Issues in converting 480i video to 1080i

[poisondeathray]

I don't care about Toon!verse logo. that is original 1080i logo, so It must have aliasing and halos.
and halo in frame edges and character also ok for me, because it is almost looking similar to original in my eye.

The logo and border are not important, but the artifact distribution are clues - because the halos around other objects , and if you check other scenes, are predominantly the same distribution. It suggests to me the settings are still slightly off

If you're happy that's all that matters . Personally I prefer fewer artifacts

[sdx12349]

ah, I thought I was satisfied, but ringing effect looking much worse in 2:1 pixel match than 1:1 pixel match.
I guess height value is almost perfect, so I added some resizing option.. the s=0 parameter.
It reduced some halos, but it's not perfect..
is this the limit that I could be done?

here's my result.

[poisondeathray]

ah, I thought I was satisfied, but ringing effect looking much worse in 2:1 pixel match than 1:1 pixel match.
I guess height value is almost perfect, so I added some resizing option.. the s=0 parameter.
It reduced some halos, but it's not perfect..
is this the limit that I could be done?

here's my result.

Besides fiddling with height and s, you can also try playing with the b,c settings

Otherwise you can try other adding other filters, AA, dehalo filters. There are dozens to choose from

Machine learning filters can definitely improve this, and there are many geared towards anime - However almost all will be trained on progressive images, not a field. If you separatefields, apply, then weave, there is a significant chance of distortions. You would need to IVTC, which you've made clear you don't want to do

[sdx12349]

UPDATE: I FOUND THE PERFECT SOLUTION!!!
Descale Filter's DeBilinear function perfectly recovers 480i/486i SD Video that wrongly converted to 1080i..
Here's my code.

LoadPlugin("LSMASHSource.dll")
LoadPlugin("libdescale.dll")
interlaced_clip =  LWLibavVideoSource("in.mkv").ConvertToYUV444(interlaced=true, matrix="Rec709")
top = interlaced_clip.SeparateFields().SelectEven()
bottom = interlaced_clip.SeparateFields().SelectOdd()

target_height = 243

top_descaled = top.DeBilinearResizeMT(720, target_height, src_height=target_height, src_top=0.5)
bottom_descaled = bottom.DeBilinearResizeMT(720, target_height, src_height=target_height)
final_video = Interleave(top_descaled, bottom_descaled).Weave().AssumeTFF()
return final_video.ConvertToYV12()

[Selur]

*gig* So, basically what poisondeathray suggested at the beginning you just changed 243 over 240,...
(since DeBilinearResizeMT has no temporal component, SeparateFields + Resize + Weave should be the same as what you do)


Cu Selur

[jagabo]

Good find sdx12349. 243 line fields makes sense since 486 line frames is fairly common for SD NTSC caps.

[sdx12349]

*gig* So, basically what poisondeathray suggested at the beginning you just changed 243 over 240,...
(since DeBilinearResizeMT has no temporal component, SeparateFields + Resize + Weave should be the same as what you do)


Cu Selur

Yeah, if I just change 240 to 243, split top/bottom field and add src_top=0.5 in one of the top/bottom field in poisondeathray's first suggested script, then It is same...
But, Other resize filters aren't good. Only Descale Filters like DeBilinear was the most same as original video in my case.
other resize filters add ringing or aliasing effects.

and, final script that I wrote is still has problem like the Image below...
I think it's chroma problem, but I don't have an idea about how to fix it.
Can somebody solve this problem?

[Selur]

which of the provided samples has this issue?

[sdx12349]

which of the provided samples has this issue?

Attachment of this thread, starts "2 - 투니버스"
and this thread attachment, "학교괴담OP.ts" and "학교괴담ED.ts".

[jagabo]

ConvertToYV12() on the last line of your script should be ConvertToYV12(interlaced=true).

[Selur]

Sorry, can't help.
I looked at * "학교괴담OP.ts", "학교괴담ED.ts", "2 - 투니버스_20250809_235850.ts", "2 - 투니버스_20250809_235546.ts" and couldn't spot any such chroma issue.
¯\_(ツ)_/¯

ConvertToYV12() on the last line of your script should be ConvertToYV12(interlaced=true).

well spotted

[sdx12349]

ConvertToYV12() on the last line of your script should be ConvertToYV12(interlaced=true).

hmm... no. It's same. maybe my ffmpeg setting was wrong?

ah, sorry! it worked! just I forgot to save the script.