720X480 VS 640X480 !

Myouh · Post by **Myouh** » Fri Feb 23, 2007 3:38 pm

what video resolution looks better on a computer, 720X480 or 640X480 ?

BasharOfTheAges · Post by **BasharOfTheAges** » Fri Feb 23, 2007 4:57 pm

That depends entirely on what the PAR and resolution of your source is.

Niotex · Post by **Niotex** » Fri Feb 23, 2007 5:00 pm

1920x1080 looks the best

Corran · Post by **Corran** » Fri Feb 23, 2007 5:48 pm

Myouh wrote:what video resolution looks better on a computer, 720X480 or 640X480 ?

For computer viewing:
using DVD footage with a 4:3 aspect ratio: 640x480
using DVD footage with a 16:9 aspect ratio: 640x352 (360 ideally but that isn't divisible by 16)

Willen · Post by **Willen** » Sat Feb 24, 2007 5:36 am

Corran wrote:
Myouh wrote:what video resolution looks better on a computer, 720X480 or 640X480 ?
For computer viewing:
using DVD footage with a 4:3 aspect ratio: 640x480
using DVD footage with a 16:9 aspect ratio: 640x352 (360 ideally but that isn't divisible by 16)

x100

Other options for 16:9 footage:

848x480
768x432 <---- exactly 16:9!
720x400
704x400

Zero1 · Post by **Zero1** » Sun Feb 25, 2007 5:01 am

What you do is resize to 640x360, then crop to 352; then it doesn't matter that 640x352 is not true 16:9 because you already rescaled your footage to the correct aspect ratio, just you cropped a little from the top and bottom.

The framesize/aspect ratio is pretty irrelevant, providing your footage is the correct aspect ratio.

Another thing would be to use a combination of codec/container that supports aspect ratio flags. MPEG-2 in MPG is most well known but a little big. MPEG-4 ASP (DivX/XviD) also supports aspect ratios, but what with AVI being outdated, whether they take effect or not is hit and miss, and dependant on the end users playback software (since AVI doesn't officially deal with aspect ratios, but some decoders may pick up the AR information from the video stream and act accordingly). If you use the command line XviD encoder and store it in MP4, that will work fine if you want XviD with aspect ratio. Another combination is H.264 in MP4 or even MKV. I didn't mention ASP in MKV, because AFAIK there are still bugs in it's native ASP support, but MP4 is fine with everything.

Doing the aspect ratio flag means you can keep it 720x480 and tell it to resize to 4:3, 16:9 or whatever on playback. This means that you don't waste bitrate encoding an over large image, and you don't get any nasty resizing artifacts such as ringing (AFAIK Windows tends to use a bilinear resizer).

YouTube · Post by **Kionon** » Mon Mar 05, 2007 6:01 pm

I wouldn't normally necropost, but this is relevant:

Is 768x432 divisible by 16 and therefore can be placed in h264 and MP4?

Kitsuner · Post by **Kitsuner** » Mon Mar 05, 2007 6:04 pm

Kionon wrote:I wouldn't normally necropost, but this is relevant:

Is 768x432 divisible by 16 and therefore can be placed in h264 and MP4?

Someone doesn't know how to work a calculator...

YouTube · Post by **Kionon** » Mon Mar 05, 2007 6:07 pm

Kitsuner wrote:
Kionon wrote:I wouldn't normally necropost, but this is relevant:

Is 768x432 divisible by 16 and therefore can be placed in h264 and MP4?
Someone doesn't know how to work a calculator...

Nope. Numbers confuse me.

I'm a writer remember? I can't even add.

CrackTheSky · Post by **CrackTheSky** » Mon Mar 05, 2007 6:38 pm

Kionon wrote:I wouldn't normally necropost, but this is relevant:

Is 768x432 divisible by 16 and therefore can be placed in h264 and MP4?

According to my calculator...yes.