which muxer handles NTSC 704x480 2.21:1AR 29.97fps mpeg2

[halsboss]

Hello, I'm wanting to create a DVD-compatible mpeg2 program stream (ie a .mpg file) from mpeg2 compatible .mpv/.ac3 elementary streams eg the test clip comes from HCenc... NTSC 704x480 2.21:1AR 29.97fps.

Looked at a couple of muxers and it seemed as if they handle 4:3 and 16:9 only ... can you please recommend a muxer that works ? Either gui or commandline is fine. Preferably one which handles PAL 4:3,16:9 as well.

[guns1inger]

mpeg allows for a DAR of 2.21 : 1. DVD does not. Hence the muxers only handle 4:3 and 16:9.

Time to resize and re-encode

[manono]

Or mux into an MPEG using Imago MPEG Muxer, or some such.

[halsboss]

Thanks guns1inger and manono. Tried Imago MPEG Muxer and that worked however the DVD authoring programs only allowed 16:9 and 4:3.

The underlying challenge was to make a clip which was 2.35:1 onto a DVD, so I used HCenc to resize to 704x480 with aspect ratio 2.21:1 (HCenc v023 didn't allow 2.35:1) to see how that went. OK, however see above re actual authoring.

I gather some commercial DVDs do display, somehow, in 2.35:1 as I think it says so on some labels - so I wonder how I can go about it ?

Is it a matter of resizing to a bit less that 480 and adding some black to make it back up to 480 and then specifying 16:9 (if so, what's the size of the black bars) ? Is that how the commercial DVDs do it or is there some other way.

[guns1inger]

You have to resize and encode for 16:9. Your resizing process will have to add whatever black bars are required for maintain the correct aspect ratio. DVD video from 2.35:1 source has black bars added and is encoded as 16:9. That is your only choice.

I suggest you have a look at either FitCD to have a look at the avisynth script it creates, or AVStoDVD, which will do the entire process for you.

[halsboss]

OK thanks. Is that what the studios do too (the black bars thing) ?

[manono]

OK thanks. Is that what the studios do too (the black bars thing) ?

Yes, there's no other way. Just play a 2.35:1 16:9 movie on DVD sometime. There are a ton of them available, and if you have any kind of a DVD collection at all you'll have some. If playing on a widescreen TV set, the black bars you see are part of the encoded image. If playing on a regular old "square" TV set, some of the black will be part of the encoded picture and some will have been added by the player.

[jagabo]

Just to put it all in one place: MPEG only has four aspect ratio settings: square pixel, 4:3, 16:9, and 2.21:1. Of those four aspect ratios DVD only supports two: 4:3 and 16:9. Any other source aspect ratio must have letterbox or pillarbox bars added to fill out a 4:3 or 16:9 frame.

[halsboss]

OK, based on http://www.pcdoctor-guide.com/wordpress/?page_id=1634 it appears that the right thing to do in this case is under 4. in the table below, ie resize to 704x363 (yes I know, 720, but I prefer 704) and then add black bars to size 59 to the top and 58 to the bottom, then encode with HCenc as 16:9 ... ?

resizeWidth = 704
resizeHeight = 363
lanczos4resize(resizeWidth,resizeHeight).LimitedSharpenFaster(smode=4,strength=100)
BBtop=59
BBbot=58
AddBorders(0,BBtop,0,BBbot,$000000)

1.A.R.	4x3 PAL	 	BB Top	BB Bot
1.33:1	720 x 576 	0	0
1.66:1	720 x 461 	58	57
1.78:1	720 x 430 	73	73
1.85:1	720 x 414 	81	81
2.35:1	720 x 326 	125	125

2.A.R.	16x9 PAL	BB Top	BB Bot
1.33:1	538 x 576	0	0
1.66:1	671 x 576 	0	0
1.78:1	720 x 576 	0	0
1.85:1	720 x 554 	11	11
2.35:1	720 x 436 	70	70

3.A.R.	4x3 NTSC	BB Top	BB Bot
1.33:1	720 x 480 	0	0
1.66:1	720 x 384 	48	48
1.78:1	720 x 358 	61	61
1.85:1	720 x 345 	68	67
2.35:1	720 x 271	105	104

4.A.R.	16x9 NTSC	BB Top	BB Bot
1.33:1	538 x 480	0	0
1.66:1	671 x 480	0	0
1.78:1	720 x 480	0	0
1.85:1	720 x 461	10	9
2.35:1	720 x 363	59	58

[jagabo]

resize to 704x363 (yes I know, 720, but I prefer 704) and then add black bars to size 59 to the top and 58 to the bottom, then encode with HCenc as 16:9 ... ?

Yes, except:

MPEG encoding will work better with mod8 or mod16 sizes. Resizing to 704x360 or 704x368 will compress better than 704x363. And keeping the video aligned on a mod8 or mod16 boundary will work better:

704x360 with 56 lines of letterbox on the top and 64 on the bottom (or vice versa).

Or if you insist on keeping the 363 lines:

704x363 with 56 lines of letterbox on the top and 61 on the bottom.

Also, avoid using odd (as in even vs odd) values on the top or left when adding borders. Odd values will cause additional blurring of the chroma channels.

[halsboss]

Oh joy, really good info there jagabo ! Thanks, I'll see if I can jiggle the table accordingly on the principle of "close enough size, you'll never notice it".

[guns1inger]

Again, I strongly suggest FitCD, even if you only use it so you can see the calculations it produces.

[manono]

Yep, forget the tables and use FitCD. Most movies aren't really 2.35:1 anyway. That's just used as a sort of generic ratio. Most are more like 2.39:1 or even a bit wider after being prepared for DVD. If you're going to be picky about the 704/720 thing (which FitCD can be made to honor), you'll certainly want to make sure the movie AR is correct as well.