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  1. Member
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    As part of my video, at the end I need to fade in a simple logo consisting of two colours, but the two colours do not fade in at the same time in the rendered video as they do in the preview for the video editing software.

    I am using Sony Movie Studio 13, and have compressed/rendered the video using both the 'Sony AVC/MVC' render/compression option and the 'Mainconcept AVC/AAC' option, but the problem remains.
    I think I have played around with all the settings in both the codec/rendering settings windows, and with the settings within the editing interface (the events) and options too.

    What's going on? Is it something about how the H.264 codec works which means it is impossible to avoid?

    Do I need access to extra options for controlling how colours are processed in the codec options? Maybe options that would only be provided in Vegas Pro? Something to do with colour bit depth, or chroma sub sampling or something like that?

    Below are two images showing a stage of progression in the fade ins for the rendered video where the red part of the logo begins fading in first, and the preview in Movies Studio where both of the different coloured parts of the logo fade in at the same . . .

    Click image for larger version

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    Click image for larger version

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    Last edited by muel2002; 29th Jul 2017 at 10:44. Reason: forgot to include info
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  2. Originally Posted by muel2002 View Post
    As part of my video, at the end I need to fade in a simple logo consisting of two colours, but the two colours do not fade in at the same time in the rendered video as they do in the preview for the video editing software.
    How was the fade controlled in vegas ? Was this a 1 layer , single fade setup or something else ?


    Is it something about how the H.264 codec works which means it is impossible to avoid?
    No, it's not a h264 problem (because it definitely works ok for other people), but it could be a playback setup problem.

    You probably took the screenshot in vlc (because image says vlcsnap...), and this is probably not the same frame, but there is a slight color shifting which makes me think at least partially a rec601 vs. rec709 issue


    1) What happens when you re-import the export back into vegas (instead of VLC) to check the timing and colors ?

    2) Did you try disabling GPU acceleration ? Known to cause problems in vegas. Disable in the both main settings and export settings

    3) You can export another format (e.g uncompressed RGB avi) to check and rule out h264 issue , or RGB<=>YUV issue, vs. upstream vegas problem.
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  3. Member
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    I've experimented with doing the fade in various different ways, simple one layer, to the imaginations limit! Always the same.

    The h264 idea was a bit of a long shot

    Yeah I noticed the colour shifting, unfortunately I'm not knowledgeable enough to know what you're referring to when you say . . .

    Originally Posted by poisondeathray View Post
    a rec601 vs. rec709 issue
    [Though I've read up on it a bit now. It seems there is no end to the depths of video coding and colour gamut complexity and how it's going to mess with the desired simplicity of your video processing life]

    I read up on the YUV colour space a while back, so thought it may be linked to this, as there might be more green in the blue so therefore more degrees of colour or something like that.


    1)
    My goodness! When I re-import it (exported as Sony AVC with problem), it views fine in the preview!!! I was cynical about that and to my shame I almost didn't even bother trying. What could it mean?!
    I had already tried viewing it in the Quicktime Player, and had uploaded it to YouTube (for another reason) and in both I still had the problem.

    2)
    I tried disabling GPU acc, in export/render settings, and I think I found where it was in the main settings and disabled it there too. I went to options on the main menu - preferences on the drop down - 'video' tab on the newly opened window - then selected 'off' on the drop down for 'GPU acceleration of video processing' though this was already selected.

    3)
    OK, I'm starting to feel lazy/incompetent now. I tried exporting/rendering using different codecs/methods . . .

    Video for Windows - uncompressed RGB = fine
    MainConcept AVC = problem
    Sony AVC = problem
    Video for Windows - Intel IYUV = fine
    Video for Windows - Sony YUV = problem

    Is Sony video coding the problem do you think? I think that Sony acquired MainConcept, so it's sort of still Sony.

    I previously had this idea of trying different codecs/exports, but didn't go through with it, because of the time of rendering (I shortened the rendering/export section further to nothing but the problem fade) and to be honest, a bit of laziness and the hope of finding someone like you on a forum!

    I think really my progressively lowering opinion of Sony/Magix Vegas/Movie Studio was the reason why I didn't continue experimenting. I thought someone might just post a comment saying 'nothing you can do, Sony is rubbish'. I had previously been having problems using certain fonts in Sony Vegas/MS media generator which there was no real solution to. I wrote to Sony/Magix and they said it would be resolved in a future update


    I wasn't holding much hope for a useful response in a forum, especially such a quick response, but you have proved me wrong (or the internet has, but I don't want to de-humanise you). I already owe you a beer or something. Though the problem isn't completely solved, there is definitely enough light now to see how one might arrange a work around.
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  4. Uncompressed RGB test indicates no upstream problems (ie. to rule some issue with the way you setup the project, or problem importing or interpeting assets before encoding, or timing issue if you had multiple layers controlling the fade)

    Re-import of Sony AVC/mp4 test suggests export is actually fine, and that your problems are from your display configuration setup on VLC, Quicktime, YT, etc...

    Were all these tests and observations using 1920x1080 ?

    Those observations suggest it is YUV<=>RGB using wrong matrix (ie. 709/601 mismatch) on playback; or at least that's a contributing factor

    Some of the playback chain you might not be able to fully control (e.g youtube) . But HD should look right on youtube - so something is wrong if the HD version (720 and up didn't look right). It uses 709 for HD and SD, so SD should look incorrect . But sometimes if you have GPU on vs. off for web acceleration it can make a difference, or if you're using HTML5 vs. flash. And you should realize you cannot control what end users have configured for playback - the best you can do is produce proper or "correct" video . 709 is standard for HD , 601 is standard for SD.

    Basically you have to configure and fiddle with GPU settings, software settings, drivers, renderer. For each display pathway. It's better to use a test chart / known colors and do it systematically
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