Help with cropping & adding black borders with Avisynth

[jda]

I have some 720x480 (4:3) captured video that I want to remove 2 pixels off of the left and 20 off of the right then add black borders to compensate. I used to know how to do this with Avisynth, but haven't played with this stuff in years and can't remember how to do it right. I did some searches and tried some of the suggestions in various archived posts but haven't had any success. If anyone can help I would appriciate it. Thanks.

[Jim44]

Crop and AddBorders are probably the filters you are looking for (names are clickable links to the AviSynth Wiki pages).

Hopefully that'll jog your memory.

[txporter]

Crop(2,20,0,0) - crop wiki page
AddBorders(2,20,0,0) - Addborders wiki page

avisynth script could look something like:

mpeg2source("video.d2v") # - need to index file with DGindex
crop(2,20,0,0)
addborders(2,20,0,0)

[poisondeathray]

What format did you capture in?

Be careful, if it's interlaced YV12, crop needs to be multiple of 4. If it's interlaced YUY2, then crop multiple of 2 is ok

[manono]

He said 2 from the left and 20 from the right, so even if interlaced YV12, Mod 2 should be OK, shouldn't it? So:

Crop(2,0,-20,0)
AddBorders(10,0,12,0)#to distribute the black more evenly.

[poisondeathray]

^ yes you are correct manono . According to that wiki , cropping width by 2 is ok for interlaced yv12, and only height has the mod4 restriction . My bad.

[jda]

Problem solved.

This worked out really well.

Crop(2,0,-20,0)
AddBorders(10,0,12,0)#to distribute the black more evenly.

Thanks everyone for the help.

[jagabo]

I would add keep the left border mod 8 in size for better compression and less artifacts.

Crop(2,0,-20,0)
AddBorders(8,0,14,0)#to distribute the black more evenly

At least one edge falls on a mod 8 boundary this way.

[txporter]

He said 2 from the left and 20 from the right, so even if interlaced YV12, Mod 2 should be OK, shouldn't it? So:

Crop(2,0,-20,0)
AddBorders(10,0,12,0)#to distribute the black more evenly.

Oops. Guess I should have read the page better myself.

[2Bdecided]

Seems a waste of time padding it to 720 - just encode 704x480 e.g.

Crop(2,0,-20,0)
addborders(2,0,4,0)

or even just
crop(0,0,-16,0)

(same result, just keeps the original black and probably original soft edges which will encode slightly more easily without ringing artefacts)

Cheers,
David.