Keeping interlaced material interlaced?

[AVR2]

I have a lot of natively interlaced MPEG-2 video that I want to convert to MP4 whilst retaining the interlace, so that the video keeps its original "live video look" rather than deinterlace it to give it a "filmic" look.

I'm seeing lots of support articles for Handbrake about how to deinterlace material, but nothing on ensuring that the original interlace is maintained. If I run an encode with Decomb/ Deinterlace switched OFF, does that mean Handbrake will maintain the interlace?

I've done a test encode like that, and when I played it back in both VLC and Plex, I saw combing artefacts that appeared to be burned in - I couldn't make the video display in its original video look. By contrast, if I export as an MP4 from MPEG Streamclip and play back in Plex with "Interlaced Handling" set to "Bob", the original video look is there.

[TedJ]

Add either tff or bff to the additonal options box on the video tab.

http://mewiki.project357.com/wiki/X264_Settings#tff

[Deleted User 13735]

In order to play correctly on anything but an old CRT, a deinterlace filter will need to be invoked after decoding, so why go through this?

[BradleyS]

HandBrake has a pretty decent bob filter, if you're looking to preserve the original motion. IMHO it is better to bob then playback progressive than to encode interlaced.

[AVR2]

Thanks guys. I discovered the "bob" filter almost by accident shortly after posting my query, and it provides the result I want, i.e. retaining the original motion.

FWIW there's nothing in the HandBrake documentation to make it clear that if you have interlaced source material and you want to encode it whilst retaining the original motion, you should deinterlace using "bob".

In order to play correctly on anything but an old CRT, a deinterlace filter will need to be invoked after decoding, so why go through this?

Well, since native MPEG-2 interlaced video plays on my plasma with its original motion, I assumed that the best way to encode via Handbrake would be to retain the interlace. Coming from a pre-flat-screen TV broadcast background, I automatically associated deinterlacing with "filmising" video-look video, I didn't realise it could be used to maintain video-style motion on progressive displays. Additionally, back when I was creating XviD AVI files, I'd encode them interlaced to retain the video motion.

[BradleyS]

No doubt, your natively progressive plasma employs a high quality bob-like deinterlacer.

With my similar background I often hear that deinterlacing destroys motion, which is a half truth; it really depends on the method used as you've discovered by bobbing. Since today all interlaced video is always played back progressively, to not deinterlace produces the worst of both worlds; reduced motion plus combing artifacts. Despite the obvious error in this approach, I still find "old video" guys like us who think this ugly output is somehow better because deinterlacing was a bad word historically. The mind boggles.

All that to say, kudos to you for trusting your good eyes instead of the old dogma, which is entirely irrelevant in the age of progressive displays!

[Deleted User 13735]

Your TV screen will deinterlace, but without any choice of the hardware method employed.
Your Monitor will not deinterlace natively; you must rely on a variety of software deinterlacers employed by the players themselves.
For web use, the upstream converters are dog****. Again, no choices.

Best way is decomb or bob (if your end delivery supports the frame rate).

[AVR2]

Thanks for the above help. One last question - what's the best way of converting bob-deinterlaced material back to interlaced for display on a CRT? For reasons that are too long and boring to explain, I ideally need to be able to do this

[Deleted User 13735]

Your hardware player / media center delivers compliant interlaced program through its analog outputs. It has to.