Progressive ?

[pippas]

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

Sadly, I don't have a Blue Peter Badge ... I'm not one of the chosen few.....

The Quo You Tube clip downloads as a very strange item..... a progressive mp4, with frame dimensions of 600 x 480 (5:4) -- and a variable frame rate! ... Oh, and a constant bit rate.. Goodness knows what You Tube did to the original to arrive at that....

Could be the mediainfo file that is up the creek I suppose?....

Edit: ... No, it's definitely 600 x 480 and You Tube have made a pig's ear of de-interlacing it. (See attached frame capture).
I'm not surprised they don't want interlaced footage!

[DB83]

Neither do I

But, of course, when interlaced footage is resized on the vertical it is not going to look good on close inspection. The 5:4 obviously comes from the 720*576 original.

I kinda guess this does indeed prove the point that you do need to force DAR with square pixels and de-interlace.

Only except to my one good eye, in real time, the yt footage is passable and your average Jo will not know the difference.

[manono]

That clip is from 2009 and things have changed since then. While they didn't use to take a DAR into account, I believe they do these days. You should be able to upload a 720x480/576 MPG or VOB and have it resized and reencoded to the correct square pixel aspect ratio. You still should provide them with a progressive source.

The guy that uploaded the clip could still force the right playback aspect ratio by adding an aspect ratio tag.

[Tafflad]

Guys ... on that last comment I know nothing about "adding an aspect ratio tag"

How where do you do that ... can you give an example of how to do this.

[manono]

You could easily have searched it out yourself, but here you go:

https://support.google.com/youtube/answer/146402?hl=en

It's not 720x480 so I'm not 100% sure it'll work in this case, but if the tag works to output 4:3 for any source, we can hope so. The problem is that YouTube doesn't have a 576p resolution, with 480p and 720p and nothing in between.

[pippas]

You could easily have searched it out yourself, but here you go:

https://support.google.com/youtube/answer/146402?hl=en

I already linked to that exact page in post #27...... I guess folk read these threads pretty selectively?...

Looks like I need to 'up my profile' a little bit, to get my posts read at all. Not a lot of point in bothering to spend time looking up specific references and suggestions, if they just get ignored anyway?..

I'll try one more time......LOOK GUYS , IT'S QUITE STRAIGHT FORWARD.....DE-INTERLACE AND RESIZE YOUR CLIPS TO HAVE SQUARE PIXELS, BEFORE YOU UPLOAD TO YOU TUBE...THAT WAY THEY WILL MAKE LESS OF A MESS OF YOUR FOOTAGE, WHEN THEY CONVERT IT...SIMPLES!

Even something that obvious will still probably get ignored ...

Hey-ho..

[manono]

I already linked to that exact page in post #27...... I guess folk read these threads pretty selectively?...

That was directed at me? I admit I didn't read the entire thing before answering and if I did read your post earlier, I didn't remember it. It seems to me Tafflad is the one that should have paid attention to what you wrote before, and not I. Of my over 1000 videos on YouTube, all are already square pixel and progressive. You're preaching to the choir.

[pippas]

That was directed at me? I admit I didn't read the entire thing before answering and if I did read your post earlier, I didn't remember it. It seems to me Tafflad is the one that should have paid attention to what you wrote before, and not I. Of my over 1000 videos on YouTube, all are already square pixel and progressive. You're preaching to the choir.

No, not directed at you specifically -- more at myself really for not realising that people simply don't read much of the detail in a thread - especially once it gets too long.
Looking up URLS which offer specific details on a query,and then linking to them from within the text often seems to get ignored..

So I thought I'd try 'shouting' the blunt message instead

[Tafflad]

As requested by DB83
Uploaded 3 clips to Youtube for comparison of how they look on a streaming site

Original sample - This is the 720x576 DV file with 5:4 DAR (incorrect it was 4:3)
https://youtu.be/HTStSSk4n2U

De-interlaced - same file de-interlaced
https://youtu.be/kweQIU-qv6E


De-interlaced & resized to 768 x 576 with 4:3 DAR
https://youtu.be/XC8STM_AIeM


Would welcome your comments as to how you evaluate these 3 clips.

[DB83]

I guess you de-interlaced without separating the fields first. So the net result is interlacing artifacts.

But I am crap with avisynth so I'll leave to the experts.

[Tafflad]

You could easily have searched it out yourself, but here you go:

https://support.google.com/youtube/answer/146402?hl=en

It's not 720x480 so I'm not 100% sure it'll work in this case, but if the tag works to output 4:3 for any source, we can hope so. The problem is that YouTube doesn't have a 576p resolution, with 480p and 720p and nothing in between.

apologies for that ... assumed it was something that needed to be done in VD ..... didn't realise it was at Youtube end.

[Tafflad]

I guess you de-interlaced without separating the fields first. So the net result is interlacing artifacts.

But I am crap with avisynth so I'll leave to the experts.

Anybody care to advise on that .... I followed text on QTGMC page and simply used a 3-line script

AVIsource("E:\Test\sample.avi")
ConvertToYV12()
QTGMC(Preset="faster")



what else do I need to do to carry de-interlace properly ?

[Brad]

If your source is anything other than YV12, that script will mangle the chroma. You would need ConvertToYV12(interlaced=true).

But with PAL DV, that convert line is doing nothing if your decoder isn't upsampling.

Current versions of QTGMC don't require YV12 input, anyway.

[Tafflad]

If your source is anything other than YV12, that script will mangle the chroma. You would need ConvertToYV12(interlaced=true).

But with PAL DV, that convert line is doing nothing if your decoder isn't upsampling.

Current versions of QTGMC don't require YV12 input, anyway.

I had been adding ConvertToYV12 as when testing script on WMP it would play only audio - no video unless I added it.

I am a newbie on de-interlacing (freely admit)

Is your line: ConvertToYV12(interlaced=true) not what I need to add .. you were just showing that I needed to include the 2nd part if using.

What do I need to add to 'separate fields' correctly.
Qucik Googling some say use seperatefields or Assume BFF() keen to learn

[Brad]

I don't know what DB83 is referring to.

You should be able to remove the ConvertToYV12 line and use AVIsource("E:\Test\sample.avi",pixel_type="YV12"). You may need to install a better DV decoder if this line doesn't work.

[jagabo]

Your original sample is not 5:4 DAR, it's 4:3 DAR.

DAR = FAR * SAR

DAR = display aspect ratio, the final shape of the displayed picture
FAR = frame aspect ratio, the ratio of the frame dimensions
SAR = sampling aspect ratio, the AR of individual pixels*

Original sample was deinterlaced by Youtube and rendered with the correct 4:3 DAR. It looks like the container/codec you used in De-interlaced didn't not properly flag the DAR or SAR so Youtube rendered it at the FAR, 5:4. The Deinterlaced and Resized video rendered with the correct DAR, 4:3.


* SAR isn't really the aspect ratio of individual pixels, it's the relative distance between samples on the X and Y axis. Technically, pixels are dimensionless dots.

[Tafflad]

I don't know what DB83 is referring to.

You should be able to remove the ConvertToYV12 line and use AVIsource("E:\Test\sample.avi",pixel_type="YV12"). You may need to install a better DV decoder if this line doesn't work.

Tried that still audio only on WMP (video OK on VD)

[DB83]

I don't know what DB83 is referring to.

You should be able to remove the ConvertToYV12 line and use AVIsource("E:\Test\sample.avi",pixel_type="YV12"). You may need to install a better DV decoder if this line doesn't work.

Like I said, my knowledge on avisynth could be written on the back of a postage stamp and there would still be room for 'War and Peace' as well

It's just that I see over worst interlacing artifacts after de-interlacing. But, maybe, part of that could be down to yt re-sizing and the earlier suggestion was to re-size to 640*480 as well to take one element out of yt's hands.

[Tafflad]

Your original sample is not 5:4 DAR, it's 4:3 DAR.

DAR = FAR * SAR

DAR = display aspect ratio, the final shape of the displayed picture
FAR = frame aspect ratio, the ratio of the frame dimensions
SAR = sampling aspect ratio, the AR of individual pixels*

Original sample was deinterlaced by Youtube and rendered with the correct 4:3 DAR. It looks like the container/codec you used in De-interlaced didn't not properly flag the DAR or SAR so Youtube rendered it at the FAR, 5:4. The Deinterlaced and Resized video rendered with the correct DAR, 4:3.


* SAR isn't really the aspect ratio of individual pixels, it's the relative distance between samples on the X and Y axis. Technically, pixels are dimensionless dots.

Just looked at media info for the files

Original sample was 4:3
After it had been de-interlaced with QTCMG the saved file now shows as 5:4
When it was resized it is back to 4:3

[jagabo]

After it had been de-interlaced with QTCMG the saved file now shows as 5:4

You didn't flag the SAR or DAR in the codec or container so Youtube used the FAR as the DAR.

[Tafflad]

The file prior to de-interlacing was 4:3 .. after de-interlacing was 5:4
The mediainfo shows that .. before I upload to Youtube
"You didn't flag the SAR or DAR in the codec "

... is this a setting in VD ? (this is why I'm in Newbie section)

I saw the post about https://support.google.com/youtube/answer/146402?hl=en
and realise I could have set the flag to yttretch=4:3

Though I assume your comments refers to fixing it at file point of file encoding.

[manono]

Would welcome your comments as to how you evaluate these 3 clips.

Just right-click the YouTube screen and hit 'Stats for nerds' to find out the resolution YouTube used for them.

And if the 'Original sample' was interlaced, then I guess I was wrong about YouTube not deinterlacing videos these days. I would still do it myself, though, using QTGMC.

[Brad]

YouTube only does single-rate deinterlacing, and as noted downsizes 576p to 480p.

IMO all of this: the AR, the frame rate, and the resolution, could be solved by deinterlacing+resizing to 720p, 1080p, or even higher prior to uploading. (At least, I think they support 50fps. I know they do 60fps.)

[jagabo]

"You didn't flag the SAR or DAR in the codec "

... is this a setting in VD ?

AVI doesn't really support SAR/DAR flags. The DV stream in an AVI does have an AR flag and most editors/converters/players recognize the flag. You set the DAR flag in the DV encoder's settings, cedocida for example:



Some other codecs support it but programs may not respect it. This is why everyone keeps saying you should resize to square pixels if you can't control the downstream processing and playback environment.

[Tafflad]

Thnx for that.

Square pixels for on-line it shall be.

Going back to post #16 .... the workflow was:
-De-interlace
-Resize from 720 x 576 to 768x576 to get square pixels
-Deshaker for stabilisation

Am I right that no benefit/need in changing to square pixels for 'Deshaker' processing, was purely to suite on-line streaming.

Just thinking it would be better to apply DeShaker first as that will lose me some borders ... and then resize the output rather than having to resize twice ?

[manono]

-Resize from 720 x 576 to 768x576 to get square pixels

Once again, since there's no 576p on YouTube you'd be better off either downrezzing to 480p or uprezzing to 720p. And if your source is interlaced, in order to keep the fluidity of movement you might be better off upscaling to 720p using AviSynth's nnedi3_rpow2. At that resolution you can get 50fps out of it. I think.

[Tafflad]

By 720p do you mean uploading as a widescreen video as 1280 x 720
Or 'do you mean resizing to 960 x 720

[manono]

By 720p do you mean uploading as a widescreen video as 1280 x 720
Or 'do you mean resizing to 960 x 720

I mean upscaling to the same aspect ratio as the source. If it's a 1.33:1 ratio video then 960x720, yes.

Both resolutions you gave are 720p (once made progressive).

[Tafflad]

I thought I was getting things right in my head .... then 2 steps back.
Took my DV full capture original as detailed previously is 720 x 576 25fps DAR 4:3
Ran small Avisynth script to De-interlace, saved as GV Lossless

Resulting files is now 720 x 576 50 fps DAR 5:4

Why has the DAR changed, is this normal with GV Lossless ?

[jagabo]

The DAR has not changed, the information about it has been lost. As I told you before, the AVI container and most codecs used in it don't support SAR/DAR flags. In the absence if SAR/DAR information programs assume square pixels -- meaning 5:4 in the case of a 720x576 frame. And also again -- that's why everyone is telling you to resize so that DAR = FAR.