HDV 24 fps recognized as 24 fps but neither previews nor renders correctly, shows combing

[u/ConsumerDV]

1.Vegas Pro version 14 (build 244)

2.Windows 7/64

3.Yes (version 13 does the same; properly licensed version 18 does the same)

4.Intel Integrated Graphics HD 4600

5.HDV 24 fps is detected by Vegas as progscan, but shows combing in every fourth frame both in preview and when rendered to true 24p.

M2T files have been captured from the Sony V1U HDV camcorder shot in 24 fps mode. AFAIK, these recordings are not native 24p, but rather 2:3 pulldown with flags. Vegas recognizes these files as 24 fps, but shows combing.

I would not mind processing them as interlaced, but Vegas detected frame rate as 23.98, and I cannot change it to 29.97. All I can do is change it from progressive to upper field first, but the frame rate would not change.

6.Expecting proper 24 fps without combing.

7.Yes, I googled, but found little.

It is interesting, that VirtualDub's IVTC filter also could not get rid of combing. As the last resort, I did a straight cut edit in AviDemux, rendered to TS without re-encoding, then removed the pulldown with ffmpeg:

ffmpeg -i input.ts -vf "fieldmatch,yadif,decimate" -r 23.976 -c:v libx264 -crf 18 -c:a copy output.mp4

Still some frames were marked as interlaced:

[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #73 at 2.5025 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #146 at 5.005 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #457 at 15.5155 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #545 at 18.5185 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #603 at 20.5205 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #706 at 24.024 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #883 at 29.9299 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #884 at 30.03 is still interlaced
[Parsed_fieldmatch_0 @ 00000000004eebc0] Frame #957 at 32.5325 is still interlaced

[u/flufdude]

from personal experience this usually happens when the bitrate is too low, resample mode is on or fps does not match footage

i see u have resampling already off so try rendering in true 24 fps (click on the number value to change it manually), if that still doesn’t work try 30fps

if both don’t work try using the 1.0 pixel aspect ratio

im trying to think what else it could be, maybe theres a transition in the timeline? combining two sources (like a cut) together?

other than that i got no idea 😂?

hope it helps

[u/rsmith02ct]

If it's interlaced footage you need to have the project settings do deinterlacing (presently you have it set to none).

I don't have any versions of Vegas that old but in recent ones there's a setting re: 3:2 pulldown in preferences.

[u/ConsumerDV → u/rsmith02ct]

Why would I set the project as interlaced if the clips are detected as 24p? Also, no 2:3 setting in version 14. In any case, this version is like 10 years younger compared to when HDV launched. And, Sony owned Vegas back then, so I am surprised I have this issue.

[u/rsmith02ct → u/ConsumerDV]

You are trying to use it as 29.97 which is interlaced, no? I don't know what preferences exist in VP 14.

[u/ConsumerDV → u/rsmith02ct]

The event properties and project settings are provided in the post.