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  1. I'm making 720p 50fps and 1080i 25fps Blurays. They are under 10 Mbps bitrate.

    Can someone please tell me what the following means:
    1.2.1 Primary Video Rules
    http://forum.doom9.org/showthread.php?t=154533

    How do I know which level to use 4.0 or 4.1?
    How do I know which Max Allowed Bitrate to use?

    I looked at this column "Max bitrate for BD (2 sec GOP allowed)". How do I know if I'm using a 1 or 2 sec GOP? Where is the switch that tells the program what length of GOP to use?

    What are the Max Ref Frames and what switch do I use for that?

    What are the following columns:

    Max Frames in 1 sec/2 sec GOP? What switch can I use to set the max frames in 1/2 sec GOP?
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    For the 1080i case, 2sec gop means --keyint 50 for you. 1 sec at 25 frames/s is 25 frames. So 2 seconds is 50 frames. Similarly for the 720p50 case it would be --keyint 100 for 2sec gop

    2sec gop rules for BD means L4.0 , don't need 4 slices. But maxrate is limited --vbv-maxrate 15000 --vbv-bufsize 15000. So why would you want to do this? Because it's more efficient. Quality will be higher at equivalent low range bitrates. 2sec gop means you can "stuff" more low cost b-frames. More slices slightly reduce efficiency as well. So this only works your goal is < 15Mb/s

    Otherwise for higher bitrate BD, stick to "standard" 1sec gop rules, which are L4.1, 4slices , maxrate of 40000
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    drag your file in Multiavchd. Non compliant file will appear in red.
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  4. Originally Posted by imhh1 View Post
    drag your file in Multiavchd. Non compliant file will appear in red.
    It only does that if it's an unsupported resolution or codec, etc. The video could still have non-compliant stuff like is being discussed in this thread.

    Poisondeathray - I'm looking at the table but I don't understand how you said if using 2 sec GOP you need L4.0? Is that because the max bitrate will be under 24,000 which means you need L4.0?

    The table says the max buffer size for BD should be 30,000 regardless of the other settings but you said 15,000. Which is correct?
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    If you choose to use "2 sec GOP rules", you must use L4.0, 15,000 (--vbv-maxrate 15000 --vbv-bufsize 15000). It's not clear on the chart

    Read the column in RED "Max bitrate with 2 sec GOP allowed". The table doesn't show it, but it should be the same value for the buffer . Those are max values, but only under certain conditions. Basically, you're only allowed to have a 1sec buffer in BD. Read the section on buffer. A buffer of 30000, and maxrate of 15000 means 2 seconds when the buffer is full (illegal)

    If it's too confusing for you the take home message is: (of course "newer" should be "never", typo by shon3i)
    Basicly vbv-bufsize should newer been greater than vbv-maxrate, that is whole point.


    RE: multiavchd - it hasn't been updated in a few years , and doesn't check for strict BD compliance (it will allow some things pass that shouldn't). And if it has to re-encode, it doesn't use the newer x264 compliant BD builds , and you can't just drop in a new x264.exe because the API core has changed (There are a bunch of new switches, you would have to get Dean to update the GUI)
    Last edited by poisondeathray; 19th Jul 2014 at 10:29.
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    At the bottom of that doom9 post are several links to x264 coding examples using numbers from those tables. The main start page for that x264 encoding guide is here http://www.x264bluray.com/home .

    I guess using TMPGEnc Mastering Works most of the time is making me lazy about these settings. Depending on the BD output structure you request, most of the "max" settings are already there in TVMW5's dialogs. Most of the time I use 1-sec GOP's for BD and AVCHD. In the French racing example I posted in an earlier thread, I believe I used a GOP of 11 for fast action with low bitrates and the slowest VBR encoding available.
    -ann's brother
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  7. Thanks. I noticed this description:

    --open-gop

    Use non-IDR pictures instead classic IDR picture, this will tend to resolve pulsing picture problem that is usually came with short GOPs.
    How do I know if I've to use that switch or not?

    What settings would you recommend for 720p 25fps 4 Mbps videos? I understand those aren't compliant but there's switches to make it work.
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    IF you expect to do any edits/cuts on the encoded results, most nle's require closed GOP's. Otherwise it's as the description explains, to prevent pulsing playback problems with short GOP's. If you don't see that problem, forget about that switch.
    -ann's brother
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  9. Yes but what is defined as a short GOP? 1 sec, 2 sec?
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    --open-gop

    Use non-IDR pictures instead classic IDR picture, this will tend to resolve pulsing picture problem that is usually came with short GOPs.
    How do I know if I've to use that switch or not?
    Strictly speaking, --open-gop is compliant for BD (when used with --bluray-compat, x264 uses a special open gop mode to ensure compatiblity), and it helps slightly with compression efficiency. But it can cause problems with some authoring programs. My opinion, the benefit isn't worth the potential headache

    And it's a bad description , because it doesn't really resolve "pulsing" picture problem. That is more from low IDR quantizer in comparison to B,P frames ("I" frames are usually high bitrate, higher quality, so there can be a flutter or pulse as you transition between frametypes). Default ipratio is 1.4, pbratio is 1.3 - If you adjust I:P, B:P ratios closer to 1 (maybe 1.1, 1.2), that will have more effect on pulsing problem if your content predisposes you to it. But note pbratio is disabled when you use mbtree (if you disable mbtree you have control over both)


    Yes but what is defined as a short GOP? 1 sec, 2 sec?
    In BD, there are only 1sec GOP rules, 2sec GOP rules. That's it.

    But in the larger context, those are both considered shorter GOP's because "normal" compression for everyday use , will have about 10sec GOP (--keyint 250 for 25fps)
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  11. Thanks. MeGui has the following settings enabled:
    Force key frames for chapter marks. Should I have that enabled?

    MeGUI has the following options for AVC Profile: Baseline, Main or High. The Doom9 page doesn't mention anything about the Profile. Which should I choose?

    Any idea how I can find out the color characteristics (i.e BT 709) of a video if MediaInfo doesn't say what it is?
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    Originally Posted by VideoFanatic View Post
    Thanks. MeGui has the following settings enabled:
    Force key frames for chapter marks. Should I have that enabled?
    I think so. I'm guessing that it's using a qpfile to insert IDR frames at chapter marks . If you were using x264 manually, that's what you would be doing. That's good, otherwise navigation by chapters might not be accurate .


    MeGUI has the following options for AVC Profile: Baseline, Main or High. The Doom9 page doesn't mention anything about the Profile. Which should I choose?
    High



    Any idea how I can find out the color characteristics (i.e BT 709) of a video if MediaInfo doesn't say what it is?
    By convention BT709 is used for HD . Note "--colorprim bt709 --transfer bt709 --colormatrix bt709" doesn't actually change anything except VUI information (it's just metadata). The actual video isn't changed
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    Originally Posted by poisondeathray View Post
    --open-gop

    Use non-IDR pictures instead classic IDR picture, this will tend to resolve pulsing picture problem that is usually came with short GOPs.
    How do I know if I've to use that switch or not?
    And it's a bad description , because it doesn't really resolve "pulsing" picture problem. That is more from low IDR quantizer in comparison to B,P frames ("I" frames are usually high bitrate, higher quality, so there can be a flutter or pulse as you transition between frametypes). Default ipratio is 1.4, pbratio is 1.3 - If you adjust I:P, B:P ratios closer to 1 (maybe 1.1, 1.2), that will have more effect on pulsing problem if your content predisposes you to it. But note pbratio is disabled when you use mbtree (if you disable mbtree you have control over both)
    That's new info I hadn't seen. Thanks for the details.
    -ann's brother
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  14. Are you sure? My 1080i video copied from my satellite box says in MediaInfo that the "Color Primaries" are BT.601

    Any idea how I can find out the color characteristics (i.e BT 709) of a video if MediaInfo doesn't say what it is?

    What Avisynth script would I use to get BT 709?
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    Originally Posted by VideoFanatic View Post
    Are you sure? My 1080i video copied from my satellite box says in MediaInfo that the "Color Primaries" are BT.601

    Any idea how I can find out the color characteristics (i.e BT 709) of a video if MediaInfo doesn't say what it is?

    What Avisynth script would I use to get BT 709?
    Yes, I'm sure.

    Again, these are just metadata flags. If you leave no flags, the stream will not be changed. If you use flags, the stream will still be unchanged. It has nothing to do with the actual YUV video data

    Even if mediainfo said BT.VideoFanatic or BT.Poisondeathray, that says nothing about the actual video content . ie. It's just a "label." If you encoded with --colormatrix bt709 it will look the same as if you encoded with --colormatrix bt470bg . It does not affect the actual encoding.

    And on the display side - very few mediaplayers and even fewer hardware players actually read those flags . Test it out yourself. Encode with with 709, one with something else. It will look exactly the same on a BD player

    However, if you make a change in avisynth with colormatrix (some settings), then yes, the actual video can be changed.

    The difference between BT601 / 709 generally refers to RGB<=>YUV conversions. If you want to keep the same quality, don' t convert to RGB and back to YUV. Don't change anything. It supposed to refer to the lineage of the video. e.g. The studio master is in RGB (e.g. filmscans, digital intermedates), then is converted to a YUV intermediate with a 709 matrix, then finally encoded to blu-ray for distribution. That metadata is supposed to be indicating you what was done previously. But often the metadata isn't necessarily correct either, or it 's flagged incorrectly.
    Last edited by poisondeathray; 19th Jul 2014 at 13:52.
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    I just want to add that DVDA likes half-sec GOP, unless the bitrate is very low. If you won't be using DVDA, then don't worry about it.
    The memories of a man in his old age, are the deeds of the man in his prime.......
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    When you view your "original" in any current software mediaplayer, HD videos will be using 709 matrix to convert to RGB for display. Most software mediaplayers will base the distinction on HD vs. SD, as per convention . They typically use 709 for HD, 601 for SD. The only flag reader setup currently available is MadVR renderer with some mediaplayers, and you have to set it up correctly

    If you want to see what it looks like under 601 vs 709, you can check in avisynth with ConvertToRGB(matrix="Rec601", interlaced=??) , or ConvertToRGB(matrix="Rec709", interlaced=??)

    If you feel that the RGB conversion for display using 601 looks more correct, then that would be a case to use colormatrix to correct for it in avisynth (that changes the actual YUV video data)
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  18. Thanks for all your help. Did all the switches and the video came out fine. Noticed "ReFrames: 5 frames" mentioned in MediaInfo. What's that?

    So these are the switches I'm using:

    Code:
    --crf 17 --preset veryfast --sar 1:1 --bluray-compat --vbv-maxrate 15000 
    --vbv-bufsize 15000 --profile high --level 4.0 --keyint 100 --slices 1
    Is there anything else I can do to lower the file size?
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    mediainfo doesn't report reference frames correctly, it reads the dpb size. So if you have bframes or bpyramid it will change the number.

    The encode log or x264 encode string settings will report the correct number, but you should be entering --ref explicitly anyways. For 720p50 you can use up to 6. The higher the number , the potentially better efficiency , but the slower the encode

    To lower the size you can use a higher CRF. But should really be using 2 passes for BD because you have fixed capacity. Use a better preset as well. You will get better results.
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  20. Hi, I have remux MKV file to Bluray ISO using tsmuxer and burned them to bluray disc using Imgburn.
    However, my new sony and lg bluray player won't play the disc but my older sony bluray player plays the disc but with incorrect aspect ratio.
    the original display should be 2:35 but it has converted to 1:85. The original file contained the MKV File with pgs subs, the subs can be displayed
    correctly. My questions are :-
    (1) why the new bluray player refuse to play this disc? and
    (2) why the aspect ratio is incorrect despite that i have remux the MKV file with MKVTools.
    (3) it is possible to burn more than 1 movies with the Bluray ISO and how?

    Thanks for reply.
    Lee
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  21. Start your own thread please.

    1. Don't know for sure but maybe because it's not compliant to the Bluray spec. See post 18 for the settings you need to make a HD video compliant. Try re-encoding a 1 minute clip of your video with the settings mentioned. Then author to Bluray and see if it works. I don't think TSmuxer produces a compliant Bluray. MultiAVCHD isn't fully compliant either but it should work - it muxes intead of re-encoding..

    2. Video should be encoded with a Signal Aspect Ratio of 1:1 as mentioned in the settings in my post assuming it's HD footage.

    3. Of course. ImgBurn > Mode > EZ Mode Picker > Write Image file to disc.

    What resolution, framerate and audio codec and audio bitrate is used? AAC can't be used, only LPCM, Dolby or DTS
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  22. Thanks a lot for your reply.
    May I ask why my older Sony and Philips bluray disc player can play the disc but not the newer player?
    The problem for the older player is only the aspect ratio glitch. The newer player (2 players with different brand)) can load the disc but it will reject the disc after loading.
    Thanks.
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  23. Was wondering what the --bluray-compat switch does. Is THIS what it does?:

    In particular is "max references to: 6 or less" the same thing as "Max Ref Frames" in the 2nd table HERE?
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    tsmuxer does not enforce compliance or convert non-compliant audio/video input. It's quite possible to use it to create BluRay or AVCHD discs that violate the standards. Some players are more flexible than others. The newer player may be insisting that BluRay video be exactly 1920x1080 and your video may be something different like 1920x880. Sony players are all over the map with some players at some point playing almost nothing that's not perfectly in spec and others sometimes being very flexible and playing anything close, to spec but not exact. You can specify the aspect ratio in tsmuxer. I don't know anything about your input, but if for example you live in the USA and your input video has 25 frames per second, a lot of US sold BluRay players may refuse to play that as they're expecting 24 or 29.97 or 60 frames per second depending on the resolution of the video. Could be a lot of possible problems here. If you want to open the original MKV with MediaInfo and post the details here, we can examine it for things that might be a problem.
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  25. Can anyone help with this please:

    Was wondering what the --bluray-compat switch does. Is THIS what it does?:

    In particular is "max references to: 6 or less" the same thing as "Max Ref Frames" in the 2nd table HERE?
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    Originally Posted by VideoFanatic View Post
    Can anyone help with this please:

    Was wondering what the --bluray-compat switch does. Is THIS what it does?:

    In particular is "max references to: 6 or less" the same thing as "Max Ref Frames" in the 2nd table HERE?
    Yes
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  27. Thanks, is that yes to both questions?
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    Originally Posted by VideoFanatic View Post
    Thanks, is that yes to both questions?
    Yes

    What is your concern ?
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