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-   -   Resize 640x480 non-anamorphic to 704x480 anamorphic (http://www.digitalfaq.com/archives/encode/13728-resize-640x480-anamorphic.html)

Icarus3000 08-05-2005 11:49 AM

Resize 640x480 non-anamorphic to 704x480 anamorphic
 
I want to insert some video clips that are 640x480 (non-anamporphic, 4:3 aspect ratio) into a larger video that is 704x480 anamorphic.

This is my logic on how to go about doing this, I'll test it out this weekend, but if I am totally off base, can someone let me know earlier :wink:

1. I want the final horizontal resolution to be 704 pixels, but since the source material is 4:3, I need to start of by resizing (squishing) the horizontal resoltion of the original from 640 to (704 X (4/3)/(16/9))=528.

2. Then add borders on the left and right to increase vertical resolution to 704. Do this by adding borders of (704-528)/2=88 to each size.

3. Finally when I encode the video, encode it as 16:9 anamorphic.

Questions:

a) Is my understanding of how to do this correct?
b) Will this script do what I described above:
Lanczosresize(704,480)
Addborders(88,0,88,0)

Please let me know if I am going about this the right way. Even if what I described above will work, if there is a better way to accomplish my goal, I am open to any suggestions.

Thanks!
Icarus

Dialhot 08-05-2005 12:13 PM

You're almost right.
You forget that the borders are added to the picture so you can't resize to 704 then add 88+88 px as borders. You have to resize 528.

Note: I did not do any math, I just opened Fitcd, enterd all the data you gave, and here comes the result :

Code:

LanczosResize(528,480,0,0,640,480)
AddBorders(88,0,88,0)

A lot simplier, is it ? :D

Note : your resulting picture will be very strange, with large borders on the sides. 8O

Icarus3000 08-05-2005 12:25 PM

Thanks Phil!

:oops: I mis-typed - I knew I should have had the resize(528,480).

But, are you sure I need (528,480,0,0,640,480)?

I thought the last numbers are there to tell the encoder to keep the same aspect ratio. Don't I need to change the aspect ratio to "squish" the video and create egg-heads at this point before adding the left & right borders?

It's a short clip I am testing, so I can try it both ways.


Quote:

your resulting picture will be very strange, with large borders on the sides.
I know.... but I wanted to make smooth transitions between this video and the rest of the video, and the clips I am adding are very short (~30 seconds), so I don't mind so much. Besides, doesn't all 4:3 material have large borders on the side when viewed on a widescreen TV?

Prodater64 08-05-2005 12:28 PM

From 640*480 1:1 not anamorphic to 704*480 anamorphic, with overscan (resizing) = 2, MovieStacker would give:

LanczosResize(448, 448, 0, 6, 640, 468)
AddBorders(128, 16, 128, 16)

and without overscan:

LanczosResize(480, 480, 0, 6, 640, 468)
AddBorders(112, 0, 112, 0)

Dialhot 08-05-2005 12:33 PM

Quote:

Originally Posted by Icarus3000
But, are you sure I need (528,480,0,0,640,480)?

You do not it but these values are hamless, as there are the default values avisynth will use if you not type them. Fitcd always gives the 6 values even when they are meaningless.

Quote:

I thought the last numbers are there to tell the encoder to keep the same aspect ratio.
Not at all, the are use to combine a crop and a resize.
(0,0) are the coordinates of the upper left corner and (640,480) the eight and width of the cropped rectangle. Here they are useless because (0,0)-(640,480) represent the whole source.

But if you want to crop 10 pixels from each sides before to resize you will use (10,10) and (620,440).

Quote:

Besides, doesn't all 4:3 material have large borders on the side when viewed on a widescreen TV?
Not if automatic zoom mode is activated on the TV that will switch the screen to "normal 16:9" to "zoomed 4:3" according to what you are looking at.

Dialhot 08-05-2005 12:36 PM

Quote:

Originally Posted by Prodater64
MovieStacker would give:
LanczosResize(480, 480, 0, 6, 640, 468)
AddBorders(112, 0, 112, 0)

You don't use it correctly.
640:480 is a 1:1 A/R for the source. Don't set it to "DVD 720" (if I use that in Fitcd I obtain the same values that you have, with 112 insteed of 88 )
It is very important to set the A/R of both source and destination to reflect what you have and what you want

Prodater64 08-05-2005 01:18 PM

Quote:

Originally Posted by Dialhot
It is very important to set the A/R of both source and destination to reflect what you have and what you want

S**t, you are right. I just unmark itu... and I thought it was enough to point to MS that source is 1:1
Thanks.

Icarus3000 08-05-2005 01:33 PM

Dialhot Wrote:
Quote:

Not if automatic zoom mode is activated on the TV that will switch the screen to "normal 16:9" to "zoomed 4:3" according to what you are looking at.
(Aside: How do I get it to say "Dialhot Wrote" instead of "Quote"???)

Isn't viewing in "zoomed 4:3" mode on a widescreen TV analogous to viewing movies on standard TV's in "Pan&Scan" mode - ie: you cut off some of the original content, in this case from top and bottom? I thought that was passé. :lol:

Prodater64 08-05-2005 02:34 PM

Quote:

Originally Posted by Icarus3000
(Aside: How do I get it to say "Dialhot Wrote" instead of "Quote"???)

Code:


       
Quote:

       
       
               
       
       

                       

                       
                               

                                        Originally Posted by Dialhot
                                       
                               

                               
Text quoted

                       
                       

               



Icarus3000 08-05-2005 03:23 PM

Quote:

Originally Posted by Prodater64
[ quote="Dialhot"]Text quoted[/quote ]

Thanks! :D

Prodater64 08-05-2005 03:30 PM

Quote:

Originally Posted by Icarus3000
Thanks! :D

Your welcome.

Dialhot 08-05-2005 04:14 PM

Quote:

Originally Posted by Icarus3000
Isn't viewing in "zoomed 4:3" mode on a widescreen TV analogous to viewing movies on standard TV's in "Pan&Scan" mode - ie: you cut off some of the original content, in this case from top and bottom? I thought that was passé. :lol:

There are several zoom mode depending on the model and the TV's brand. some crop, others distort a more or less. And all have a special mode call "14:9" that is a mid-way between the distort too much and cropping too much.

GFR 08-08-2005 06:31 AM

My TV (Philips) has a special zoom mode called "superwide" where it zooms a fullscreen 4:3 picture to widescreen 16:9 (almost) without cropping. What it does is it keep the center of the screen undistorted and it gets more stretched as you move towards the sides (L,R).

I think the PowerDVD software has a feature like that, and the reciprocal - it can put 16:9 into 4:3 without cropping (by keeping the middle untouched and squahing the sides).

The theory is that the important part of the picture is the center, as the sides are viewed with your peripherical vision the movement is more important than the actual shape.

In practice, it doesn't work very well :( At least, not always.

I think it would not be very difficult to implement an avs script or function like the above.


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