3 different video formats in a DVD

[Patapin]

Hello,

I wanted to convert a DVD into a mkv file to watch it on my EMTEC TV Box with better subtitles, and it took me long to achieve it, using mkvmerge.
Then, by miracle, success came, I don't really know why, I just know the "how".


[Attachment 52327 - Click to enlarge]
You can see that the width had to be 853. If not, I had black stripes on both sides.

Then I wanted to understand why, and I took a look with MediaInfo at the first video files, and this is becoming strange:

[Attachment 52331 - Click to enlarge]

[Attachment 52332 - Click to enlarge]

[Attachment 52333 - Click to enlarge]

Very surprising, isn't it?
Have you ever seen something like that?

[DB83]

Nothing odd about that.


720*480 is the storage ratio for the dvd - all commercial dvds will be 720*480 (NTSC) or 720*576 (PAL)


But when the dvd is displayed the aspect ratio kicks in and your 720*480 will become 852 or 854*480 (16:9 NTSC). You can not have 853*480 because no display can deal with a number that does not at the very least divide equally by 2.

[Patapin]

Hello DB83,

OK, so it becomes 16:9 NTSC. Thank you, I understand better.
The second image indicates 4:3, and the third 16:9, and corroborate your saying.
Now, what about the last image, showing 2.40:1?
(It's not very important, just for my own knowledge)

And how can I choose the ratio with mkvmerge, without groping around?

[DB83]

2.40 is, again, an aspect ratio. You will see letter-box bars top and bottom.


It is my understanding that transfer a dvd - any dvd - to mkv and aspect ratios are retained. Nothing for you to do. But others with more experience of the mkv container might correct me on that.

[Cornucopia]

That 3rd one, while legit AR for general MPEG2, is NOT legit for DVD. That may have been one of the things causing you trouble.

Also, if you retained the AR flags, you wouldn't have to resize (and resizing loses quality additionally).

Scott

[Patapin]

Thank you for all your enlightments, they are precious.
I'll try to remember all this.