Help on aspect ratios...

[nightsky]

Well I tried searching for this and I ended up getting tired of browsing through topics and I didn't get to find much help on the topic so I guess I'd try posting.

I was wondering if anyone knows how to store aspect ratio information into a video file (particularly encoded with XviD or x264). I tried ripping a NTSC DVD so the resolution would be 720x480. I already considered resizing the output file so that the resolution would fit the 16:9 aspect ratio but what I want is to store the output using the same resolution to keep the vertical pixels.

The problem I found with that is that the image turns out to be stretched. I am aware that players and codecs can override this aspect ratio to make it fit properly. What I would like to know is if there is a way to store the aspect ratio into the file so that most players would resize the video by default instead of having the user do it manually? Any suggestions? Thanks!

P.S. I tried changing PAR and DAR settings on XviD and they didn't help. I used MPClassic and WMP to test the video.

[jel]

hi nightsky and welcome to the fourm!

hopefully this thread offers some insight into your query.
rip anamorphic or not? (http://forum.doom9.org/showthread.php?t=106576)

cheers
j

[nightsky]

Thanks for the reply! Well, I already tried using MPEG-4 Modifier to manipulate the default aspect ratio setting of my encodes but they still look vertically stretched when I play them. Of course I could just change the default decoding AR on my end but other users will have to do that manually too. What I was hoping for is more of an encoding solution rather than a decoding solution.

I think I've seen some encodes around with 720x480 resolutions which displays properly. But then I can't seem to rip the DVD that way. If I rip it as anamorphic the resolution changes and if I rip it with square pixels, the image distorts.

[jel]

but other users will have to do that manually too.what other users? why would it matter why anyone but yourself knows how to correctly playback these encodes?

just a friendly warning but you are dancing very close to a rule 6 violation...

[nightsky]

Well the DVD I'm trying to rip is a playable of a video we shot a few years back (high school project). Apparently I lost the original raws from the tapes so I decided to use the DVD backups we made to re-edit it with my friends for fun. Since this is going to be distributed via the internet to old friends, I find it quite inconvenient to instruct each of them how to work the aspect ratio more so since a lot of them don't even use MPEG-4 videos frequently in the first place.

Well anyway, I tried changing DAR and PAR in the XviD settings and putting it in an MKV container set to the 16:9 aspect ratio but my players still wont play it right. Any more help would be appreciated. Thanks!

[manono]

Suggestions? Don't reencode it to 720x480. Most likely your friends will be using WMP to play it, and you can forget about them ever seeing it with the correct AR. In addition, they may not even have XviD or DivX installed. So, reencode to 640x352 or whatever (1:1), and make the XviD codec available for them to play it. Most players don't read the DAR flag. And forget MKV. Just more stuff they'll have to install, ffdshow, I guess.

If you want them to be sure and be able to play it without having to install anything, then MPEG-1 is your safest choice.

[nightsky]

Well then I guess I might as well resize it during encoding. Thanks!

Oh, and out of curiosity, is it possible to achieve the normal aspect ratio at DVD resolution that I wanted using MKV without having to install or change decoder settings?

[manono]

Hi-

I don't know anything about MKV, so someone that understands the question will have to answer that one. If you don't get an answer here, you might try the New and alternative a/v containers Forum.

If you're asking what is the DVD resolution after having been resized, or without altering the height, then the answer is 854x480. 16/9 x 480 = 853.33. That's only Mod2, so 848x480 might be better. Maybe there are some black bars to crop away. I don't know. At that resolution, you'll need a larger file size for the same quality when compared to the 640x352 I suggested before. And you may have friends with computers not powerful enough to play it without stuttering. Don't know for sure, as I haven't messed with higher resolutions.