Quantcast Aspect Ratio, Source, Player, TV.. What a Mess! - Page 3 - digitalFAQ.com Forums [Archives]
  #41  
02-16-2005, 04:45 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by muaddib
We are talking about anamorphic... and that is not 4:3 but 16:9
Okay. You're right. The end.

Note: next time you will encode an anamorphic picture, tells to tmpgenc it is 16:9, and you want it 16:9 and good luck for the A/R of the output.
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  #42  
02-16-2005, 11:54 AM
muaddib muaddib is offline
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Quote:
Originally Posted by Dialhot
Okay. You're right. The end.
Okay. I see it. The end.

Quote:
Originally Posted by Dialhot
Note: next time you will encode an anamorphic picture, tells to tmpgenc it is 16:9, and you want it 16:9 and good luck for the A/R of the output.
Did you already try it? I did. Please, do yourself a test.

Beside that, in the beginning of this discussion, I just questioned why we have to set the source to 4:3 (like you said). I didn't say it was wrong or write. You answered me with " Anamorphic means 4/3". That is what I didn't agree. And as this "4/3" didn't mean the AR or the resolution, them I still not agree with that.
But we are going to nowhere with this... so, as you said, the end.
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  #43  
02-16-2005, 12:14 PM
Dialhot Dialhot is offline
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Quote:
Originally Posted by muaddib
Did you already try it? I did. Please, do yourself a test.
Yes I did, and I was sure you will say that you did test and not have any problem, because I know the reason of this. But continue... use 16/9, I don't mind.

Quote:
Beside that, in the beginning of this discussion, I just questioned why we have to set the source to 4:3 (like you said).
Because you have to. It is not because using 16/9 worked in the test you did that this is the correct setting. There is something else in settings of tmpgenc that makes the choice of 4/3 - 16/9 or whatever else (for the source I mean) completly void. I know it, you miss it, I will let you discover it by yourself and then you will understand why 16/9 was not the correct setting. Till then, do as you wish as long as your encodings give you satisfaction (this is the most important after all).

Quote:
Anamorphic means 4/3[/b]"
And I told after this something that you miss : "To follow your way of thinking then my statement has to be changed to "an anamporphic picture is ALWAYS something 16:9". All other proportions are first turned to 16:9 by adding black borders, then anamorphism is applyied on the 16:9 box (to become a 4:3 box). "

You can turn the idea as you want in your mind, for tmpgenc point of view your source is 4/3. period.

Quote:
That is what I didn't agree.
And I can live with you thinking this. Even if it is wrong. As I said, I can't explain it differently.
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  #44  
02-16-2005, 12:42 PM
drequena drequena is offline
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Don't mean to heat this debate but I want to learn, you know

Quote:
There is something else in settings of tmpgenc that makes the choice of 4/3 - 16/9 or whatever else (for the source I mean) completly void
Would this be "Video Arrangement Method" --> Center?

Tmpgenc help isn't very extensive on this topic but I understand that centering on the screen an image that's alerady anamorphic will result in a correct output aspect ratio wichever the source A/R selected.

Even Center (keep aspect ratio) should work as potentially needed bars would be already in place.. Of course, not shure about this..
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  #45  
02-16-2005, 12:51 PM
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Quote:
Originally Posted by drequena
Would this be "Video Arrangement Method" --> Center?
yes it is.

Quote:
Tmpgenc help isn't very extensive on this topic but I understand that centering on the screen an image that's alerady anamorphic will result in a correct output aspect ratio wichever the source A/R selected.
More exactly, whatever is not tagged with "keep aspect ratio" won't give a shit about what you set for source and target A/R.

Quote:
Even Center (keep aspect ratio) should work as potentially needed bars would be already in place.. Of course, not shure about this..
Try...

Note: to compare quiclkly the arrangement method, you can go in "Clip frame" (in advanced settings), in the second tab (video arrangement) you can change the method and see the impact on the preview directly.
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  #46  
02-16-2005, 02:06 PM
muaddib muaddib is offline
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Quote:
Originally Posted by Dialhot
But continue... use 16/9, I don't mind.
Relax man... I don't know why you are taking this personally. It's NOT. I just want to get it clear.

Quote:
Originally Posted by Dialhot
There is something else in settings of tmpgenc that makes the choice of 4/3 - 16/9 or whatever else (for the source I mean) completly void. I know it, you miss it, I will let you discover it by yourself and then you will understand why 16/9 was not the correct setting.
Oh, please "mystery man" (just kidding ), I know (well I guess) what you mean, and I didn't miss it.
But I think you did...

Quote:
Originally Posted by Dialhot
Till then, do as you wish as long as your encodings give you satisfaction (this is the most important after all).
It sure is! See... here is one more thing that we agree!

Quote:
Originally Posted by Dialhot
... for tmpgenc point of view your source is 4/3. period.
Now we are back to my original doubt... but I still don't know why you say that.


Quote:
Originally Posted by Dialhot
Quote:
Originally Posted by drequena
Tmpgenc help isn't very extensive on this topic but I understand that centering on the screen an image that's alerady anamorphic will result in a correct output aspect ratio wichever the source A/R selected.
More exactly, whatever is not tagged with "keep aspect ratio" won't give a sh*t about what you set for source and target A/R.
That’s exactly the reason that if you set 4:3 and “center” will not ruin your AR.
You are doing exactly what you said that I would do!
You set a wrong AR in the source and then you tell TMPG to ignore that setting.
Try to set "keep aspect ratio" and then encode two samples... one with 16:9 and other with 4:3.
Now tell me which one has the wrong aspect.
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  #47  
02-16-2005, 03:39 PM
kwag kwag is offline
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The basic rule I use is that I always use "Full Screen", and let AviSynth feed in the correct aspect to TMPEG.
That will guarantee that TMPEG won't try to do any corrections on the source, like if you set "Full Screen (keep aspect)", etc.

-kwag
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  #48  
02-16-2005, 04:04 PM
Dialhot Dialhot is offline
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Quote:
Originally Posted by kwag
That will guarantee that TMPEG won't try to do any corrections on the source, like if you set "Full Screen (keep aspect)", etc.
And that is the correct way to do because... tmpgenc designer completly screwed up the meaning of anamorphic.

If you do the test suggested by Muaddib, then "16:9" will have the correct aspect (and "4:3' is shrinked horizontally ). I never saw that on whatever video editing tool I used. (I mean the horizontal steching).

Muaddib is right (about tmpgenc) but the problem is that... tmpgenc does the same error than anyone that is a noob in video does : to make a confusion between 16:9 and anamorphic !

What they call "16:9" is in fact "16:9 anamorphic" (the exact word that should be used insteed of just "anamorphic").

And it was called "16:9 anamorphic" because it is not a 16:9 picture !

Anamorphic means 4:3. I can't change the definition of the word (anamorphic = "distorted image" you can check in whatever dictionnary you want). If anamorphic means 16:9, tell me in wich way it is distorted ?

Edit: I wonder what they call "2.21"
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  #49  
02-18-2005, 12:20 AM
muaddib muaddib is offline
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Quote:
Originally Posted by kwag
That will guarantee that TMPEG won't try to do any corrections on the source, like if you set "Full Screen (keep aspect)", etc.
Yes, that's the right way to do it! Not because TMPG screwed with anything, but because that's the way we want TMPG to work... as an encoder, not as an editor, for that we use AviSynth... as we know it is a much better editor.

Following this way o thinking of not letting TMPG do any corrections on the source, I think the best setting would really be "center" (without the "keep aspect ratio" of course). That's because if we set "Full Screen" and for some strange reason we screwed up with the script and didn't feed TMPG with the correct frame size, then TMPG will resize the source to fit the frame size we set. If we had used "center" TMPG would had not touched the source (just centered it), making it easier to detect the problem, especially if we are encoding a 4:3 fullscreen.
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  #50  
02-18-2005, 12:33 AM
muaddib muaddib is offline
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Quote:
Originally Posted by Dialhot
And that is the correct way to do because... tmpgenc designer completly screwed up the meaning of anamorphic.

If you do the test suggested by Muaddib, then "16:9" will have the correct aspect (and "4:3' is shrinked horizontally ). I never saw that on whatever video editing tool I used. (I mean the horizontal steching).

Muaddib is right (about tmpgenc) but the problem is that... tmpgenc does the same error than anyone that is a noob in video does : to make a confusion between 16:9 and anamorphic !
Oh Phil... you are really a hard one. You need to be right even when you say you are wrong!
Come on... Now is the TMPG designer that screwed up the meaning of anamorphic and committed a noob error?
No man, they didn't screw up with anything. That setting is doing exactly what it's supposed to do. That is setting the source aspect ratio. Just look at the name of the setting! It can't be clearer! It's called "Source aspect ratio".

So here comes the million dollar question... If we agree that all anamorphic streams have a 16:9 aspect ratio... How should we set the "source aspect ratio" setting of a source that is anamorphic?

Now about the "horizontal stretching" that you didn't understand... What you think TMPG was going to do if you say that you have a 4:3 aspect ratio source and you ask it to keep this aspect ratio when encoding a 16:9 frame?
It was going to do exact the same job of a widescreen TV (that is 16:9) when you say you want to play a 4:3 stream and keep the right aspect... That is put black bars on the sides to preserve the 4:3 aspect.

Quote:
Originally Posted by Dialhot
What they call "16:9" is in fact "16:9 anamorphic" (the exact word that should be used insteed of just "anamorphic").
Should I ask you to read the name of the setting again?
What they call 16:9 is 16:9 aspect ratio.

Quote:
Originally Posted by Dialhot
And it was called "16:9 anamorphic" because it is not a 16:9 picture !
Of course it's not a 16:9 picture. It's a picture that has a 16:9 aspect ratio!

Quote:
Originally Posted by Dialhot
Anamorphic means 4:3. I can't change the definition of the word (anamorphic = "distorted image" you can check in whatever dictionnary you want). If anamorphic means 16:9, tell me in wich way it is distorted ?
Oh no... are we going through this again Anamorphic means 16:9 aspect ratio!
It's distorted in a way that this frame (that we know doesn't have 16:9 dimensions) need to be distorted into a 16:9 box to be viewed correctly.
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  #51  
02-18-2005, 05:03 AM
incredible incredible is offline
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To clear this a bit up in an example of PAL:

We got physical DVD conform sizes of

- 720(704)x576
- 352x576
-352x288

Lets imagine the case of 704x576.
The physical size is 704x576, means finally a 4:3 (1.33:1) proportion on TV.

The main question now is WHAT is inside these 704x576, means whats the content of the image?

Do these 704x576 contain a full recognisable unsqueezed image content? Like this:
(dont take care of the green border its the overscan area)


Or do these 704x576 contain a full recognisable unsqueezed image content but with black bars? Like this:

(this image IS!! 4:3 out of a letterboxing from a 16:9 origin = black bars WITHIN the 4:3 image!)

All these images above do have a 4:3 aspect ratio. Why? because they are NON ANAMORPHIC, means NOT horizontally Squeezed in a significant way.

So when re-encoding these, we choose as Source 4:3 and also as target 4:3



Now lets assume the case IF we got an anamorphic image within our 704x576 pixels.


This is anamorphic, means horizontally squeezed, means it has to be stretched on TV (not in the encoder) by a factor of 1.333 horizontally, to obtain a perfect 1024x576 image proportion finally on a 16:9 TV/Beamer device

If I want to keep it that way, then I do choose in TmpgEnc as Source 16:9 and also as target 16:9, because I do keep the anamorphic 16:9 state.


What do I have to do IF I want to make an anamorphic Image to bekome a 4:3 one as IF I want to safe Bitrate for example?

Easy:
I do choose 16:9 as source as my source is anamorphic (squeezed) and choose 4:3 as target by keeping the aspect ratio.

This will result in a letterboxed 4:3, means a 16:9 image proportion within the effective 4:3 704x576 pixels:



Conclusion:
The encoder itself DOESN'T care whats within the 704x576! The encoder ONLY recognises the 704x576 as a total pixel area.
If in the encoder the option 16:9 as target is choosen (no matter if CCE, TmpgEnc, mencoder, Qenc etc) THEN this means that a 16:9 flag will be set in the header of the mpeg file while encoding. WHICH causes the playback device (SAP) finally to stretch (undistort) the encoding by a factor of 1.333 horizontally finally to match the 16:9 Image area of the TV/Beamer.
... And thats what Phil meant ...


Heres also some info about AspectRatios etc.
http://www.incredible.de.tf/aspectratios.html
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  #52  
02-18-2005, 06:02 AM
Dialhot Dialhot is offline
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All the problem comes from this :
Quote:
Originally Posted by incredible
(this image IS!! 4:3 out of a letterboxing from a 16:9 origin = black bars WITHIN the 4:3 image!)
[...]
I do choose 16:9 as source as my source is anamorphic (squeezed)
In these two sentenses, the word 16:9 is used for two different things ! The first one is the correct one "a 16:9 picture" is a picture that has a 16:9 A/R.
The second one is what I call a screwy stupid usage of the word "16:9" (done in tmpgenc and A LOT of noobs article) insteed of "16:9 anamorphic" or just "anamorphic".

I can repeat this for ever : an anamorphic picture is not 16:9, it is 4:3 and MUST be undistort to be seen as 16:9.
As Muaddib said "we know (it) doesn't have 16:9 dimensions". We... the humans. Not the computers nor the TV set. For them, as as long you do not tell them "this is a 16:9 frame", they treat and display them as 4:3
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  #53  
02-18-2005, 07:04 AM
incredible incredible is offline
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Quote:
Originally Posted by Dialhot
All the problem comes from this :
Quote:
Originally Posted by incredible
(this image IS!! 4:3 out of a letterboxing from a 16:9 origin = black bars WITHIN the 4:3 image!)
[...]
I do choose 16:9 as source as my source is anamorphic (squeezed)
In these two sentenses, the word 16:9 is used for two different things ! The first one is the correct one "a 16:9 picture" is a picture that has a 16:9 A/R.
The second one is what I call a screwy stupid usage of the word "16:9" (done in tmpgenc and A LOT of noobs article) insteed of "16:9 anamorphic" or just "anamorphic".
These two sentences quoted in the way you did above do not stand in context like I wrote it in my Post further above. These where Taken out of two different cases I did explain.

Quote:
Originally Posted by Incredible
(this image IS!! 4:3 out of a letterboxing from a 16:9 origin = black bars WITHIN the 4:3 image!)

All these images above do have a 4:3 aspect ratio. Why? because they are NON ANAMORPHIC, means NOT horizontally Squeezed in a significant way.

So when re-encoding these, we choose as Source 4:3 and also as target 4:3
In that explained case they is NO word used of "16:9" but "Letterboxing out of a 16:9" and I also explained that THIS case is 4:3 source to 4:3 reencoding as the source gots NO squeezed picture.

People do think IF they see a movie incl. black bars on top and bottom than that this is a case of 16:9 ... and it isn't.

4:3 = NOT squeezed horizontally (non-anamorph)
16:9 = Squeezed horizontally (anamorph)

And I dont know why we always do bring doubts about such facts again on top as so many threads already dealed with that where discussions and conclusions already have been made

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  #54  
02-18-2005, 07:27 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by incredible
4:3 = NOT squeezed horizontally (non-anamorph)
16:9 = Squeezed horizontally (anamorph)
Again NO !

4:3 - 16:9 and 16:9 anamorphic are THREE different things !

Ok, I drop it, do as you want. But do not ask yourself this :
"And I dont know why we always do bring doubts about such facts"

The doubt is created by the usage of a single word for two different things.

Note: I'm sure you know some 16:9 SAT TV broadcast channels (like new HDTV Euro1080). Are they anamorphic ?.
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  #55  
02-18-2005, 07:55 AM
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In an "encoder language" (and we are talking about encoding in here) 16:9 output means a SQUEEZED image including a 16:9 Stream-Header-Flag which lets stretch or letterbox the squeezed anamorph picture by the SAP to fit CORRECT a ....

16:9 TV proportion stretching horizontally means 1024x576px (seen digitally)
or ...
4:3 TV proportion squeezing vertically means 768x432 incl. adding black borders at top/bottom.

All ---16:9--- DVB broadcastings are broadcasted in a squeezed state! The DVBviewer appl. does show that flag in the Informationspanel and de-squeeze them like a SAP.
There do exist many 4:3 broadcastings (and movies seen in a whole) where a 16:9 effective moviearea was letterboxed into the 4:3 image = black borders.
AND THATS the confusion!
MANY MANY TV-Magazines do describe some Movies as broacasted in 16:9 but they are just 4:3 using black borders at top/bottom = a detail-fake.

16:9 regulary means a squeezed/anamorph image within the choosen resolution when encoding
4:3 means NON squeezed, so non anamorph

16:9 Letterboxed in 4:3 is a conversion-word misusage where the Image comes in effective non squeezed 4:3 incl black borders.

I do think very clear that we both do mean the same thing! As I also know all your other threads and skills about that in here.
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  #56  
02-18-2005, 08:22 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by incredible
In an "encoder language" (and we are talking about encoding in here) 16:9 output
FYI, we do not discuss about the output (for that at least, we all agree ), but about the input.

Quote:
All ---16:9--- DVB broadcastings are broadcasted in a squeezed state! The DVBviewer appl. does show that flag in the Informationspanel and de-squeeze them like a SAP.
All, including the HDTV Euro1080 ?

Quote:
16:9 regulary means a squeezed/anamorph image within the choosen resolution when encoding
4:3 means NON squeezed, so non anamorph
Again no... Or more precisely "in what you called 'encoder language' (this is a new thing ?) people regulary use 16:9 for saying anamorphic but it is a wrong usage".

Like the other misuse that you point just after :
Quote:
16:9 Letterboxed in 4:3 is a conversion-word misusage where the Image comes in effective non squeezed 4:3 incl black borders.
When you buy a LCD projector that is 16:9, it does not means that it can handles the squeezed picture. It does mean that it use a 16:9 matrix.
When you buy a 16:9 TV set, it does not have a "squeezed" screen, it has a rectangular 16:9 screen.
When you make a 16:9 screen for your projector, you do not buy a 4:3 piece of elastic material that you shrink horizontally. You buy directly a 16:9 material.

16:9 is one thing, 16:9 anamorphic is an other. And I'm sorry to continue to tell that 16:9 anamorphic is "a sort of" 4:3 picture.
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  #57  
02-18-2005, 08:54 AM
incredible incredible is offline
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Quote:
Originally Posted by Dialhot
Quote:
Originally Posted by incredible
In an "encoder language" (and we are talking about encoding in here) 16:9 output
FYI, we do not discuss about the output (for that at least, we all agree ), but about the input.
Thats what Im also was refering to in my examples more above
Quote:
Quote:
All ---16:9--- DVB broadcastings are broadcasted in a squeezed state! The DVBviewer appl. does show that flag in the Informationspanel and de-squeeze them like a SAP.
All, including the HDTV Euro1080 ?
Im not shure if 1080i mpeg2 streams do support the 16:9 flag if not then the 1080i stream ONLY can be broadcasted as 16:9 Letterboxed to 4:3 = a technical 4:3 Image proportion.
Quote:
Quote:
16:9 regulary means a squeezed/anamorph image within the choosen resolution when encoding
4:3 means NON squeezed, so non anamorph
Again no... Or more precisely "in what you called 'encoder language' (this is a new thing ?) people regulary use 16:9 for saying anamorphic but it is a wrong usage".
ahhh ... thats the way you want to explain ...
ok, if you see it like that THEN a 16:9 Stream is a squeezed Image so it fits in a 4:3 total technical image proportion like 704x576 (=768x576) ... which will be stretched finally on your 16:9 TV back to its real 1.78:1 state.

But anyhow .... in mpeg encodings 16:9 means regulary squeezed/anamorph ... thats a fact ... sorry but I dont want to push it more now.
Quote:
Like the other misuse that you point just after :
Quote:
16:9 Letterboxed in 4:3 is a conversion-word misusage where the Image comes in effective non squeezed 4:3 incl black borders.
When you buy a LCD projector that is 16:9, it does not means that it can handles the squeezed picture. It does mean that it use a 16:9 matrix.
When you buy a 16:9 TV set, it does not have a "squeezed" screen, it has a rectangular 16:9 screen.
When you make a 16:9 screen for your projector, you do not buy a 4:3 piece of elastic material that you shrink horizontally. You buy directly a 16:9 material.
A friend of mine who gots a 1024x768 effective px projector enjoys the capability of the projector that the incoming 16:9 mpeg stream component signal can be "stretched" in the projector technically out of 704x576 to 1024x576px where THESE will be send to the LCD/DLP panel.
If the projector is feeded via analogue component or svideo signal, then the projector deals with 625Lines at 50hz! If the projector will be feeded via RGB VGA connection (like via PC) then the effective resolution will be directly provided to the LCD panel, like 1024x768 at 75hz.
Quote:
16:9 is one thing, 16:9 anamorphic is an other. And I'm sorry to continue to tell that 16:9 anamorphic is "a sort of" 4:3 picture.
Shure as a squeezed! 16:9 anamorph image is within 704x576 (so technically in a 4:3 state incl a 16:9 flag).

Do set in CCE "16:9" and this means that the encoder gets the message that a squeezed picture input has to be encoded in a kept state where a 16:9 flag has to be included so the SAP "recognises" that he deals with a 16:9 anamorph input where the result is a letterboxing to 4:3 or a DIRECT squeezed deliverence to the TV set is given where the TV set stretches the signal to its 16:9 image state finally.
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  #58  
02-18-2005, 09:04 AM
incredible incredible is offline
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(related to 1080i DVB broadcasting):

STOP! Youre right! (in case of HDTV) as the resolution of HDTV is

1920x1080i

and

1280x720p

So thats an "effective image of 16:9"-encoding, means the new HDTV Format.

BUT all my explanations where based on the encoding techniques and defenitions of NON!-HDTV where the Output mainly is purposed for 625/50Hz devices playback at 14.769 Hz @ 52.000 = 768x576(seen digitally). HDTV Devices do not follow those known analogue Playback devices signal technique as theyre capable to show digital input directly.
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  #59  
02-18-2005, 09:47 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by incredible
So thats an "effective image of 16:9"-encoding, means the new HDTV Format.
I guess when time will come to encode such sources, a new word will appear in "encoder language" (16:9 HDTV may be ?)

All that because "encoders" can't speak basic english...
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  #60  
02-19-2005, 02:04 AM
muaddib muaddib is offline
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Quote:
Originally Posted by incredible
All these images above do have a 4:3 aspect ratio. Why? because they are NON ANAMORPHIC, means NOT horizontally Squeezed in a significant way.

So when re-encoding these, we choose as Source 4:3 and also as target 4:3
That's perfect.

Quote:
Originally Posted by incredible
This is anamorphic, means horizontally squeezed, means it has to be stretched on TV (not in the encoder) by a factor of 1.333 horizontally, to obtain a perfect 1024x576 image proportion finally on a 16:9 TV/Beamer device

If I want to keep it that way, then I do choose in TmpgEnc as Source 16:9 and also as target 16:9, because I do keep the anamorphic 16:9 state.
That's also perfect, and exactly what I was trying to show to Phil. While in the middle of it we felt into a discussion of what is anamorphic.

Quote:
Originally Posted by incredible
What do I have to do IF I want to make an anamorphic Image to bekome a 4:3 one as IF I want to safe Bitrate for example?
Easy:
I do choose 16:9 as source as my source is anamorphic (squeezed) and choose 4:3 as target by keeping the aspect ratio.
This will result in a letterboxed 4:3, means a 16:9 image proportion within the effective 4:3 704x576 pixels:
Again perfect! But just to clarify, that's not what we used to do, because that would make the encoder act as an editor. We are used to feed the encoder with the 16:9 active image proportion within the effective 4:3 already edited. Then we would encode 4:3 to 4:3.

To complete there is also one more (strange?) possibility.
What do I have to do IF I want to make a 4:3 fullscreen image to become a 16:9 one?

Easy:
I do choose 4:3 as source, as my source is fullscreen and choose 16:9 as target by keeping the aspect ratio. (<-- that is what Phil was doing setting the source as 4:3)
This will result in a "letterboxed" 16:9 with black bars at the sides, means a 4:3 image proportion within the effective 16:9 image. This image still has 704x576 pixels. Do you know why? Because in the end, this frame is an anamorphic picture! That has to be finally stretch (undistort) horizontally to match the 16:9 Image area of the ws TV/Beamer.

BTW, setting the encoder this way, we are also using it as an editor. We can easily do that with an AVS script and feed the encoder with the 4:3 active image proportion within the effective 16:9 anamorphic frame already edited, and encode a 16:9 to 16:9.
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