Deinterlace doesn't produce high motion video

Hello again,

I’m having an issue with exporting a project I’m working on. It includes an 1080i video source that has 60 fps when doubled. When exporting, I made sure to pick either YADIF or BWDIF as the deinterlacer. However after encoding, the video still looks like it’s stuck at 30fps, despite what MediaInfo says.

Am I doing something wrong, or is this expected?

Thank you.

You need to use Properties > Convert > Advanced on the video to double the frame rate with deinterlace. Shotcut does not do that in realtime.

Thank you for the answer.

I think I might’ve not portrayed my issue properly. This is not about playing the video real-time at 60fps, this is about what’s exported. The video is deinterlaced, but it’s not doubled, only the elements added in to shotcut play at 60fps high motion, the rest is playing at standard (?) motion.

Hope this makes more sense.

Thank you.

If you have 30fps interlaced and you want to convert to 60fps progressive make sure you:

  • Set your video mode to a format that is 60fps
  • Run Properties > Convert Advanced and click “deinterlace” to make an intermediate file with 60fps with each field converted to a frame
  • Open the intermediate file in Shotcut with the 60fps video mode

So I take it that it’s not possible to have the video deinterlaced/convert each field to a frame at the export step? It’s only possible if that was already done to the video?

Correct. We have a batch conversion feature so you can select all your interlaced clips and perform a batch conversion to perform interlace conversion from 60 fields per second to 60 frames per second. Yes, the files will be bigger than you original files.

Is this a technical limitation, or this is intended as such?

It is how it is currently designed and nobody has volunteered to make it different. Making it work the way you want would require some changes to the underlying MLT framework.

It is getting harder to get people interested in features for interlaced video since progressive is the way of the future. Volunteer developers are more interested in adding features for modern capabilities.

Alright, thank you both for your answers!