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-   -   Intermediate resolution between 352x240 and 528x480 ? (http://www.digitalfaq.com/archives/encode/9210-intermediate-resolution-between.html)

jim620 04-19-2004 02:21 PM

Intermediate resolution between 352x240 and 528x480 ?
 
I've been experimenting with different resolutions and was wondering if there was an "official" resolution between 352x240 and 528x480. I've tried 352x480 but I wanted another that will also up the horizontal as well as the vertical. I know that the DVD player will "fit" these resolutions so they will appear normal during playback and just wondering if there are others resolutions that people are using that have worked.

Prodater64 04-19-2004 02:26 PM

480*480 is official SVCD (NTSC) resolution.

jim620 04-19-2004 02:37 PM

Yep, tried it but it doesn't work too well with my player. I was thinking something around 400x360.

Prodater64 04-19-2004 03:24 PM

Quote:

Originally Posted by jim620
Yep, tried it but it doesn't work too well with my player. I was thinking something around 400x360.

As I said mpeg2 480*480 is official SVCD resolution. If you standalone play SVCD it should play this kind of stream.

Do you encode mpeg1 or mpeg2?
You can try all mpeg1 resolution but multiplexing like SVCD and burning like SVCD.

Encoder Master 04-19-2004 03:42 PM

You can also burn your MPEG-1 Files as VCD.

jim620 04-19-2004 04:08 PM

I've been doing KVCD MPEG1 352x240/288 fine for a while now. I then got a hold of a KSVCD at 480x480 and my DVD player played it fine. When I tried to do my own KSVCD my prediction using TOK would show a CQ in either the 50's or 60's at 480x480 and my player would sometimes play it and sometimes not. So what I'm trying to get at is a compromise resolution using MPEG1 where it's greater than 352x240/288 but less than 480x480 so that I can encode it with a higher CQ, either in the 70's or low 80's in order to get a better picture.

Encoder Master 04-19-2004 04:29 PM

But:

480x480 with a CQ of 60 looks better then 352x240 with a CQ of 70. :wink:

Dialhot 04-19-2004 04:47 PM

"Can look", or "should look" if you want but nothing is absolutly sure for all sources.

Prodater64 04-19-2004 06:09 PM

Quote:

Originally Posted by jim620
... So what I'm trying to get at is a compromise resolution using MPEG1 where it's greater than 352x240/288 but less than 480x480 so that I can encode it with a higher CQ, either in the 70's or low 80's in order to get a better picture.

You need to make several samples at:
352*240 mpeg1 and mpeg2
352*480 mpeg1 and mpeg2
480*480 mpeg1 and mpeg2
528*480 mpeg1 and mpeg2
544*480 mpeg1 and mpeg2
704*480 mpeg1 and mpeg2
720*480 mpeg1 and mpeg2

Mux each one (even without sound) to make mpg's. (KVCD and KSVCD)
Burn a CD-RW like VCD with mpeg1 and mpeg2 muxed like VCD.
Test it in your standalone. Write down results.
Erase the CD-RW and burn it again, this time with mpeg1 and mpeg2 but muxed like SVCD.
Test it in your standalone. Write down results.
It is all.

Remember that for 1 CD80 target, low bitrates, it is better mpeg1.
Select better resolution and muxing type that agree with your needs.

Edited: Corrected 2 firsts resolutions like rendalunit points me.

rendalunit 04-21-2004 11:31 PM

Quote:

Originally Posted by Prodater64
You need to make several samples at:
320*240 mpeg1 and mpeg2
320*480 mpeg1 and mpeg2

you mean 352x240 and 352x480 right?

Prodater64 04-21-2004 11:43 PM

Quote:

Originally Posted by rendalunit
Quote:

Originally Posted by Prodater64
You need to make several samples at:
320*240 mpeg1 and mpeg2
320*480 mpeg1 and mpeg2

you mean 352x240 and 352x480 right?

Right, thank you, it was edited now.

jim620 04-22-2004 03:12 PM

If your source is say 512x368 would it be better to "down" the 368 value to 240 or "up" it to 480?

Prodater64 04-22-2004 04:17 PM

Quote:

Originally Posted by jim620
If your source is say 512x368 would it be better to "down" the 368 value to 240 or "up" it to 480?

Most people think and teach that it is better to down this value. I prefer, always relatet to quality obtained, up this value, as I obtain high quality encodes. I think you must to try it for yourself.

Dialhot 04-22-2004 04:54 PM

Quote:

Originally Posted by Prodater64
Most people think and teach that it is better to down this value.

Just to tell that this point (to reduce and never enlarge) is more important on width than on height.
with 368 as original height, I will go to 480. In fact I will go the the value taht gives the less A/R error on Moviestacker.

Prodater64 04-22-2004 05:09 PM

Quote:

Originally Posted by Dialhot
Just to tell that this point (to reduce and never enlarge) is more important on width than on height.
with 368 as original height, I will go to 480. In fact I will go the the value taht gives the less A/R error on Moviestacker.

Yes, of course Dialhot, it mean that you would choice 480*480. Is'n it?

But, can you tell me why, if tv always enlarge width to 704. It is TV or standalone enlarging, better than encoder enlarging?

Dialhot 04-22-2004 07:27 PM

Quote:

Originally Posted by Prodater64
But, can you tell me why, if tv always enlarge width to 704. It is TV or standalone enlarging, better than encoder enlarging?

As you say, TV always enlarge. But it can't enlarge what doesn't exist.

When you reduce a frame before to encode it, you reduce the number of the defaults (the smallest ones disapear). So the TV enlarge a denoised picture.

If you enlarge with the encoder, you enlarge the defaults and the TV will enlarge them a second time.

This process is known in picture processing as "erode/disolve" process.

Prodater64 04-22-2004 08:08 PM

Quote:

Originally Posted by Dialhot
If you enlarge with the encoder, you enlarge the defaults and the TV will enlarge them a second time.

Can we say then, that when reducing resolution, we will obtain a movie with less noise but more blured; and when enlarging resolution, we will obtain a movie with some noise but sharper.
Am I wrong if i think that filters in V4 script permits to reduce noise enough to enlarge resolution safely?
Is the final selection a taste question?

See you Phil. Thanks.

Dialhot 04-23-2004 06:07 PM

Quote:

Originally Posted by Prodater64
Can we say then, that when reducing resolution, we will obtain a movie with less noise but more blured

Right.

Quote:

; and when enlarging resolution, we will obtain a movie with some noise but sharper.
Right again.

Quote:

Am I wrong if i think that filters in V4 script permits to reduce noise enough to enlarge resolution safely?
You are wrong.
Filters in the script are designed to work in "reduce only" way. If you enlarge, you will need to modify (a little) the script.

Quote:

is the final selection a taste question?
As always. But generaly eyes are more sensitive to default than to blur aspect.

Prodater64 04-24-2004 01:28 AM

Quote:

Originally Posted by Dialhot
Filters in the script are designed to work in "reduce only" way. If you enlarge, you will need to modify (a little) the script.

Thank you.

Can you teach me to modify it, in a particular and in a general way?

Dialhot 04-24-2004 06:35 AM

Quote:

Originally Posted by Prodater64
Can you teach me to modify it, in a particular and in a general way?

Whow, that is quite impossible. It a lot a matter of habit and feelings.
You see, is like a chief that does a recipe : he tastes, he think that a little more salt will be better and add a little, then tastes again... but he won't add pepper because he knows for sure that pepper won't be good for that recipe.

Doing a script is quite the same thing :-(

But I can tell you how work : I do everything with the "avisynth" tab of ffdshow. You can add/remove filters and see the result "on the fly" without even stop the play of the video. I use it throught zoomplayer.
This way I can adjts a script very quickly.


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