|
05-26-2020, 10:18 AM
|
|
Invalid Email / Banned / Spammer
|
|
Join Date: Apr 2020
Location: Sandgroper country, Australia
Posts: 777
Thanked 141 Times in 131 Posts
|
|
|
Hello all again,
I'm now working on a video for personal use only, a portion of which is a clip from Youtube (attached).
I cannot get the section to play in VLC or my Android devices without huge jaggies. I initially thought it was interlacing but whatever I try to deinterlace it (Handbrake, AVIdemux AVI to VDub) I cannot improve it. I strongly suspect that it is not interlaced (Mediainfo says not), but it looks like it to my untrained eye.
I would be grateful if the experts could tell me what's wrong with the clip and is there any way of fixing it.
The problem is best observed at the end, just as the aeroplane takes off and passes the camera (3m 45s 22f).
Thanks a lot, Al
|
|
Someday, 12:01 PM
|
|
Ads / Sponsors
|
|
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
|
|
|
|
|
05-26-2020, 11:02 AM
|
|
Free Member
|
|
Join Date: Dec 2017
Location: Norway
Posts: 1,685
Thanked 465 Times in 395 Posts
|
|
It looks a bit like an interlaced video clip that has been scaled (and encoded) as progressive. If interlaced (weaved) video is scaled as though it was progressive there will no longer be alternating lines of each field, but something else depending on whatever the scaling algorithm does. Additionally, encoding an interlaced clip with 4:2:0 h.264 (the codec/format usually used for viewing and on yt these days) will mess with the weave pattern too, and it will mess up the chroma even more.
If you can't get the original somehow (from the uploader or elsewhere) you may be able to improve it a bit with some advanced avisynth trickery to divide the frames into fields manually and then deinterlace, but the video has already been messed up to a degree.
Even big producers seem to sometimes end up messing up youtube uploads in this way..... https://www.youtube.com/watch?v=v2AC41dglnM
|
|
05-27-2020, 01:58 AM
|
|
Site Staff | Video
|
|
Join Date: Dec 2002
Posts: 15,476
Thanked 2,835 Times in 2,404 Posts
|
|
|
When you scale interlace, bad things happen. The clip was screwed up pre-Youtube.
I see this way too much from "professional" outlets (somebody non-professional was hired there), including not just Youtube, but broadcast TV. I've seen archived news clips on CNN, for example, that have so much damage that you really cannot see what's going on in the clip anymore. Maybe CNN did it, or maybe the source of the clip (news station) did it. But somebody up the chain screwed the clip up.
VirtuaDub has an area-based deinterlacer, but the outcome will only be less-bad, not good.
|
|
05-27-2020, 04:22 AM
|
|
Invalid Email / Banned / Spammer
|
|
Join Date: Apr 2020
Location: Sandgroper country, Australia
Posts: 777
Thanked 141 Times in 131 Posts
|
|
Quote:
|
VirtuaDub has an area-based deinterlacer
|
Thanks LS, which one is it? I might give it a crack. I'm using 32 bit VD.
|
All times are GMT -5. The time now is 03:24 PM
|