Your source had been captured at 50fps. Should have been 25fps.
AssumeFPS is not the correct way, rather SelectEvery(2,0).
(Since content is the same for 2 consequent frames you throw away every other frame.)
Now you get the interlaced 25fps of the source back without having to recapture.
P.S. No, flagging of the capture was wrong.
Tells 50fps but is indeed 25fps. Your choice was correct: Assumefps(25)
From there go to QTGMC. Here you get the 25fps field-frames bobbed to 50fps progressive.
Then you may crop off any garbage, head noise, 2x 8..10 pix black pillars as you did.
Then you may resize vertically to suit your playback device to 576? 720 ?
If DVD then PAL 576, then obey the SAR/DAR for 4:3 then no 50p possible, reinterlace to 25i.
If Blu-ray then 720 @ simply SAR=DAR=1:1, then 50p possible too.
then resize horizontally until you get round circles/balls while previewing with the correct SAR/DAR.
Use VirtualDub, your eyes and a ruler for that.
Cropping after resizing left you with a 736x564 pixel video, only a mediaplayer can play that.
You may check that using medainfo.
And, even if DAR was embedded as 4:3, PAR is destroyed by doing crop after resize.
You want to crop first, then resize.
A script suggestion for 720p50 Blu-ray:
(you may omit the sharpener, the stabilizer, go for a better dehaloing first)
Code:
v=LWLibavVideoSource("F:\_VID\era uma vez a vida ORIG PIECE.mkv")
a=LWLibavAudioSource("F:\_VID\era uma vez a vida ORIG PIECE.mkv")
AudioDub(v,a)
Assumefps(25)
AssumeTFF()
QTGMC()
Stab()
MedSharp2(str=2)
SmoothCurve(HQ=true, interp=100, limiter=false, debug=false, screenW=1280, screenH=768, \
Ycurve="0-12;30-28;127-127;180-180;240-240;255-245", \
Ucurve="0-0;70-70;123-127;140-140;255-255", \
Vcurve="0-0;70-70;123-127;140-140;255-255")
#Lanczos4Resize(720, 576, src_left=20, src_top=4, src_width=-12, src_height=-7)
Lanczos4Resize(960, 720, src_left=20, src_top=4, src_width=-12, src_height=-7).AddBorders(160,0,160,0)