Skip to main content
Participant
July 2, 2024
Question

How to deinterlace 480i to 480p: are these the correct steps?

  • July 2, 2024
  • 2 replies
  • 1689 views

Source footage is 720x480 interlaced, 29.97fps. I would like to make it 720x480 progressive, 59.97fps.

 

Are these the correct steps:

  1. Drop video file into Assembly media area
  2. Right click on video file and select Modify - Interpret Footage
  3.  In Field Order area, change to Conform to No Fields (Progressive)
  4. Press OK
  5.  Create sequence with settings 720x480, progressive, 59.97fps
  6. Drop video into timeline (click Keep existing settings)
  7. In timeline, right click video and select Field Options
  8.  Select Always Deinterlace
  9.  Click Export tab
  10.  Under Video - Basic video settings, click Match Source
  11. Click Export

 

When I follow these steps, my video has those interlaced lines around the edges of objects. So what I am doing wrong?

This topic has been closed for replies.

2 replies

Averdahl
Community Expert
Community Expert
July 3, 2024

@TS1993 In this case you could just drop the interlaced 29.97 fps footage on a progressive 59.97 fps timeline. No need to do anything with the interlaced 29.97fps footage, Premiere Pro takes care of everything.

Remote Index
July 3, 2024

Averdahl,

 

Thanks for contribuiting this tip. Interesting. Half the visual resolution at double the temporal resolution. The frame rate will definitely have a different "look" from 29.97 but this might be the starting point for a workflow that includes optical flow. I'd be interested if you know of those who have worked with these issues more.

 

R.

R Neil Haugen
Legend
July 3, 2024

Interlaced is interlaced ... as was heavily covered in a long discussion on this on the Facebook Premiere pro editor's group, by quite a number of folks with long broadcast experience. Like Joost has, btw ... he's quite a noted broadcast editor/colorist if you are not aware.

 

"29.97i" is actually always technically 59.94 ... it's always just half the data, the odd-lines/even-lines thing. Normally set for one field, upper or lower, 'first'. So you have 59.94 discrete frames per second, alternating which (odd/even) line has actual image data. "29.97i" is simply another way to name that pattern.

 

Does that help thinking about this? It did for me. 

Everyone's mileage always varies ...
Joost van der Hoeven
Community Expert
Community Expert
July 2, 2024

Premiere does this automatically if you set it up correctly:

  1. Make sure your footage has the proper interpretation: so interlaced, 29.97fps. Check via Modify - Interpret Footage in the project panel.
  2. Right click on the clip in the project an choose New Sequence form Clip
  3. With the newly create sequence selected, got to the Menu Bar and choose Sequence > Sequence Settings...  and change the Editing Mode to Custom and set the Timebase to 59.94fps (59.97fps does not exist). An click OK

 

You are now good to go, Pr knows the clip is interlaced and lives in a progressive timeline and shouldn't see combing. If you want, you can use Optical Flow on your clip to have Pr generate the missing frames from the original fields. Right Click on the clip in the timeline and Choose Speed/Duration... and only change the Time interpolation to Optical Flow

 

Note: SD video is/was alwas non-square pixels; depending of how your 720x480, 29.97fps shot was filmed, it's the pixel aspect ration is either 0.9091 (4:3) or 1.2121 (widescreen). So you might want to convert these to square pixels too while you are doing this. See this page.

TS1993Author
Participant
July 2, 2024

Thanks! Just want to double check something. Is the Interpret Footage settings meant to be set to what the raw video is, or what the final video is meant to be? From your answer above, I assume the former. Is that correct?

Joost van der Hoeven
Community Expert
Community Expert
July 2, 2024

No, the interpret footage on the clip should be just vanilla, they should state what the clip is. I your case 29.97fps, interlaced, probably lower field first,