Progressive ?

[Tafflad]

This is an information question.
In a recent post it was discussed that interlaced source should be left interlaced during processing if going to be watched on a TV …….. but when these sources are watched on a PC they often do not view correctly unless you manually change field order.

When I produce video clips they are often viewed on TV and/or PC ……….. now typically when a PC version I render out in progressive … is this the best option ?

[pandy]

This is an information question.
In a recent post it was discussed that interlaced source should be left interlaced during processing if going to be watched on a TV …….. but when these sources are watched on a PC they often do not view correctly unless you manually change field order.

When I produce video clips they are often viewed on TV and/or PC ……….. now typically when a PC version I render out in progressive … is this the best option ?

You can't perform processing for interlaced video without deinterlacing - after processing it is up to you to re-interlace video or to keep it progressive (and if progressive then with full or half fps).

[smrpix]

You can't perform processing for interlaced video without deinterlacing - after processing it is up to you to re-interlace video or to keep it progressive (and if progressive then with full or half fps).

Depends on the processing. Color correction, for one, requires no deinterlacing

[Tafflad]

I certainly didn't de-interlace .... but all I did was cut, and colour correct in VD then drop into Vegas ..... did a whole load of editing in there.

In any event what about original Q ... what is best for sharing interlaced or progressive ?

As was found interlace would not play properly unless I manually changed filed order ............. want to be able to share files that just 'play'

[jagabo]

colour correct in VD

If it was interlaced YV12 video VirtualDub probably screwed up the chroma channels.

In any event what about original Q ... what is best for sharing interlaced or progressive ?

On native interlaced media like DVD? Usually interlaced. On progressive streaming sites like Youtube? Progressive.

[pippas]

This is an information question.
In a recent post it was discussed that interlaced source should be left interlaced during processing if going to be watched on a TV …….. but when these sources are watched on a PC they often do not view correctly unless you manually change field order.

When I produce video clips they are often viewed on TV and/or PC ……….. now typically when a PC version I render out in progressive … is this the best option ?

The advice you receive here about best interlacing practice will be excellent advice -- there are some very expert forum members --but there is an element of 'silk purse and sows ear' about low quality interlaced footage.....
You can't expect really good quality form a fairly poor quality source, so following best 'standard' practice may just limit your options a little.....

Take the clip you uploaded attached to this post. I would have looked at that material and decided that the most important aspect would be to try and stabilise the figure.... after all it is all about him!
And to do that I would de-interlace, resize for square pixels, and convert the file to an intermediate format at the start of the procedure.
Then try and stabilise, crop etc that new progressive file. (I've attached a short extract of your file to this post to show you what I mean).

The end result would then play on most PC players without any concern about de-interlace presets or AR flags etc..

To replay that file on a TV would of course require a media player (you couldn't make a compliant DVD out of it, for example).

If you are keen to continue using DVDs for your TV replay, then of course you will be constrained by very specific requirements of the DVD format, and already interlaced footage is probably best kept for DVD replay.

But if - like a lot of folk - you are perhaps thinking of moving on from DVDS for TV replay, then your options are much wider, format wise, and you should only need to keep one file for both PC and TV replay....

Just my 2 cents.....

[Brad]

As was found interlace would not play properly unless I manually changed filed order

That shouldn't be necessary if you're encoding to an interlaced format that can be flagged (i.e. not AVI).

[Tafflad]

colour correct in VD

If it was interlaced YV12 video VirtualDub probably screwed up the chroma channels.

In any event what about original Q ... what is best for sharing interlaced or progressive ?

On native interlaced media like DVD? Usually interlaced. On progressive streaming sites like Youtube? Progressive.

What about when you simply create say an H.264/MPEG-4 file to share ?

Just trying to get my options right

Mainly I share using youtube / facebook ... or Vimeo for HD

[Tafflad]

This is an information question.
In a recent post it was discussed that interlaced source should be left interlaced during processing if going to be watched on a TV …….. but when these sources are watched on a PC they often do not view correctly unless you manually change field order.

When I produce video clips they are often viewed on TV and/or PC ……….. now typically when a PC version I render out in progressive … is this the best option ?

Take the clip you uploaded attached to this post. I would have looked at that material and decided that the most important aspect would be to try and stabilise the figure.... after all it is all about him!
And to do that I would de-interlace, resize for square pixels, and convert the file to an intermediate format at the start of the procedure.
Then try and stabilise, crop etc that new progressive file. (I've attached a short extract of your file to this post to show you what I mean).

But if - like a lot of folk - you are perhaps thinking of moving on from DVDS for TV replay, then your options are much wider, format wise, and you should only need to keep one file for both PC and TV replay....

Just my 2 cents.....

I was just getting concerned that 'my' sample for example was poor unless I changed filed order on VLC .. but maybe that was just an anomaly.

To avoid changing focus of this Q ... I'll ping you a separate Q on what you did if that is OK

[DB83]

IIRC (and we are talking of the same clip), you did not change field-order in VLC - VLC does NOT do that (can only be done in an editor or avisynth and re-encode).

You actually de-interlaced the footage in real time. So you got rid of the lines you thought were bad but were actually normal.

[Tafflad]

I followed your advice last time:
"Play the clip in VLC. Set Video >> Deinterlace to on or automatic"

[DB83]

Ok. So that does NOT reverse field-order.

Reverse field-order is when a video is shot/captured as 'top-first' but re-encoded as 'bottom-first' in error.

And as I said elsewhere the term 'progressive' is inter-changeable with 'de-interlaced'. Playing a video in VLC with that setting still leaves the video interlaced. It is only the viewing that is changed.

[Tafflad]

That is what I was trying to explain at beginning (badly) ... I want to Render such that it will play in whatever player the user wants without having to set 'interlace' settings or similar.

Looks like answer in to go progressive.
Only use Interlaced if I'm creating a DVD.


Wonder what happens if you upload an interlaced video to Youtube/Vimeo ... do they convert to progressive ?

[DB83]

That is/was as explained to you. You create according to your target. For web-based, you create progressive but for dvd you leave field-order as is.

I do not know about Vimeo but Youtube re-encodes regardless. I have uploaded interlaced SD source to YT in the past and no harm, in my eyes, was done. But YT has changed since then so that may not be the case any more.

[pandy]

You can't perform processing for interlaced video without deinterlacing - after processing it is up to you to re-interlace video or to keep it progressive (and if progressive then with full or half fps).

Depends on the processing. Color correction, for one, requires no deinterlacing

Yes signal level adjustment and similar operations can be performed without deinterlacing, something more complex - deinterlace is mandatory step before proper processing.

Most services (recoding type) ignore interlace and assume progressive source. YT is full of movies encoded interlace as progressive.

[Tafflad]

And to do that I would de-interlace, resize for square pixels, and convert the file to an intermediate format at the start of the procedure.
Then try and stabilise, crop etc that new progressive file. (I've attached a short extract of your file to this post to show you what I mean).

.....

Your sample was a significant improvement .... looking into what you advised you did (via my PM request)

-De-interlace using internal deinterlace filter....Yadif algorithm - Double frame rate - lower field first

-Resize from 720 x 576 to 768x576 to get square pixels (filter mode Lanczos3 - aspect ratio disabled)

-Deshaker for stabilisation..


Could I ask for a bit more information on step 2.

Why do you need the change to square pixels ? I know it would get it to 4:3 aspect ration - is that the reason, or is it better to have square pixels for 'streaming sites'

[DB83]

Just my 2 cents on the clip posted in reply #6 (did not check this before)

I have my doubts if stabilisation is appropriate here. In my eyes it gives a re rather un-natural effect to the action in the surf (Is that you Rick ? ). Also the side-effect of the stabilisation means that the edges have to be cropped away. That then means another resize of the video and loss of clarity (even if it is small). And the crop is on the vertical so that does mean a de-interlace even if the OP did not want it.

[Tafflad]

It's the shimmer/ghost image I want to lose, which you mentioned previously is typical interlaced VHS video. It may be that I will not 'De-Shake' I'll try some comparisons De-interlacing, De-shaker and De-interlace + Deshake.

Using QTGMC will allow me to clean up noise and apply sharpening within single filter.

I remember someone posted a short Avisynth script to put to versions of an avi file side by side, have to see if I can find that. (wasn't you who provide it was it ?)

[jagabo]

It's the shimmer/ghost image I want to lose

And in your other thread:

yes ... almost like an out of sync second image

That's because it is an out of sync second image. Each frame of interlaced video contains two half images (called fields), taken at two different points in time (1/50 second in PAL, 1/30 second in NTSC). One half image is in all the even numbered scan lines, one in all the odd numbered scan lines. Double frame rate deinterlacing, like Yadif(mode=1) or QTGMC(), turns each of those half images into a full image, doubling the frame rate.

[DB83]

Ok. But I thought we had that covered.

De-interlace (for web) and it vanishes. *
Leave as interlaced for dvd and it vanishes when played on a tv (that does the de-interlacing for you)

There might have been an issue with the first version of your sample since you had converted the dv (which has an AR of 4:3) to lagarith which does not. Then you have to physically have to put the AR in to the file or resize to 768 * 576 and adjust to square pixels.

* Try this with the dv sample. Upload this un-touched to Youtube. How does it then look. ?

[Tafflad]

Will try some out 2morro

[jagabo]

Ok. But I thought we had that covered.

Yes, but Tafflad didn't seem to understand that there actually are two separate pictures in each frame.

[pippas]

Could I ask for a bit more information on step 2.
Why do you need the change to square pixels ? I know it would get it to 4:3 aspect ration - is that the reason, or is it better to have square pixels for 'streaming sites'

As I explained in my PM, I'm merely following the path that suits my requirements, and others will have different views (as you can see)....
This being the internet, you will have to make your own mind up which way of doing things suits you best....

I have no interest in interlaced footage, or video files with non square pixels. By eliminating both of those early on in my workflow I avoid totally the need for all players to de-interlace my footage 'nicely'....or any need to rely on players reading software non-square pixel 'AR flags' correctly, to ensure that clips are presented with the proper aspect ratio.

Taking that approach requires processing the video in a way that - some will say - detracts from producing the 'best' quality output file.

Personally, I find de-interlacing, resizing and working with a progressive, 'intraframe', square pixel intermediate file suits me best.... Others may not agree of course.

I suspect the best advice is probably to try both approaches with some short clips, and make your own decision on what suits you best..

[Tafflad]

Ok. But I thought we had that covered.

Yes, but Tafflad didn't seem to understand that there actually are two separate pictures in each frame.

I do understand Interlaced is 2 alternate frame. ( Good old analogue TV)
I am only talking now about producing progressive files for on-line viewing ...... therefore as previously advised I will de-interlace.

My source is DV (non-square pixel) and 720x576 which is not 4:3 ... hence my Q above ....... Pippas converted to 768 x 576 which is 4:3

I was just trying to understand ... for 'correct' progressive files do I need to convert to square pixels ... (after de-interlacing) or can I simply de-interlace and no need to resize.

[jagabo]

for 'correct' progressive files do I need to convert to square pixels ...

You don't have to. You can set the SAR or DAR flags at the codec or container level. But not all players obey the flags. I don't know how Youtube handles it. It's safest to resize yourself to the correct DAR.

[DB83]

^^ Still confused.

DV IS 4:3. Don't believe me then just check your footage in mediainfo (unless that do lie to me). It is the lagarith that 'squares' the pixels to 720*576 or 5:4.

It has already been stated that there is a ton of interlaced stuff on YT. Just upload that short DV clip and see how it looks with your eyes. By all means share the link so we can all have an opinion about it.

[pippas]

THIS PAGE will give you recommendations from You Tube itself. As you can see, it specifically advises against uploading interlaced footage (last comment in the 'Frame rate' section) and gives recommended frame sizes for 'fitting the player perfectly'.....
There is also advice on adding 'formatting tags' to correct non-square pixel videos, so at least You Tube should display them correctly when these 'flags' are added, even if other players won't necessarily do so....If you make your videos with square pixels, you don't have to worry about the 'flags' at all.....

As I say, these are just my own views on this....

[DB83]

Ok. But it does not say that you must NOT upload interlaced.

Now I have not done this for a long time and youtube, as I said earlier, is somewhat different now, but I link to a clip which, in the best Blue Peter tradition, (you will have to be a Brit to understand this) I made a little earlier.

Certainly the original capture was interlaced @ 720*576 mpeg2. I can not think I would have exported from the Ulead editor (after the enhancement) in to anything else. Unfortunately can not put my hands right now on the original.

https://www.youtube.com/watch?v=3HOmtVAFEGs

[jagabo]

Certainly the original capture was interlaced @ 720*576 mpeg2. I can not think I would have exported from the Ulead editor (after the enhancement) in to anything else. Unfortunately can not put my hands right now on the original.

https://www.youtube.com/watch?v=3HOmtVAFEGs

But encoded interlaced and containing interlaced frames are two separate matters. Any video can be encoded interlaced. That is a matter of how the codec treats the video internally. Interlaced frames contain two different pictures and will show comb artifacts wherever there is motion.

Some codecs/containers have explicit interlaced flags, others don't. So even if you uploaded an interlaced MPG video and Youtube recognized it as interlaced and deinterlaced it, Youtube may not recognize other containers/codecs as interlaced. I've seen many videos at Youtube with comb artifacts.

[Tafflad]

Ok. But it does not say that you must NOT upload interlaced.

Now I have not done this for a long time and youtube, as I said earlier, is somewhat different now, but I link to a clip which, in the best Blue Peter tradition, (you will have to be a Brit to understand this) I made a little earlier.]

I actually have a Blue Peter badge

good old clip of Francis Rossi