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cakuhnen
17th March 2018, 05:34
Hi all, i want to know how can i encode with x265 interlaced vídeo, i want to store interlaced, i know that this option --interlace=tff encode interlaced but i need to separate fields or i can encode with handbrake, ffmpeg and it does the separate fields automatic

Regards

CAK

Sharc
17th March 2018, 09:50
From the x265 doc (http://x265.readthedocs.io/en/default/cli.html):

HEVC encodes interlaced content as fields. Fields must be provided to the encoder in the correct temporal order. The source dimensions must be field dimensions and the FPS must be in units of fields per second. The decoder must re-combine the fields in their correct orientation for display.

Not sure which HW or SW player plays this correctly. For interlaced encoding I stick to x264/MBAFF.


You could try something like:

For encoding your interlaced source:
AssumeTFF()
separatefields()

now encode in x265 with --interlace tff


For interlaced playback:
Assumefieldbased()
weave()

foxyshadis
19th March 2018, 08:35
From the x265 doc (http://x265.readthedocs.io/en/default/cli.html):



Not sure which HW or SW player plays this correctly. For interlaced encoding I stick to x264/MBAFF.
Obviously all hardware plays it back correctly, that's one thing you can reliably count on hardware to support. HEVC interlaced is almost exactly the same as AVC PAFF, since MBAFF was removed. Software that supports both AVC interlaced and HEVC generally supports HEVC interlaced.

Sharc
19th March 2018, 14:22
.....Software that supports both AVC interlaced and HEVC generally supports HEVC interlaced.
Unless I am totally mistaken SW players like MPC-HC or VLC will normally (per default) play the fields (half height picture) at double rate. For
undistorted AR one has to force the correct (original) DAR during playback, or to set --sar 1:2 for encoding which will give a kind of bob-deinterlaced playback (with no control over the bobbing algo)

foxyshadis
20th March 2018, 06:50
Unless I am totally mistaken SW players like MPC-HC or VLC will normally (per default) play the fields (half height picture) at double rate. For
undistorted AR one has to force the correct (original) DAR during playback, or to set --sar 1:2 for encoding which will give a kind of bob-deinterlaced playback (with no control over the bobbing algo)

VLC is a horrible player that no one should use unless they have no alternative, its support for interlacing varies between barely-functional and "roll your own ffmpeg commandline," because none of the maintainers care about things real people care about. (IMHO, but I've tried and tried hard to make it work.) Even Windows Media Player supports interlaced reasonably, if the underlying splitter/decoder signals it.

The MPC family, MPDN, Kodi, Plex, GOM, and the rest of the half-decent Windows players all support either automatic or manual deint/bobbing, and you can choose your own quality level in most. Even in Linux, you shouldn't feel yoked to the VLC ghetto, you've got SMPlayer, mpv, Banshee, and I hear good things about Gnome Video.

nevcairiel
20th March 2018, 09:48
HEVC interlaced is not supported by any FFmpeg based player, since FFmpeg does not support it. It'll decode to half-height fields instead of a combined frame.
Just let interlacing die already. :)

Blue_MiSfit
20th March 2018, 20:24
I think there's a good chance the creation of new interlaced content will die with native UHD content, which will be encoded with HEVC and other new formats.

The enormous quantity of legacy content, however, means interlacing is here to stay :devil:! As long as there's support for it without damaging it, we should all be happy and move on with our lives :D

Sharc
21st March 2018, 17:00
Hmmm...., maybe I misread the x265 doc in post #2 (https://forum.doom9.org/showpost.php?p=1836607&postcount=2).
There is no need for an external field separation for interlaced sources. x265 is doing it internally when --interlace tff (or --interlace bff) is in the commandline. Correct?

sneaker_ger
21st March 2018, 17:08
The post you linked as well as the official documentation indicate the exact opposite, i.e. you do have to separate the fields beforehand.

But like said earlier by others playback as well as compression is a problem. I would avoid encoding interlaced HEVC completely. Also, correctly muxing the stream might pose a problem.

Sharc
21st March 2018, 17:15
Thanks much for clarification :)
It confirms my original understanding, but I thought that I may have missed something.

cakuhnen
24th March 2018, 05:36
The post you linked as well as the official documentation indicate the exact opposite, i.e. you do have to separate the fields beforehand.

But like said earlier by others playback as well as compression is a problem. I would avoid encoding interlaced HEVC completely. Also, correctly muxing the stream might pose a problem.

No problem at all, my PANASONIC HDTV play fine interlaced hevc encoded by x265

SeeMoreDigital
25th March 2018, 09:59
No problem at all, my PANASONIC HDTV play fine interlaced hevc encoded by x265Can you provide a sample?

benwaggoner
28th March 2018, 18:11
I think there's a good chance the creation of new interlaced content will die with native UHD content, which will be encoded with HEVC and other new formats.

The enormous quantity of legacy content, however, means interlacing is here to stay :devil:! As long as there's support for it without damaging it, we should all be happy and move on with our lives :D



Yes, UHD is ALWAYS progressive. We missed a great opportunity with ATSC standardization in the late 90’s; interlaced was ALMOST excluded from HD back then.


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