Removing duplicate frames from YouTube 60fps to 23.976 fps

[AndersonJames]

I downloaded a video from YouTube and for some reason YouTube changed the FPS from 23.976fps to 60fps but all the extra frames are duplicates.
Why do they do that?

Is there any Avisynth script that will automatically remove the duplicate frames?

I tried the following. the FDecimate line works but the QTGMC line causes ghosting artifacts. Why does it do that and is there any way to use QTGMC without getting that problem as I want to remove the jaggies on the guy's glasses.

FDecimate()
QTGMC(Preset="Faster", InputType=1

Attached is the Untouched download via YouTube-DL program. Here's the batch script I used to download the video:

cd /D "%~dp0" 
youtube-dl -f ("bestvideo[width>=1920]"/bestvideo)+bestaudio/best https://www.youtube.com/watch?v=6CA9ilybJ5Q -o "L:/YouTube/Politics/%%(uploader)s/%%(upload_date)s    %%(title)s    %%(id)s    New Zealand %%(height)sp @@%%(vcodec)s %%(acodec)s@@. FPS %%(fps)s, Views %%(view_count)s.%%(ext)s" --embed-subs --sub-lang en --ignore-errors --restrict-filenames --download-archive archive.txt --merge-output-format mkv
youtube-dl https://www.youtube.com/watch?v=6CA9ilybJ5Q -o "L:/YouTube/Politics/%%(uploader)s/%%(upload_date)s    %%(title)s.%%(ext)s" --ignore-errors --restrict-filenames --write-description --write-thumbnail --skip-download 
PAUSE

Also attached is a shorter trimmed sample which I got by using the Trim tool in VideoRedo V5.

Script I'm Using

LWLibavVideoSource("L:\Trimmed VP9.mkv") 

SelectEven()
a=last

a
QTGMC(preset="Medium", inputtype=2, sharpness=0.5)
b=last

b.Trim(0,1272) ++ a.Trim(1273,0)

Even without the script after the SelectEven line, frame 0 and 1 are still duplicates and they shouldn't be. Seems that is causing QTGMC not to work, the script runs but QTGMC doesn't smooth the jaggies.

[poisondeathray]

Usually that would be the uploader's fault . If they uploaded 23.976p , youtube would keep it like that

If your assessment is correct, a possible script would look like

#Source Filter
SelectEven()
TDecimate()

[AndersonJames]

Thanks. The guy has over 800 thousand subscribers so I don't think the guy would upload a messy video like that. I think he uploaded in 23.976p. What do you think? His channel is here: https://www.youtube.com/c/TheQuartering/videos
Video is here: https://www.youtube.com/watch?v=6CA9ilybJ5Q

Do you have a link to a YouTube video which uses 23.976fps?

[poisondeathray]

Do you have a link to a YouTube video which uses 23.976fps?

eg. Almost any official movie preview/trailer

You can test it yourself. Upload a 23.976p video. No "59.94p" version will be even be offered


If he has a "60p" option , it means that's what he uploaded

[AndersonJames]

Usually that would be the uploader's fault . If they uploaded 23.976p , youtube would keep it like that

If your assessment is correct, a possible script would look like

#Source Filter
SelectEven()
TDecimate()

Tried that but it gives 25.808 fps instead of 23.976.

Tried this and FDecimate works but for some reason the QTGMC line adds weird ghosting artifacts. Why does it do that? I want to use QTGMC to get rid of the jaggies on his glasses. Any suggestions please? I've added a short clip of the source in my original post.

FDecimate()
QTGMC(Preset="Faster", InputType=1)

[poisondeathray]

Usually that would be the uploader's fault . If they uploaded 23.976p , youtube would keep it like that

If your assessment is correct, a possible script would look like

#Source Filter
SelectEven()
TDecimate()

Tried that but it gives 25.808 fps instead of 23.976.

Tried this and FDecimate works but for some reason the QTGMC line adds weird ghosting artifacts. Why does it do that? I want to use QTGMC to get rid of the jaggies on his glasses. Any suggestions please? I've added a short clip of the source in my original post.

FDecimate()
QTGMC(Preset="Faster", InputType=1)

Probably your source filter is not returning the proper frame rate , perhaps jitter in the timestamps. What are you using ?

Check with info() after the source filter , no other filters

[poisondeathray]

Video is here: https://www.youtube.com/watch?v=6CA9ilybJ5Q

That's 30.0p segment in that video with the face shot, and it's been badly deinterlaced and/or upscaled. Possibly some frame drops too. YOu can tell this because every 2nd frame is a duplicate in the 60.0p version

It's not 23.976p content



You can just download the 30.0p version, no processing. Or you can process it to "fix" the aliasing issues

[AndersonJames]

This is the source filter I'm using: FFVideoSource("L:\Trimmed VP9.mkv", fpsnum=24, fpsden=1, threads=1)

Info reports 64.5203 fps without using any other filters. Source Clip is attached in my first post.

[AndersonJames]

Video is here: https://www.youtube.com/watch?v=6CA9ilybJ5Q

That's 30.0p segment in that video with the face shot, and it's been badly deinterlaced and/or upscaled. Possibly some frame drops too. YOu can tell this because every 2nd frame is a duplicate in the 60.0p version

It's not 23.976p content



You can just download the 30.0p version, no processing. Or you can process it to "fix" the aliasing issues

Not possible normally for me to redownload the correct version as my download script always downloads the best quality version. Do you have a script to fix the video please?

[poisondeathray]

Not possible normally for me to redownload the correct version as my download script always downloads the best quality version. Do you have a script to fix the video please?

If you're starting with a 1080p60.0 version, it depends which version you downloaded- if you are using VP9 or H264.

I downloaded the AVC version with AAC audio using

youtube-dl -f 299+140 https://www.youtube.com/watch?v=6CA9ilybJ5Q

LWLibavVideoSource should be able to open either properly. You can check with info. It should say 60.0p

SelectEven will drop every 2nd frame, and you'll end up with 30.0p

Only the intro/closeup needs processing in terms of aliasing. The rest can be left at 30.0p (the latter part doesn't have the aliasing/jaggies issues)

LWLibavVideoSource("Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.mp4")
SelectEven()
a=last

a
QTGMC(inputtype=2, sharpness=0.5)
b=last

b.Trim(0,1272) ++ a.Trim(1273,0)

If you downladed a different version ,you might have adjust it slightly

[Dutchsteammachine]

I have found that the decimate filter in FFMPEG worked the best out of several other programs that I tried. Removed all duplicate frames.

[AndersonJames]

When I run that script it says:
Script error: There is no function named: LWLibavVideoSource

[AndersonJames]

Not possible normally for me to redownload the correct version as my download script always downloads the best quality version. Do you have a script to fix the video please?

If you're starting with a 1080p60.0 version, it depends which version you downloaded- if you are using VP9 or H264.

I downloaded the AVC version with AAC audio using

youtube-dl -f 299+140 https://www.youtube.com/watch?v=6CA9ilybJ5Q

LWLibavVideoSource should be able to open either properly. You can check with info. It should say 60.0p

SelectEven will drop every 2nd frame, and you'll end up with 30.0p

Only the intro/closeup needs processing in terms of aliasing. The rest can be left at 30.0p (the latter part doesn't have the aliasing/jaggies issues)

LWLibavVideoSource("Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.mp4")
SelectEven()
a=last

a
QTGMC(inputtype=2, sharpness=0.5)
b=last

b.Trim(0,1272) ++ a.Trim(1273,0)

If you downladed a different version ,you might have adjust it slightly

When I run that script it says:
Script error: There is no function named: LWLibavVideoSource

[poisondeathray]

When I run that script it says:
Script error: There is no function named: LWLibavVideoSource

LSmash
https://github.com/HolyWu/L-SMASH-Works/releases

[AndersonJames]

Thanks. Got it working. But when previewing the video in AvsPmod before encoding the video I can still see the ghosting. It's 30fps but there's still ghosting.

[poisondeathray]

Thanks. Got it working. But when previewing the video in AvsPmod before encoding the video I can still see the ghosting. It's 30fps but there's still ghosting.

What are you describing as "ghosting" ? Can you post a screenshot or describe it better?

I see motion blur, from the camera. It's soft , low quality upscale, blurry - but none of those are what would be described as "ghosting"

"ghosting" typically implies double images or after images. A blend of more than 1 time

[AndersonJames]

The following frames are duplicates: 15, 29
What does that mean?

I encoded the video but it came out looking much worse than the source. Frame 146 and 147 have an example of the ghosting I'm referring to. It looks like a previous image has had parts of it left behind in the current frame.


[Attachment 54200 - Click to enlarge]

QTGMC is actually make those artefacts, it's making the picture look worse rather than better! Any suggestions on how to fix the jaggies in the source?

[poisondeathray]

Something wrong with your version, maybe your dependency plugins are old ? If you comment out the QTGMC line, do you still get "ghosting"? (is it a lsmash issue or QTGMC issue on your end) ?

Are you using the original video? That frame 146,147 is nowhere near 146,147 in my version in 30fps

I don't see duplicates there on my version with that script in that range (did you mean 14,15, or 15,16) ? etc... either way in that range to frame 40 and beyond, each frame is unique for me .

I don't see any ghosting like that in mine either (QTGMC in progressive mode is helping the jaggies; or it does when you get it working properly)

[poisondeathray]

The corresponding screenshot for your screenshot should be frame 136

selecteven()

[Attachment 54201 - Click to enlarge]

selecteven().QTGMC(inputtype=2, sharpness=0.5)

[Attachment 54202 - Click to enlarge]


No ghosting for either ; the main difference is less aliasing with QTGMC processing (you can compare the hat, glass rims, super mario etc...)


Typical culprits that could explain your results are bad source filter (that version lsmash is ok, it's the same one I'm using.), old prerequisites plugins, maybe wrong downloaded video maybe some issues with it

[AndersonJames]

I'm using the Trimmed source clip I uploaded in my first post. I'm talking about frame number 146 and 147. The ghosting issues shown in the photo I uploaded only show when I add the QTGMC lines in the script.

The following script displays fine for me without ghosting:

LWLibavVideoSource("L:\Trimmed VP9.mkv") 

SelectEven()

When I use the full script including QTGMC I get the ghosting:

LWLibavVideoSource("L:\Trimmed VP9.mkv") 

SelectEven()
a=last

a
QTGMC(inputtype=2, sharpness=0.5)
b=last

b.Trim(0,1272) ++ a.Trim(1273,0)

If you don't get ghosting on your PC can you please give me a zip of your Avisynth plugins directory and tell me which Avisynth version you have installed. I'll try using the same to see if it fixes the issue. Never seen a problem like this before after years of using QTGMC!

[manono]

I think he uploaded in 23.976p.

You're dead wrong. As pdr said, YouTube doesn't increase the original framerate.

Do you have a link to a YouTube video which uses 23.976fps?

My own channels are all film-based and all the 1400 or so videos are 23.976fps. Most of what you claim throughout this thread is sheer nonsense.

[poisondeathray]

There are problems with the version you downloaded (and uploaded to post #1), or perhaps it was the way you cut it, or the way it's being decoded. That's at least one of the problems

eg. In your version, just the source filter, already frame 0, frame 1 are duplicates with selecteven(). But the original VP9 version is clean, no duplicates with the same source filter with selecteven()

It's clean for me if you download the AVC version or VP9 version from youtube with that script

[poisondeathray]

vp9/opus version downloaded with this

youtube-dl -f 303+251 https://www.youtube.com/watch?v=6CA9ilybJ5Q

I stream copy / cut the intro with ffmpeg uploaded here as "cut.webm" 43 seconds for the intro + a bit of the other section uploaded below

ffmpeg -i "Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.webm" -c:v copy -c:a copy -t 00:00:43 cut.webm

encode the script , stream copy the opus audio (no reason to re-encode or degrade the audio). The output is q.mkv uploaded below

ffmpeg -i 1_vp9_cut.avs -i "cut.webm" -map 0:0 -map 1:1 -c:v libx264 -crf 18 -c:a copy q.mkv

You can actually probably cut the video into 2 sections, and just re-encode/process the 1st part then join, since the 2nd is unfiltered. That way you don't have to re-encode the 2nd part. But cutting and joining vp9 is not straight forward


I think there is an issue with your downloading method, or cutting method

[AndersonJames]

There are problems with the version you downloaded (and uploaded to post #1), or perhaps it was the way you cut it, or the way it's being decoded. That's at least one of the problems

eg. In your version, just the source filter, already frame 0, frame 1 are duplicates with selecteven(). But the original VP9 version is clean, no duplicates with the same source filter with selecteven()

It's clean for me if you download the AVC version or VP9 version from youtube with that script

I've updated my 1st post to provide you the full untouched source video that I downloaded via the YouTube-DL program. Here's the batch script I used to download the video:

cd /D "%~dp0" 
youtube-dl -f ("bestvideo[width>=1920]"/bestvideo)+bestaudio/best https://www.youtube.com/watch?v=6CA9ilybJ5Q -o "L:/YouTube/%%(upload_date)s    %%(title)s    %%(id)s    New Zealand %%(height)sp @@%%(vcodec)s %%(acodec)s@@. FPS %%(fps)s, Views %%(view_count)s.%%(ext)s" --embed-subs --sub-lang en --ignore-errors --restrict-filenames --download-archive archive.txt --merge-output-format mkv
youtube-dl https://www.youtube.com/watch?v=6CA9ilybJ5Q -o "L:/YouTube/%%(upload_date)s    %%(title)s.%%(ext)s" --ignore-errors --restrict-filenames --write-description --write-thumbnail --skip-download 
PAUSE

Even on that video, frames 0 and 1 are still duplicates for me after using SelectEven(). Why are you getting a different video without those issues? Can you give the above download script a try please and tell me if frames 0 and 1 are duplicates for you? I don't understand why I'm getting these ghosting issues and why QTGMC is not having any effect on the jaggies.

[poisondeathray]

Yes there is a duplicate in your video when decoded with lsmash and SelectEven(). It might be something with buggy mkv timestamps. You can remux it with ffmpeg it seems to work in terms of no duplicates, QTGMC working properly, at least for me

ffmpeg -i "VP9 Untouched Source from YouTube-DL.mkv" -c:v copy -c:a copy remux.mkv

Maybe the --merge-output-format did something to it. I just used the plain youtube-dl command posted earlier an it worked as-is

[poisondeathray]

EDIT: And downloading with your batch (just changing the directory) , it works ok in terms of no duplicate

I'm checking with lsmash and selecteven()

But your video in post #1 has the duplicate after selecteven()

[poisondeathray]

The bytes are different
97,420,702 bytes for youtube-dl batch download just now
97,420,716 bytes for your version from post #1

I was using youtube-dl dated 2020-05-28, not sure if that makes a difference.

The timestamps look ok; it's something else that is the problem

[AndersonJames]

In the script I used in post 1 to download, I removed the MKV merge bit and I get a .webm file. In AVSPmod when previewing the video, frames 0 and 1 are still duplicates. This is before I've encoded the video.

Don't understand why you used the same script as me which I provided to download the file yet I'm getting duplicate frames on frame 0 and 1? Are you sure you used the same script as me to download apart from the directory?

[poisondeathray]

Don't understand why you used the same script as me which I provided to download the file yet I'm getting duplicate frames on frame 0 and 1? Are you sure you used the same script as me to download apart from the directory?

To be clear, I'm talking about duplicate still there after SelectEven(). It shouldn't be there

I'm certain, just the directory difference. And possibly youtube-dl version difference.

Did you try cut.webm above ? Did you get the duplicate frame after selecteven() (Not taking about QTGMC yet)


There are some byte differences between what I get with your script and what you uploaded. Try downloading it again. Maybe something got corrupted the 1st time

[AndersonJames]

vp9/opus version downloaded with this

youtube-dl -f 303+251 https://www.youtube.com/watch?v=6CA9ilybJ5Q

I stream copy / cut the intro with ffmpeg uploaded here as "cut.webm" 43 seconds for the intro + a bit of the other section uploaded below

ffmpeg -i "Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.webm" -c:v copy -c:a copy -t 00:00:43 cut.webm

encode the script , stream copy the opus audio (no reason to re-encode or degrade the audio). The output is q.mkv uploaded below

ffmpeg -i 1_vp9_cut.avs -i "cut.webm" -map 0:0 -map 1:1 -c:v libx264 -crf 18 -c:a copy q.mkv

You can actually probably cut the video into 2 sections, and just re-encode/process the 1st part then join, since the 2nd is unfiltered. That way you don't have to re-encode the 2nd part. But cutting and joining vp9 is not straight forward


I think there is an issue with your downloading method, or cutting method

I tried the first 2 scripts in your post and I get the "cut.webm" file. Opening that in AVSPmod I still get duplicate frames. The 3rd script which I put after the other 2 scripts fails saying "1_vp9_cut.avs: Unknown error occurred". Full output of the batch file is below:

X:\Portable Installations\YouTube-DL>cd /D "X:\Portable Installations\YouTube-DL
\"

X:\Portable Installations\YouTube-DL>youtube-dl -f 303+251 https://www.youtube.c
om/watch?v=6CA9ilybJ5Q
[youtube] 6CA9ilybJ5Q: Downloading webpage
[download] Destination: Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thous
ands Stolen! Be Careful!-6CA9ilybJ5Q.f303.webm
[download] 100% of 86.03MiB in 01:01
[download] Destination: Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thous
ands Stolen! Be Careful!-6CA9ilybJ5Q.f251.webm
[download] 100% of 6.88MiB in 00:07
[ffmpeg] Merging formats into "Massive Twitter Hack! Obama, Mr. Beast & Even GOD
! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.webm"
Deleting original file Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousa
nds Stolen! Be Careful!-6CA9ilybJ5Q.f303.webm (pass -k to keep)
Deleting original file Massive Twitter Hack! Obama, Mr. Beast & Even GOD! Thousa
nds Stolen! Be Careful!-6CA9ilybJ5Q.f251.webm (pass -k to keep)

X:\Portable Installations\YouTube-DL>ffmpeg -i "Massive Twitter Hack! Obama, Mr.
 Beast & Even GOD! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.webm" -c:v copy -c:
a copy -t 00:00:43 cut.webm
ffmpeg version N-65018-gad91bf8 Copyright (c) 2000-2014 the FFmpeg developers
  built on Jul 26 2014 22:09:15 with gcc 4.8.3 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-lib
modplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrw
b --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinge
r --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --en
able-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis
 --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-
libx265 --enable-libxavs --enable-libxvid --enable-decklink --enable-zlib
  libavutil      52. 92.101 / 52. 92.101
  libavcodec     55. 69.100 / 55. 69.100
  libavformat    55. 49.100 / 55. 49.100
  libavdevice    55. 13.102 / 55. 13.102
  libavfilter     4. 11.102 /  4. 11.102
  libswscale      2.  6.100 /  2.  6.100
  libswresample   0. 19.100 /  0. 19.100
  libpostproc    52.  3.100 / 52.  3.100
Input #0, matroska,webm, from 'Massive Twitter Hack! Obama, Mr. Beast & Even GOD
! Thousands Stolen! Be Careful!-6CA9ilybJ5Q.webm':
  Metadata:
    encoder         : Lavf55.49.100
  Duration: 00:08:22.94, start: 0.007000, bitrate: 1549 kb/s
    Stream #0:0(eng): Video: vp9, yuv420p, 1920x1080, SAR 1:1 DAR 16:9, 60 fps,
60 tbr, 1k tbn, 1k tbc (default)
    Stream #0:1(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
Output #0, webm, to 'cut.webm':
  Metadata:
    encoder         : Lavf55.49.100
    Stream #0:0(eng): Video: vp9, yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31,
 60 fps, 1k tbn, 1k tbc (default)
    Stream #0:1(eng): Audio: opus, 48000 Hz, stereo (default)
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 2777 fps=0.0 q=-1.0 Lsize=   23037kB time=00:00:42.99 bitrate=4389.7kbits
/s
video:22413kB audio:589kB subtitle:0kB other streams:0kB global headers:0kB muxi
ng overhead: 0.151192%

X:\Portable Installations\YouTube-DL>ffmpeg -i 1_vp9_cut.avs -i "cut.webm" -map
0:0 -map 1:1 -c:v libx264 -crf 18 -c:a copy q.mkv
ffmpeg version N-65018-gad91bf8 Copyright (c) 2000-2014 the FFmpeg developers
  built on Jul 26 2014 22:09:15 with gcc 4.8.3 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-lib
modplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrw
b --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinge
r --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --en
able-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis
 --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-
libx265 --enable-libxavs --enable-libxvid --enable-decklink --enable-zlib
  libavutil      52. 92.101 / 52. 92.101
  libavcodec     55. 69.100 / 55. 69.100
  libavformat    55. 49.100 / 55. 49.100
  libavdevice    55. 13.102 / 55. 13.102
  libavfilter     4. 11.102 /  4. 11.102
  libswscale      2.  6.100 /  2.  6.100
  libswresample   0. 19.100 /  0. 19.100
  libpostproc    52.  3.100 / 52.  3.100
1_vp9_cut.avs: Unknown error occurred

X:\Portable Installations\YouTube-DL>PAUSE
Press any key to continue . . .

I tested your cut.webm file in AvsPmod and there's NO duplicate frames. I don't understand why you don't get duplicate frames and I do when we're both using the same download script? I have Youtube-DL version 2020.6.16.1
Does your script still work when using that version and are the frames missing in the cut.webm file created when using that version?