Interlacing question

Plex Players Desktop Players
1

Hi All,

i have a video which I would like to view via Pley, the original file does not have any visible interlacing (right side), but when I play the file via the web player (left) i have heavy interlacing and really bad quality even though there is no transcoding.

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How does this happen and is there anyhting I can do about it?

Thanks!

2

VLC does automatic deinterlacing.
A web browser is not able to do that.
Either you

  • force Plex to transcode
  • convert the video with e.g. Handbrake to remove the interlacing
  • use Plex for Windows/Mac or Plex Media Player to play the file

Interlacing is a relic of CRT TVs. No flat screen needs it and all it does is making the picture quality worse, due to the need to remove the interlacing prior to displaying the picture.
So if you can, disable interlacing in your camera.

2 Likes
3

A question Otto, if recording from Terrestrial Television with DVR, will Plex Transcode if the source is Interlaced?

4

It should, if the client doesnā€™t support interlaced video. Whether it actually does, needs to be determined.
Weā€™d need server ā€˜debugā€™ logs for that.

1 Like
5

So the answer is that the Client is the determining factor, considering all TVā€™s are supporting Interlacing Broadcasts with there tuners

6

I just tested, and I get a de-interlaced and transcoded video when I play an old SD interlaced video in the web client.

I know deinterlacing doesnā€™t yet work in the Plex for Windows/Mac app.
It does work in Plex Media Player (if you enable it in the settings in TV mode).

7

A TV usually supports interlaced video, yes.
But this thread is about the web app. The video is decoded by the web browser. And it will only deliver a progressive video signal to the screen driver, because it doesnā€™t have exclusive access to the screen but has only a ā€œwindowā€.

8

Thank you.

Actually i aksed my self why there even is interlacing in the first place. The material is from my iPhone (and i donā€™t think there sould be any interlacing). I jsut checked content that was directly created in Adobe Premiere

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and disabled deinterlacing in vlc -> heavy interlacing. Iā€™m not en expert on video codecs, but i guess theres sth. wrong with the export profileā€¦

9

Verify that the Summary > Output in Premiere says ā€˜Progressiveā€™.
and the ā€˜Field Orderā€™ on the ā€˜Videoā€™ tab is set to ā€˜Progressiveā€™. If it says ā€˜Upper/Lower Firstā€™, youā€™ll get interlacing.

10

@OttoKerner: Yes thank you - that did the job.

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