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15th October 2019, 19:01 | #1 | Link |
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QTGMC in VapourSynth without 2x Frame Rate
Hello,
I want to deinterlace a video with QTGMC but I want to keep original framerate. QTGMC automatically doubles the framerate. In Avisynth, all I had to do was write SelectEven() after QTGMC. How do I do that in VapourSynth? I tried clip = havsfunc.SelectEven() and other combinations but nothing works. Could you help me please? |
15th October 2019, 19:11 | #2 | Link |
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clip = clip[::2]
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VapourSynth - proving that scripting languages and video processing isn't dead yet |
15th October 2019, 21:46 | #5 | Link | |
Cary Knoop
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Quote:
It doesn't! It's you who wants to cut the framerate in half. Last edited by Cary Knoop; 15th October 2019 at 22:10. |
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16th October 2019, 07:06 | #6 | Link |
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I'm using VapourSynth with StaxRip and when I enable the QTGMC filter, the framerate of the result video is shown as having double the frame-rate. I want to keep original framerate. How am I supposed to do nothing? I see it with my own eyes that the end result is double frame-rate!
Also, when using QTGMC in VapourSynth I noticed that CPU Utilization is ~55%. How can I make encoding faster? I was originally using Avisynth but it was also slow with low cpu utilization and though that VapourSynth was faster but as it turns out it isn't. Is QTGMC multi-threaded? My CPU is AMD Ryzen 6-core/12-threads. |
16th October 2019, 09:00 | #7 | Link | |
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16th October 2019, 13:14 | #8 | Link | |
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If 30i is actually 60p, does that mean that videos were really filmed at 60fps and simply interlaced and reduced to 30fps? Last edited by expanseFan; 16th October 2019 at 13:18. |
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16th October 2019, 14:29 | #9 | Link | |
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Quote:
Code:
#### mode - Controls double rate vs same rate output, and whether or not the spatial interlacing check is performed. 0(default) = same rate, do spatial check 1 = double rate, do spatial check 2 = same rate, no spatial check 3 = double rate, no spatial check |
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16th October 2019, 14:55 | #10 | Link |
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I want to convert an interlaced DVD to progressive. Should I convert it to progressive with double the frame rate or keep it at original frame rate?
If for example the dvd has a frame rate of ~29.9fps, should I let QTGMC give me a progressive video with ~59fps? If the DVD wasn't filmed at 59fps then, 59 fps wouldn't be true 59fps. |
16th October 2019, 15:15 | #11 | Link | |
Cary Knoop
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Quote:
The time resolution is 50 and 60, not 25 or 30! If you deinterlace correctly you should reconstruct the missing scan lines instead of trying to get scanlines from one time capture to consolidate with one from a different time capture. And yes many "deinterlacers" do it completely wrong! Last edited by Cary Knoop; 16th October 2019 at 15:40. |
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16th October 2019, 20:25 | #12 | Link | |
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16th October 2019, 15:15 | #14 | Link |
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If you double rate deinterlace it to 59.94, then step through frame by frame , look at the pattern during a scene with motion (such as a camera pan)
1) If there is motion every frame, then it's interlaced content (and you would want to use 59.94p when deinterlacing) 2) If you get duplicates , then it's 29.97p content (then should not deinterlace - you want to field match to 29.97p) 3) If you get 3:2 pattern of repeats, then it's 23.976p content (then you should not deinterlace - it needs to be IVTC'ed) There are exceptions, and weird cadences, changing patterns, but those 3 should cover the majority of common scenarios Last edited by poisondeathray; 16th October 2019 at 15:41. |
16th October 2019, 15:56 | #17 | Link |
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before the time that modern digital cameras like Arri Alexa were introduced, the image quality of any non-film based material is basically garbage. back then you gotta use film cameras like Arriflex 435 to shoot high quality videos. since footages shot on film are apparently progressive, that leaves all native interlaced content nothing but abysmal quality, which is not worth saving anyways.
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16th October 2019, 16:40 | #18 | Link | |
Cary Knoop
Join Date: Feb 2017
Location: Newark CA, USA
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Quote:
So no, I disagree that some things are not worthy to be saved because of a bad quality. |
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