avid uses doesn't look like the same black that is seen in Photoshop.  For Avid not to have the option for finished-style image display seems short-sighted.

    In essence what we are talking about are the two most common LUTs.  A full, raw 0-255 is the default LUT for Avid, while 16-235 is the default LUT for Quicktime, the web, Photoshop, After Effects, Final Cut Pro 7, and as I understand it, DVD and Blu-Ray.  With a list like that, doesn't it make sense for Avid to support it?

     

  • Sat, Jan 14 2012 6:49 AM In reply to

    Re: Avid Color Space / Display Color Space Mismatch

    Unfortunately, you can't. The color controls of video overlay (the function that governs GPU accelerated playback in applications) is seperate from your desktop color profile. QT, FCP, Avid all have this issue.

    Second, QT has a notorious gamma issue (Google it), even FCP X seems to have this issue.This is the likely source of the discrepency you are seeing.

    If you care about colors these much, use scopes and proper broadcast monitor.

    MC 8.6.1, Windows 10, ASROCK X99M, Intel 5930K, Zotac GTX970, 32GB RAM, Transcend 512GB M.2 SSD & Dell U2713H. MBP 2012 Thunderbolt, OSX 10.10.5, MC... [view my complete system specs]
  • Sat, Jan 14 2012 7:21 AM In reply to

    • Nathan Grout
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    Re: Avid Color Space / Display Color Space Mismatch

    My googling led me quickly to this page, which rather thuroughly addresses how Final Cut Pro and Quicktime sometimes do some weird gamma switching to RGB clips.  Since we are talking about clips encoded in the YCbCr color space, this does not seem to be the issue.

    And I'm still interested in trying the "Expand Luminence for Computer Displays" setting because I am very confident that what Avid calls black (as with it's filler) is not the same black that is used by my computer monitor.  Quicktime aside, the black of my audio meters below the source/record monitor is darker than the black of the filler in the source/record monitor.  I want to see black as black, just as on a calibrated monitor (I just don't think I should have to buy one).

    If nothing else, I guess I can apply color correction to a track of filler above my work and set the black point on the master curve to (16,0) and the white point to (235,256). It gives me the look I want in Avid, I just have to remember to turn it off for export.

  • Sat, Jan 14 2012 7:30 AM In reply to

    • Nathan Grout
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    Re: Avid Color Space / Display Color Space Mismatch

    Here is a link to a screenshot showing the difference between the black filler used by Avid (16, seen towards the top) and the black used by the operating system and Avid's audio meters (0, seen towards the bottom).  Feel free to take this into Photoshop and eyedropper the two versions of black if you have a hard time seeing the difference.

    What is really black?

  • Sat, Jan 14 2012 3:32 PM In reply to

    Re: Avid Color Space / Display Color Space Mismatch

    Nathan Grout:
    My googling led me quickly to this page, which rather thuroughly addresses how Final Cut Pro and Quicktime sometimes do some weird gamma switching to RGB clips.  Since we are talking about clips encoded in the YCbCr color space, this does not seem to be the issue.

    The problem is not limited to RGB. QT does not handle YCrCb correctly or at least consistently. And YCrCb is nothing more but a derivative of RGB.

    You should really use the scopes to judge proper levels. I am unsure why you are using a RGB (monitor, GPU, color profile, etc) environment to critically judge a YCrCb video. Second, overlay only kicks in during real time playback. The moment you stop the video and or do a screen grab it is the desktop RGB color profile that governs it.

    I am not saying there is nothing wrong. Obviously there is a difference. Using the scopes (software or hardware) will give an idea which one is off. And I am unsure why you would use expand luminance since this function is not standard practice in the computer video world. This is not like NTSC setup.

    BTW - Full Screen Playback in Avid does have that function but again, not sure if this is the way to go to critically evaluate color levels.

     

    MC 8.6.1, Windows 10, ASROCK X99M, Intel 5930K, Zotac GTX970, 32GB RAM, Transcend 512GB M.2 SSD & Dell U2713H. MBP 2012 Thunderbolt, OSX 10.10.5, MC... [view my complete system specs]
  • Sat, Jan 14 2012 3:49 PM In reply to

    • watchman
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    Re: Avid Color Space / Display Color Space Mismatch

    I have exactly the same problem and it drives me mad. Why is MC designed this way? It's wrong. It's called 'Media Composser' not 'Broadcast Media Composer'. I just want to start and finish my editing in Avid, on my laptop, without crushing or stretching any data from 5d's CMOS sensor. And now my Anamorphic Mask is not black, but gray, and brighter then the deepest shadows of my footage. In scopes my footage looks fine, but the mask doesn't. It's not acceptable.

    I hear many experienced Avid users justifying such behaviour as 'traditional' or 'historical', but honestly it's 2012 and televison is only a fraction of all media channels. 

    I searched world wide web and didn't find a solution (except of CC-ing fillers, which anyway won't work in Dip to Black without affecting the rest of the footage.)

    Avid must fix this!

    MC6, Mac OS X Lion 10.7.2, MacBook Pro, 13-inch, Early 2011, 2.7 GHz Intel Core i7, 8 GB 1333 MHz DDR3, Intel HD Graphics 3000 512 MB, APPLE SSD TS512C... [view my complete system specs]
  • Sat, Jan 14 2012 4:28 PM In reply to

    • watchman
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    Re: Avid Color Space / Display Color Space Mismatch

    And masks are unscopable. (Or does that green line present the scoped values for the filler, which is 16?)

    MC6, Mac OS X Lion 10.7.2, MacBook Pro, 13-inch, Early 2011, 2.7 GHz Intel Core i7, 8 GB 1333 MHz DDR3, Intel HD Graphics 3000 512 MB, APPLE SSD TS512C... [view my complete system specs]
  • Sat, Jan 14 2012 8:40 PM In reply to

    Re: Avid Color Space / Display Color Space Mismatch

    The green line is your mask.

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  • Sat, Jan 14 2012 8:42 PM In reply to

    Re: Avid Color Space / Display Color Space Mismatch

    watchman:
    Why is MC designed this way?
    Because it adheres to video standards. And I for one am glad.

    I understand the need for others to be able to work in other color spaces, though. It's just a step further than just changing the levels of the masks, it's about anything inside MC needing to be able to work inside a given color space.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sat, Jan 14 2012 9:59 PM In reply to

    • Stu
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    Re: Avid Color Space / Display Color Space Mismatch

    It seems like some of your original questions have been lost.  Let's refresh back to your original set of questions.

     

    "FILLER in avid is... what?"

    The filler black in avid is at 16 which is black for broadcast.  I believe this is very silly of Avid.

     

    3rd party AVX apps within Avid.  Programs like BorisRED/AvidFX, stay within this 16-235 range.  You can stretch contrast all you want within those integrated compositing programs, but once you apply and bring to the avid timeline they will be safe withing the 16-235 range.

    BCC effects give you the option under general, to select or deselect if you want those effects to be 'broadcast levels' or not, aka staying within 16-235, or the whole 0-255.

    "auto contrast" within the CC tool in avid, will auto determind the contrast and will never stretch it past the 16-235 levels.

     

    My personal suggestions is this: When working with anything, stay within the 16-235 spectrum, always.  Because when you turn around and do end up encoding for web, the web formats actually automatically stretch the 16-235 to the full 0-255 range, for pure black and pure white.

     

    "We differ between seeing things between mac avid and FCP, vs PC avid"

    Apparently the "expand luminence" for full screen playback only works when on a PC, no difference is shown when on a mac... here's why...

     

    FCP, or the mac OS in general truely makes things simple but in a scary pain in the butt sort of way.  When you see any clip in final cut, it automatically takes your broadcast standard 16-235 video footage, and will stretch it to the COMPUTER's monitor, making 16 pure black and 255 pure white.  <<< that is what is I find frustrating because...

     

    I've shot HVX200 footage knowing that I have detail in my shadows, and I know the HVX does not have blacks lower than "16".  Guess what, in FCP, my detail in the shadows are no where to be found, crushedIn Avid, both mac and PC, I see all the detail in those shadows.  In FCP, bringing up the shadows without sending to color is just really hard and very painful.  FCP's in-house CC tool is no where near like avid's in-house CC tool, because avid has curves.  If I knew I were to be doing a project that I was shooting and was going to FCP, I would actually raise the master PED 2 or 3 clicks just to make sure I don't 'loose visibility' of the shadows.  Also, a majority of video cameras actually have head room, meaning that there is actually detail in the highlights found in the 235-255 range, of which FCP will chop off! (chop off as in not displaying because of mac's gamma shift, not distroying information)

     

    Have all of your questions and concerns been discussed?

    Lenovo E31 Thinkstation - MC 8.3.0 - Win7Pro SP1 - 1x Xeon 1275v2 - Kingston 32GB 1600MHz ECC - Quadro2000 /// w540: Win8.1 (not pro) - 4th gen i7 4710MQ... [view my complete system specs]
  • Sat, Jan 14 2012 10:46 PM In reply to

    • Nathan Grout
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    Re: Avid Color Space / Display Color Space Mismatch

    Stu:

    It seems like some of your original questions have been lost.  Let's refresh back to your original set of questions.

    Agreed, but I'm partly to blame Smile.  It's become a battle between those who like seeing 0-255 and those who want to see 16-235.  I am satisfied that Media Composer won't show me the 16-235 that I want to see in the source/record monitors.  And I'm frustrated that that's the case.

    When one shoots on an advanced format camera that uses a LUT, one does not typically edit the raw, full range, low contrast footage, but first applies the LUT so that the relevant visible portion of the data is shown and everything else is clipped.  Color correction can, however, utilize the information contained in the invisible portions of the data.  This is how editing applications that clip to 16-235 work.  For many it's a sensible and desirable way to work.  If you would like to see the full range un-LUT'd 0-255 image, be my guest.  I would like the super-blacks and the super-whites crushed as they will be on output.  We can agree to disagree, but I think it's a silly software limitation to only use one or the other.

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