I'm trying to deinterlace MP4 1080i HD video files, but when using QTGMC in AvsPmod it keeps repeating itself in a sort of looping back and forth motion, although the audio plays at normal speed. I'm also having the issue of the video playing too fast once it goes from 50i to 50p.
Avisynth really does not like non-AVI sources.
Convert the 1080p files to lossless Lagarith. Yes, the file will be ugly huge in size, but that's life in HD.
Alternatively, you could try to use FFmpegSource instead of lsmash to load the file. Though, be aware that ffmpegsource has to index the file, which can take a little while the first time it's loading the file.
Avisynth really does not like non-AVI sources.
Convert the 1080p files to lossless Lagarith. Yes, the file will be ugly huge in size, but that's life in HD.
The strange thing is it runs fine when using other deinterlacers such as bob and Yadif, so must be a problem mainly with QTMGC
Ok i've converted it to an AVI using Lagarith, but now getting this error in AvsPmod..
Code:
AVISource: couldn't locate a decompressor for fourcc LAGS
Quote:
Originally Posted by sanlyn
Throwing away half of your video and then deinterlacing afterwards?
You're kidding, right?
Oh didn't realise you had to have things in a certain order I'm still new to all this.. Was just trying out different settings to see if it would sort out the speeded up video problem
So if i was going from 50i to 25p i would still lose half the picture information?
Last edited by Master Tape; 06-29-2018 at 04:52 AM.
Statements are executed in the order in which they appear.
Discarding alternate frames destroys 50% of your temporal resolution. Is that what you want? Why discard even-numbered frames, why note discard odd-numbered frames instead with SelectOdd()? Maybe the even numbered frames look cleaner than the odd frames (that's often the case with many sources, depending on how the mp4 was made). Why are you using QTGMC with the "slower" preset? Do you know what "slower" does? Are you sure you want that much processing on a lossy original? Why are you deinterlacing in the first place?
Statements are executed in the order in which they appear.
Discarding alternate frames destroys 50% of your temporal resolution. Is that what you want? Why discard even-numbered frames, why note discard odd-numbered frames instead with SelectOdd()? Maybe the even numbered frames look cleaner than the odd frames (that's often the case with many sources, depending on how the mp4 was made). Why are you using QTGMC with the "slower" preset? Do you know what "slower" does? Are you sure you want that much processing on a lossy original? Why are you deinterlacing in the first place?
I don't even know why i put SelectEven() in there, i wasn't entirely sure what it did, i was switching between that and AssumeFPS(25) but now i wont use it after learning it throws half the image away!
I guess 'Slower' is a little overkill but i just want to maintain as much quality as possible.
I want to deinterlace so i can upload clips to my Youtube.
Select Odd/Even doesn't "throw away" data as much as restore the original framerate. If the intended new format can use 50/59.94fps, then great, go for it. But if not, you must decimate it back to the original 25/29.97, no choice in the matter. While it is true that interlace fields are each a discrete moment in time, it's also at 50% size. The deinterlace process creates full-sized frames via interpolation of data. In effect, you have 50/60 new frames that previously did not exist. And sometimes even the field data is interpolated, not untouched, so not always 50/60 discrete moments after all.
Another offset of double frames = 200% file size (lossless), at least 125% compressed formats.
Youtube can handle 50/59.95fps. So just do that.
I've found myself using "faster" quite a bit this year, as quality between slow and fast/faster is sometimes negligible.
Eureka! We're finally getting somewhere now. Installed the Lagarith codec and the avi is opening up fine. After rendering the file there's still a little problem.. Whilst everything all plays fine, the file is flagging up as 42 seconds when it should only be 21 seconds. Not sure what's happened there, but at the end of the 21 seconds when the video should end, it then kind of loops the last 2 frames simultaneously for another 21 seconds. I mean i can always trim it out, but would rather the problem not be there as it doubles my rendering time.
Also there's some horrid pixelation going onscreen in my test video during the ident, though it's present in the original source (probably because there's too much going onscreen at once, all the falling petals, ect) Is there a good script to reduce the appearance of this?
Last edited by Master Tape; 06-30-2018 at 02:50 AM.
I'm still new to all this.. Was just trying out different settings to see if it would sort out the speeded up video problem
