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  1. I know 1080p 23.976 and 24fps is Bluray compliant but what about 1080p 25fps or 29.97fps?

    I thought there are BBC Blurays in 1080p 25fps or am I wrong?

    I've taped BBC Live at the Apollo in 1080i. I read somewhere that they actually film in 25fps progressive or perhaps it's 50fps progressive? I re-encoded to 1080p 25fps and the frame rate looks fine (not juddery). So does that mean it was indeed filmed in 25fps progressive or 50fps progressive?

    What about 576p 25fps? Is that supported?
    Last edited by MrBiggles; 3rd Oct 2015 at 19:03.
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  2. Thanks. I'm aware of that table but it's not a complete table of everything that's compliant.
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  3. Originally Posted by MrBiggles View Post
    Thanks. I'm aware of that table but it's not a complete table of everything that's compliant.
    Then how about this:

    https://www.videohelp.com/hd

    To answer your question, no, 1080p 25fps or 29.97fps aren't compliant. The content may be progressive but has to be encoded as interlaced.
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  4. Sorry, double post.
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    Specifically it is PsF encoding which can make 576p 25fps and 1080p 25fps or 29.97fps playable on authored Blu-Ray. PsF allows the player to treat the video as interlaced, but when displayed it appears to be progressive.
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  6. OK thanks. Any idea how to do a PSF encoding in x264. I'm using AviSynth as well.

    Does anyone know what frame rate BBC Blurays of TV series are in? I assume they're 1080p but what framerate?
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  7. A quick search of their site would get you this: Our Blu-ray discs are authored to UK 50i specs.
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    Originally Posted by MrBiggles View Post
    OK thanks. Any idea how to do a PSF encoding in x264. I'm using AviSynth as well.
    I did a search using Google and found a thread at creativecow.net which said to use x264's free command line version with with --fake-interlaced and --bluray-compat

    [Edit] you also need to use --pic-struct doom9 has additional information here
    Last edited by usually_quiet; 4th Oct 2015 at 12:53. Reason: creativecow link is to a thread not a post added information from doom9
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  9. You can encode interlaced with --tff or --bff.
    Last edited by jagabo; 4th Oct 2015 at 12:06.
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  10. Jagabo I know I could encode as interlaced with --tff however that will actually interlace the video which I don't want. I was of the understanding that --fake-interlaced basically just tells the Bluray player to treat it as interlaced but the video will remain progressive?
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    Originally Posted by MrBiggles View Post
    I was of the understanding that --fake-interlaced basically just tells the Bluray player to treat it as interlaced but the video will remain progressive?
    I remember seeing PsF described as an alternate method for storing progressive video where complete frames are stored in two segments. One segment contains the even lines and the other contains the odd lines. These two segments are not the same as interlaced fields because they represent the same point in time, but can be treated like fields by equipment designed to work with interlaced video.
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  12. Originally Posted by MrBiggles View Post
    Jagabo I know I could encode as interlaced with --tff however that will actually interlace the video which I don't want. I was of the understanding that --fake-interlaced basically just tells the Bluray player to treat it as interlaced but the video will remain progressive?
    --tff doesn't interlace the content. It tells the encoder to use MBAFF encoding. The content will still be progressive either way. Content and type of encoding are 2 different things.
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  13. http://www.x264bluray.com/home/1080i-p

    Everything is there if you follow and read the post linked by imhh1...
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    What if any advantages does encoding using --tff (or bff) offer compared to encoding with --fake-interlaced? Is one preferable to the other under some circumstances?
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  15. Originally Posted by usually_quiet View Post
    What if any advantages does encoding using --tff (or bff) offer compared to encoding with --fake-interlaced? Is one preferable to the other under some circumstances?
    No advantage in terms of quality . For progressive content, progressive encoding is always better in terms of quality: progressive > MBAFF > PAFF . --fake-interlaced uses progressive encoding. x264 doesn't use PAFF

    Hypothetically, --fake-interlaced might give problems with some authoring tools, but I haven't see any that doesn't have problems with MBAFF in the first place (even though it's progressive encoding, just "flagged" MBAFF) (e.g. DVDA)

    Hypothetically, a certain hardware setup might wrongly deinterlace --fake interlaced, or MBAFF, causing lower quality. But it would do the same for both. (A way around that to ensure progressive handling in is to slow down both video & audio to "24p", even in 50Hz areas)

    So I can't think of any circumstance that you would not use --fake-interlaced for the 1920x1080p25 case
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  16. Is there a way to get 576p 50fps videos to be compliant?
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  17. Originally Posted by MrBiggles View Post
    Is there a way to get 576p 50fps videos to be compliant?
    No.

    You would either convert it to interlaced 720x576 (50 fields/s to keep the motion fluidity), or upscale to 1280x720p50
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