TmpgEnc resolution/aspect ratio prob

[tommyruff]

Hi, I'm confused, can anyone help me out with this problem. I have a source avi that I wish to eventually convert to DVD format, but I can't seem to get the correct final aspect ratio. Gspot tells me my source avi is NTSC 23.976 fps with a resolution of 576x304 . I don't really care if its converted to NTSC or PAL although I would prefer PAL . I've tried heaps of guides but the final aspect ratio is not correct. The source resolution of 576x304 seems very odd, are there corrections i need to make?

I should say I want the final picture 16:9 to view on a 4:3 TV

Regards Tommyruff

[monzie]

OK if its going to be a PAL the vertical needs to be 432 (to make 1:1.777=16:9) so add 72 borders top and bottom (A SLIGHT STRECTH)......BUT if your a real stickler use 400 vertical (1 : 1.92) and 88 T & B... or.... 416 with 80 T&B (1 : 1:85) which are both closer your originals AR (1.895).


For NTSC use 336 vertical with 72 borders.

HTH

[tommyruff]

Thanks for the response Monzie
....but you have totally confused me with your arrived figures.
For a start,
1. Should I use Project Wizard and select PAL 16:9
2. what do i put as the source aspect ratio ?
3. In the Video Arrange Method section...what do I leave the horizontal and vertical pixel size as?

I see 16:9 = 1.777:1
I see 576x304 = 1.89:1

can you explain it to this dumb newbie please

Regards Tommyruff

[monzie]

Those figures I gave your where for making a 16:9 film with an final DAR of 4:3 (letterboxed to 16:9) which is correct for a 4:3 TV (which you asked for in your first post).

You have to understand that DVD's can be either 4:3 DAR or 16:9 DAR this governs how the video footage will be DISPLAYED on the TV..forget for now a DVD's resolution (720X 480 NTSC or 720 x576 PAL....these are NOT the playback resolutions!).

All TV's work by scan lines, scan lines are the number of horizontal lines (or in pc language its VERTICAL resolution).

So a PAL DVD (and TV) have a VERTICAL res of 576.

So for a 4:3DAR DVD take the VERTICAL (576) divide by 3 and multiply by 4:

576/3 =192........192 X 4 =768

Therefore a PAL DVD (encoded at 4:3DAR) when PLAYED BACK on a normal 4:3 TV will have a resolution of 768 X 576 (and not 720 X 576 which you may think it is being a PAL DVD's resolution.

If you have ws telly or a 4:3 telly with a 16:9 mode you can use the 16:9DAR for encoding.

576/9 = 64..........64 X 16 =1024

So the TV playback resolution for an encoded DVD using 16:9 DAR is 1024 x 576.

So if you want to use 16:9DAR for encoding your vertical will need to be 544 with borders of 16 T & B...remember to go to the nearest multiple of 16 (the real figure is 1024/1.859 =550.8) or just use 550 (as its not strictly necessary to go to the nearest 16).

If you have a good software DVD player take a snapshot of the footage and then open it up in a photo editor and check its size...you will then see what i mean.......DAR's are a form of compression.

For NTSC DVD's

480/3 =160...........160 X 4 =640 so playback on a TV is 640 X 480 when 4:3......so in your case 640/1.895 =336 (from 337.7)

For 16:9DAR on NTSC the playback is 852 X 480...in this case 852/1.895 = 448 (from 449.6)

NOTES
Encode the DAR to suit your TV....AND
....use 16:9DAR when possible as you get a higher vertical resolution (smaller borders)....presuming your telly can handle DVD's encoded at 16:9DAR
The actual DVD/TV PIXELS are stretched to take up the amount of space of the CALCULATED horizontal resolution when using 16.9DAR.....there are no 'real' extra pixels.... so just understand the calcs and remember to only adjust the VERTICAL resolutions.

Its how i understand it all anyway............

[US Guy]

My humble opinion is to try and play with the settings to find out what is good for your eyes. It's like learning how to ride a bicycle. Most people stumble a few times before they can balance the ride. Unless you are totally useless, then please just ask those Damn Unique Mostly Boring (D.U.M.B.) questions.