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  1. Everything I say is false koberulz's Avatar
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    Originally Posted by DB83 View Post
    Why ?


    Because you have not proved, to me atleast, why you need to waste your time doing this.
    Why on earth would you think I need to?
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  2. Member DB83's Avatar
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    Bottom line. You do not have to.


    The general consensus is that PAL speed-up is not-detectable (unless your own hearing is acute)


    But I also do not want to see a post down the line when you have made a general assumption and 'ruined' your original.


    Unless you wish to read 'Told you so'


    But I will leave the thread now (unless you wish to continue the vitrol)
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  3. Everything I say is false koberulz's Avatar
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    So this was all going swimmingly until season six, at which point something went really wonky with the encoding settings.

    Seasons 1-5:
    Code:
    Video
    ID                                       : 1
    Format                                   : AVC
    Format/Info                              : Advanced Video Codec
    Format profile                           : High@L3
    Format settings, CABAC                   : Yes
    Format settings, ReFrames                : 5 frames
    Codec ID                                 : V_MPEG4/ISO/AVC
    Duration                                 : 48 min 19 s
    Width                                    : 720 pixels
    Height                                   : 576 pixels
    Display aspect ratio                     : 16:9
    Frame rate mode                          : Constant
    Frame rate                               : 23.976 (24000/1001) FPS
    Color space                              : YUV
    Chroma subsampling                       : 4:2:0
    Bit depth                                : 8 bits
    Scan type                                : Progressive
    Writing library                          : Lavc58.54.100 libx264
    Default                                  : Yes
    Forced                                   : No
    DURATION                                 : 00:48:19.397000000
    Season six:
    Code:
    Video
    ID                                       : 1
    Format                                   : AVC
    Format/Info                              : Advanced Video Codec
    Format profile                           : High@L3
    Format settings, CABAC                   : Yes
    Format settings, ReFrames                : 5 frames
    Codec ID                                 : V_MPEG4/ISO/AVC
    Duration                                 : 42 min 55 s
    Bit rate                                 : 1 344 kb/s
    Width                                    : 720 pixels
    Height                                   : 576 pixels
    Display aspect ratio                     : 16:9
    Frame rate mode                          : Constant
    Frame rate                               : 23.976 (24000/1001) FPS
    Color space                              : YUV
    Chroma subsampling                       : 4:2:0
    Bit depth                                : 8 bits
    Scan type                                : Progressive
    Bits/(Pixel*Frame)                       : 0.135
    Stream size                              : 413 MiB (48%)
    Writing library                          : x264 core 159
    Encoding settings                        : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=8 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc=cqp / mbtree=0 / qp=20 / ip_ratio=1.40 / pb_ratio=1.30 / aq=0
    Default                                  : Yes
    Forced                                   : No
    DURATION                                 : 00:42:55.490000000
    WTF is going on? It's exactly the same batch file, I've been cutting and pasting it from one season folder to another as I go along, and yet all of a sudden it's used completely different encoding settings.
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  4. What's your ffmpeg command line? S1-5 weren't using libx264, S6 is.
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  5. Member DB83's Avatar
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    Sorry. But I have to ask. And it's a genuine concern.


    I did find the IMDB link (once I had cleaned my glasses). It states that the episodes were 44 minutes against the 41 that you have.


    So where does the 48 mins for series 1-5 come in ? (assuming you played one back and it is actually 48 mins). Series 6 does not appear to have altered.


    (Of course mediainfo calculates the runtime from file size and frame-rate)
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  6. Everything I say is false koberulz's Avatar
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    I grabbed that from the S5 premiere, which is longer than the other episodes. Possibly DVD-exclusive deleted scenes, or maybe that episode just ran longer. Nothing to worry about either way.

    Originally Posted by jagabo View Post
    What's your ffmpeg command line? S1-5 weren't using libx264, S6 is.
    Don't you mean the other way around? S6 is x264 core 159, the others are libx264. The batch file says libx264. I've just been cutting and pasting the batch file into each folder when I'm done with the previous season, so it can't have changed anyway.
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  7. My guess is you didn't specify the full path to ffmpeg.exe and in one case there is a copy of ffmpeg.exe in the current folder, in the other case there isn't -- so you're using a different build found somewhere in your search path.
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  8. Everything I say is false koberulz's Avatar
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    Code:
    ffmpeg\ffmpeg.exe -i script.avs -aspect 16:9 -acodec ac3 -strict -2 -vcodec libx264 -preset slow -qp 20 "Output\%%F"
    I've been copying the same ffmpeg folder into each season's folder as I work, too.
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    Originally Posted by DB83 View Post
    Bottom line. You do not have to.


    The general consensus is that PAL speed-up is not-detectable (unless your own hearing is acute)
    I HAVE to disagree with this. A more accurate statement would be that people in PAL-land have become completely desensitized to the speed-up and no longer even notice if it is or is not present. In NTSC parts of the world it is very much noticed as I can tell every single time when something is wrong.
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  10. Originally Posted by SaurusX View Post
    Originally Posted by DB83 View Post
    Bottom line. You do not have to.


    The general consensus is that PAL speed-up is not-detectable (unless your own hearing is acute)
    I HAVE to disagree with this. A more accurate statement would be that people in PAL-land have become completely desensitized to the speed-up and no longer even notice if it is or is not present. In NTSC parts of the world it is very much noticed as I can tell every single time when something is wrong.
    I agree. With actors and singers I know well I can usually hear the ~semitone increase in pitch. Though personally I don't care enough to bother fixing it.
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  11. Everything I say is false koberulz's Avatar
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    Any idea why my encoding settings are suddenly radically different, though?
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  12. You made a mistake somewhere.
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  13. Everything I say is false koberulz's Avatar
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    ...helpful.

    It's the same batch file and the same ffmpeg executable. So I'm not sure what variables could be involved here.
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  14. Originally Posted by koberulz View Post
    ...helpful.
    Jagabo does not deserve that snark. He's been nothing but helpful. You've been that way towards DB83 as well, actually even more so.

    I was going to make some suggestions, but I don't want to be the target of such comments. I will at least offer that jababo is on the right track because, when something has worked many times, and suddenly no longer works, it probably isn't because the software suddenly stopped working. Instead, either the new episodes are encoded differently, or something on your computer changed.

    The obvious first thing to try would be to copy one of the problem videos to the same location as a video that you were able to successfully modify and see if the new video, in the old location using the exact same setup also fails. The next step, without changing anything, is to re-do the video that is already in that folder. If the old video still works, but the new one doesn't, then it's the video. If they both work, then the suggestion that you have multiple ffmpeg builds is correct. If neither works, then something on your computer has changed, and you're going to have to figure that out yourself.
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  15. Everything I say is false koberulz's Avatar
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    How would the encoding of the originals affect ffmpeg? Since they're being re-encoded I wouldn't have thought that would make a difference?

    I don't even really understand what ffmpeg is actually doing differently in this case TBH. What are the writing libraries exactly?
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  16. ffmpeg includes lots of different decoders and encoders. At least 4 different h.264 encoders. Somehow you specified a different one. Plus, different builds might include different codecs and apply different metadata. I always use libx264 and get your second MediaInfo report with all the encoder settings in the metadata.
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  17. Everything I say is false koberulz's Avatar
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    But I've been copying the exact same files across....this makes no sense. Maybe my computer just hates me?
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  18. Everything I say is false koberulz's Avatar
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    Moved the S6 premiere into the S5 folder. Still encoding with x264 core 159.
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  19. Everything I say is false koberulz's Avatar
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    Tried the Pilot again....core 159 again. I have no idea why it was using libx264 before but refuses to now. What controls that?

    That aside...does it matter? I compared my two versions of the Pilot and the lib and core episodes look identical. Is there actually a difference between them? I thought S6 was dropping more quality than S1-5, but that might just have been what I looked at. Either way I'm thinking 20 is too high for a qp number, but even so.
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  20. You specified "--vcodec libx264" on the command line and it is using libx264 now. The metadata "Writing library : x264 core 159" is libx264. That is what I have always seen when using ffmpeg with that switch. It was using libx264 before as well, but through something that stamped the metadata "Lavc58.54.100 libx264". So both are using the x264 encoder.

    Another possibility is you are using a dynamic build of ffmpeg.exe and it picked up whatever avcodec dll it found first in the search path. Before that was a version that came with LAV filters, now it a version that came with ffmpeg (or something else).
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  21. Everything I say is false koberulz's Avatar
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    So....as I said, does it actually matter? I was thrown by the existence of a bitrate in the S6 MediaInfo, but it seems it's still using constant-quality encoding.

    Additional question: chapters. The original MKVs have them, is there a way I can convert them, time-wise, over to the new MKVs? I know how to use toolnix to insert them, but obviously the timestamps would be wrong.
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  22. I don't know much about chapter markers in ffmpeg.
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  23. Everything I say is false koberulz's Avatar
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    How is it that some episodes end up almost half the size of the originals, but others end up almost double? That makes no sense. I'd expect some to be bigger and some smaller, sure, but not by entire gigabytes on 43 minutes of SD video.

    Also, I checked a random episode and the audio is apparently 31.25fps, with a duration of 00:43:13.248 compared to the video's duration of 43:13.263. What's that about?
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  24. Originally Posted by koberulz View Post
    How is it that some episodes end up almost half the size of the originals, but others end up almost double?
    It makes perfect sense. And it's the reason constant quality encoding was invented. There's no way to know exactly how much bitrate a particular video needs. I typically see about a 2x difference in size between the smallest and largest episodes of a series encoded with crf encoding, even if they were all the same size as VOB.

    Originally Posted by koberulz View Post
    Also, I checked a random episode and the audio is apparently 31.25fps, with a duration of 00:43:13.248 compared to the video's duration of 43:13.263. What's that about?
    Don't worry about it unless the audio is out of sync.
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  25. Everything I say is false koberulz's Avatar
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    I was expecting smaller files, to be honest, given x264 is supposed to be much more efficient than MPEG2. One episode is smaller, the rest are around 1GB bigger, and there's still what looks like noise reduction resulting even at qp 16, which from my understanding is supposed to be around the "essentially lossless" threshold.
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  26. You're using qp=20, not very efficient. Try crf=18 or so.
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  27. Everything I say is false koberulz's Avatar
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    I thought qp and crf were the same thing? Is there a difference?

    MediaInfo is also reporting that my output video is variable frame rate.

    Regarding chapters, someone on reddit pointed me to mkvmerge's chapter_sync option, so I've now got this batch file:
    Code:
    for %%F in (*.mkv) do (
    echo A = LWLibAvVideoSource("%%F"^) > script.avs
    echo B = LWLibAvAudioSource("%%F"^) >> script.avs
    echo AudioDub(A,B^) >> script.avs
    echo AssumeFPS(24000,1001,sync_audio=true^) >> script.avs
    echo ResampleAudio(48000^) >> script.avs
    ffmpeg\ffmpeg.exe -i script.avs -aspect 16:9 -acodec ac3 -vcodec 
    
    libx264 -preset slow -qp 18 "Output\%%F"
    mkvextract "%%F" chapters "%%F.txt"
    mkvmerge -o "ChapterVersions\%%F" --chapter-sync 0,25/23.976 --chapters "%%F.txt" "Output\%%F"
    del "%%F.lwi"
    del script.avs
    del "%%F.txt"
    REM del "Output\%%F"
    )
    
    pause
    It works in the sense that the chapters in the resulting MKV have different timestamps to the chapters in the original MKV file, but they're still not at the same actual point in the episode. The last chapter occurs at 57:34.04 in the original (I'm using the Pilot to test, which is longer than a standard episode) and at 1:02:34.391304347 in the processed MKV. The episode itself only goes from being 1:03:24 to 1:06:06, so the chapter point shouldn't be moving by five minutes. It should be at almost exactly the one-hour mark.

    Is there a problem with the math?
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  28. qp and crf are different. qp is a mathematical constant quality. The same quantizer is used for each frame. crf takes into account what is more visible to the human eye. It uses different quantizers depending on the nature of the frame, motion, etc.

    Regarding chapter sync -- I don't know. Compare the chapter points one by one and see if the new values are the expected values. Chapter points may also need to coincide with keyframes.
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  29. Everything I say is false koberulz's Avatar
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    I'm not entirely sure what --chapter-sync is doing, to be perfectly honest.

    Original chapters:
    12:49.52
    22:43.44
    30:45.24
    49:32.16
    57:34.04

    New Chapters:
    13:56.434782608
    24:42.0
    33:25.69562173
    53:50.608695652
    1:02:34.391304347

    Expected new chapter points, approximately:
    13:22
    23:41
    32:04
    51:39
    01:00:00
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  30. It looks like the math is being done with integers, not floating point:

    12:49.52 * 25/23 = 13:56.43

    Try using "--chapter-sync 0,25.0/23.976024". If that doesn't work try "--chapter-sync 0,25000/23976".
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