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  1. Member
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    There's been a lot of discussion in my other thread regarding encodes done @ 23.976 vs 24. One thing that always confused me is why you'd use 23.976/24 if NTSC DVD is 29.97fps. That's why I always made the mistake of encoding @ 29.97. But it just hit me. I had de-telecine engaged when I did. So if I understand this correctly now, telecine is the process that takes a native 23.976/24 source and converts it to 29.97 for NTSC DVD right? So if you have de-telecine selected, it reverts the DVD back to its original source of 23.976/24. But..would 29.97 have worked if I had de-telecine turned off?

    Finally, I was encoding Luther recently (great show on the BBC network) and I came across an anomaly. Both 24 and 23.976 didn't work. So when I turned on same as source to find out the frame rate, it told me that it was 29.97. The weird thing is that when I encoded @ 29.97 manually to match, playback was still off. The magic frame rate ended up being 59.94. Is this because it is a progressive derivative of 29.97 and would get better playback on an HDTV?
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  2. Originally Posted by rdeffley View Post
    So if I understand this correctly now, telecine is the process that takes a native 23.976/24 source and converts it to 29.97 for NTSC DVD right? So if you have de-telecine selected, it reverts the DVD back to its original source of 23.976/24. But..would 29.97 have worked if I had de-telecine turned off?
    Yes. It would have encoded it as 29.97, progressive. Which would be wrong - you will have every 5th frame repeated, jerky playback moreso than the "normal" 3:2 judder

    Finally, I was encoding Luther recently (great show on the BBC network) and I came across an anomaly. Both 24 and 23.976 didn't work. So when I turned on same as source to find out the frame rate, it told me that it was 29.97. The weird thing is that when I encoded @ 29.97 manually to match, playback was still off. The magic frame rate ended up being 59.94. Is this because it is a progressive derivative of 29.97 and would get better playback on an HDTV?
    From a NTSC DVD source? For a BBC show, likely it should be 25 for the original source, and there might be other problems such as field blending because of the conversion to NTSC. You can upload a sample if you want someone to look at it
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    Yep, I thought the same thing. When 23.976 and 24 both resulted in choppy playback, I did a test @ 25fps because it is a UK based show. However, even though playback improved somewhat, it still looked unnatural and jolty. That's when I did a same as source test to get the frame rate and it's 29.97. Took the Video TS folder into VLC and there was some blending and interlacing issues. So I'm guessing there was an encoding snafu on their end.

    Regardless though, the end results look great. Even though episodes are 58-60 min long as opposed to standard 40-45 min of US programming, file sizes were still relatively small @ 600-650mb's. Final output was 624x352/59.94 fps @ constant quality of 17.75.
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  4. If VLC wasn't on "blend deinterlace", and you saw blends, then likely there was a blend conversion being done

    The other option is to attempt to deblend it properly and restore it to the original rate in avisynth . 25 fps might look "jolty" in handbrake because it's probably dropping the wrong frames

    A deblended, 25fps version will compress better and take up even less room for "similar quality" than a 59.94 fps version, since you have fewer than 1/2 the frames (it won't be 50-60% smaller, that's not how temporal compression works, but it will compress better for sure)
    Last edited by poisondeathray; 4th Jan 2015 at 19:42.
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    I don't have any experience with avisynth but I'm guessing from the name it outputs AVI files? Just have never been a fan of that format. It's funny though. When I did tests with 23.976, 24, 25, and 29.97, the file size was only 50-60mb's smaller. Since I've got six 2TB drives running through my PC (hooked into my 1080p Samsung LED), I'm not gonna quibble over it. Of course it all comes down to personal standards. But for me, this is what I prefer :

    SD DVD TV eps (42-47 mins) : 350-500mb's
    SD DVD full length movies : 1.2-1.5gb's (For longer movies like The Abyss and True Lies I'll tolerate 2gb's)
    720p TV eps : 550 (if the source is really nice) -750mb's.
    720p full length movies 2-3gb's.

    ** I don't encode in 1080p because the difference is minimal for the amount of extra drive space IMO

    Whenever I've seen encodes designed to save a lot of drive space - 600-700mb movies, YIFY's so called "720/1080p", etc they look and sound like crap. I've probably only seen a handful of SD 700mb movie encodes that looked truly good. But I want to give a shout out to two encoders. Anoxmous puts out transparent 1080p @ 1.8-3gb's a movie. The guy is a genius with MeGUI. I've done comparisons between an 8-10gb 1080p and his, and there is no difference. The other is a guy named DeeJay Ahmed. He puts out REALLY nice looking 350-400mb 720p TV show episodes.
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  6. Originally Posted by rdeffley View Post
    I don't have any experience with avisynth but I'm guessing from the name it outputs AVI files? Just have never been a fan of that format. It's funny though. When I did tests with 23.976, 24, 25, and 29.97, the file size was only 50-60mb's smaller. Since I've got six 2TB drives running through my PC (hooked into my 1080p Samsung LED), I'm not gonna quibble over it. Of course it all comes down to personal standards. But for me, this is what I prefer :

    SD DVD TV eps (42-47 mins) : 350-500mb's
    SD DVD full length movies : 1.2-1.5gb's (For longer movies like The Abyss and True Lies I'll tolerate 2gb's)
    720p TV eps : 550 (if the source is really nice) -750mb's.
    720p full length movies 2-3gb's.

    ** I don't encode in 1080p because the difference is minimal for the amount of extra drive space IMO

    Whenever I've seen encodes designed to save a lot of drive space - 600-700mb movies, YIFY's so called "720/1080p", etc they look and sound like crap. I've probably only seen a handful of SD 700mb movie encodes that looked truly good. But I want to give a shout out to two encoders. Anoxmous puts out transparent 1080p @ 1.8-3gb's a movie. The guy is a genius with MeGUI. I've done comparisons between an 8-10gb 1080p and his, and there is no difference. The other is a guy named DeeJay Ahmed. He puts out REALLY nice looking 350-400mb 720p TV show episodes.




    Avisynth is what those "genius" guys you're talking about are using. It doesn't have to output AVI, but it can. It's just a frameserver, and processing tool - it frameserves uncompressed audio & video so you can encode to any format

    If quality is important to you , you'll probably want to deblend it. Blurry strobey frames ? or close to original clean frames ? It's no contest

    If you can't see the difference between a 3GB 1080p version and the same video as a 9GB video (3x the bitrate), either the 9GB was very poorly done, or you need another method of comparison and your eyes checked
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  7. Originally Posted by rdeffley View Post
    So I'm guessing there was an encoding snafu on their end.
    No, all BBC material on NTSC DVD uses field blending to do the conversion from PAL. It's horrible.

    Originally Posted by rdeffley View Post
    I don't have any experience with avisynth but I'm guessing from the name it outputs AVI files?
    It outputs whatever you like, depending on the encoder you're using. But you can't use Handbrake for the job. In any event, if you want to reencode BBC sources and get decent results, you'll have to learn how to unblend using AviSynth and forget about Handbrake.
    But I want to give a shout out to two encoders.
    Nobody cares.
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    Is Avisynth an actual encoding program, or is it used for script writing in tandem with another program? Based on the little research that I've done, it looks like VirtualDub is also used? I used VirtualDub way back in the day but it's been awhile.
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  9. AviSynth is a filtering and frame serving program. It only outputs uncompressed video frames to an editor or encoder. The editor/encoder determines what codecs and containers the final video uses.
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    So you'd take the VOB files into AviSynth, export uncompressed out of there, and then take that into an encoding program?

    Also, I tried installing Avisynth on my computer and nothing showed up. When I went to the folder in Program Files (x86) all it had it in was folders for "docs". "examples", "license translations" "plug ins" and a few txt files. There is no program application to click on, and nothing went to my desktop when I installed.
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  11. You create an AviSynth script (plain text, Notepad will work) that imports the source video then filters it. The script should end with the extension .AVS:

    Code:
    Mpeg2Source("filename.d2v") # anything after a hash mark is a comment for the user
    TFM() # field matching
    TDecimate() # decimation to 23.976 fps
    You then open that script as if it was a video file in an editor/encoder that supports AviSynth.

    http://avisynth.nl/index.php/Main_Page#New_to_AviSynth_-_start_here

    The main "program" in AviSynth is a dll file, avisynth.dll, that's installed in Window's system folder. It's invoked automatically when a video editor imports the AviSynth script as a video. I recommend you use VirtualDub to view the video output of your AviSynth script (File -> Open Video File...). Or you can use avspmod which has a bunch of helper functions for creating/editing/visualizing AviSynth scripts.

    To remove field blending from PAL/NTSC conversions you'll need to download and install a bunch of other third party filters. Including SRestore(), QTGMC(), TFM(), TDecimate(). Etc.

    http://avisynth.nl/index.php/External_filters
    http://avisynth.nl/index.php/QTGMC
    http://avisynth.nl/index.php/Srestore
    http://avisynth.nl/index.php/TIVTC/TDecimate

    Yes, it's a big pain getting it set up. But it's the most powerful video filtering tool and the only way to remove field blending from PAL/NTSC conversions.

    Code:
    Mpeg2Source("filename.d2v") # field blended source
    QTGMC(preset="fast") # smart bob, faster possibilities: Yadif(mode=1), or Interleave(TFM(field=0), TFM(field=1))
    SRestore() # remove field blends, restore original film frame rate
    Last edited by jagabo; 4th Jan 2015 at 23:38.
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  12. Member
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    Thanks for all the help with this! I'll mess around with it when I get some time.

    Update on Luther :

    1) Seasons 1 and 2 had a source frame rate of 29.97 as previously mentioned. But just for the hell of it, I did a test encode with "same as source" left on and it was the FIRST time I've ever seen smooth playback. In all other cases, same as source always resulted in choppy playback and manually selecting the frame rate gives the best playback. Yet another anomaly.

    2) Season 3 had a source frame rate of 23.976 and PQ on the DVD's was definitely better than the DVD's for S1 and S2. I'm curious as to why the other two seasons didn't have frame rate of 23.976. All other NTSC DVD's I've come across do. Maybe the first two seasons of Luther weren't shot on film? If video was used, it might explain the 29.97 frame rate.
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  13. Originally Posted by rdeffley View Post
    2) Season 3 had a source frame rate of 23.976 and PQ on the DVD's was definitely better than the DVD's for S1 and S2..
    All NTSC DVDs output interlaced 29.97fps, so I'm not sure where the 23.976fps comes from. Maybe they were soft telecined. If true, then even Handbrake can handle them. Anyway, short samples are always useful to help determine what you have.
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