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  1. I apologize if there was another thread about the same thing already posted. I didn't have time to check thoroughly.

    So:
    Are there any programs that could re-stretch properly a video file (which I believe has been crushed from 2.35:1 to about 1.78:1, or rather 1.73:1)?

    I don't want to insert black bars on the sides, of course, but rather to give the figures in the movie their correct proportions.

    Thanks.

    P.S. Ideally, I'd like to do this with a minimum of fuss. Does the old TMPGEnc Xpress do this, maybe? That's a very intuitive program. I probably couldn't figure out AVISynth quickly, on the other hand...
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  2. You can remux the video with the correct aspect ratio flags. That will only take a few seconds and there will be no loss of quality. Use MMG, Yamb, etc. Only players that support aspect ratio flagging at the container level will work though.
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  3. If it was me, I'd be inclined to re-encode it while resizing to the correct square pixel aspect ratio. That way it'll always display correctly. If you use the x264 encoder and a high enough quality setting there should be no noticeable, or negligible, quality loss. Any encoder GUI which allows you to freely resize should do the trick. I don't use it myself, but I'm pretty sure Vidcoder does and it's fairly easy to use.

    For a minimum or a maximum of fuss, depending on how good you are with commandlines:
    New tool to change SAR in H264 bitstream
    Once it's done it's thing, if need be you could use MKVMergeGUI or My MP4Box GUI to remux and set the container aspect ratio to match the stream aspect ratio again.
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  4. Other tools I've seen only allow you to change the SAR flags if the h.264 stream has SAR flags to begin with. They can't add SAR flags to a video that doesn't have them.
    Last edited by jagabo; 31st Mar 2014 at 06:17.
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  5. Could you be a little more specific for a dude who doesn't know as much as you, guys, please?

    If I start the respective program, and open/select/browse(to) the file I want remuxed, there will be an option there saying 'remux'?
    And then I can fiddle with the settings?
    (Or is it not as simple as I imagine?)

    Just please a little more explicit, for me. Some of the terms you used went straight over my head. Thanks very much, again.
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  6. Oh, and I want to reencode (re-stretch) as an AVI, so I can play it on my DVD DivX player connected to the TV.

    If the result would only play only on some (computer media) players, so not guaranteed to play, then it might not be good for me, right?
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  7. There's two ways the aspect ratio can be (and usually is) stored. It's written to the video stream itself and it can be saved as information in the video container (MKV, MP4, AVI etc). Normally they're the same.

    If you use a program such as MKVMergeGUI or My MP4 Box GUI you can set an aspect ratio when remuxing (yes there's a remux button as that's what they do). It will change the container aspect ratio.

    The issue is then, if the two aspect ratios are different, which one the player will obey. I think generally they'll use the container aspect ratio first. Assuming the player actually supports aspect ratios in MKV, MP4, AVI files. Not all do and they'll display the video as though it consists of square pixels regardless of any aspect ratio.

    Aspect ratios in AVIs are generally not supported by standalone players at all. I don't think the AVI spec allows for container aspect ratios. Is the type of video in question a secret?

    If you want to convert it to an AVI which will display correctly, the most reliable method would probably be to resize it to whichever dimensions give you the correct aspect ratio and encode it that way (using square pixels). Without knowing the type of video you have it's hard to recommend a program which will definitely do the job. Not all programs will open all file types and support for converting to Xvid/Divx/AVI is becoming less common. You'll also need a program which lets you resize freely. Many programs will try to discourage you from stretching the picture while resizing as normally that's not what you'd want to happen.

    I'd use MeGUI myself but it has a bit of a learning curve. Someone else may be able to suggest something easier. Maybe XviD4PSP?
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  8. Originally Posted by newsgroup guy View Post
    Oh, and I want to reencode (re-stretch) as an AVI, so I can play it on my DVD DivX player connected to the TV.
    If your video is already Divx or Xvid AVI use Mpeg4Modifier to remux with whatever Display Aspect Ratio (the final shape of the picture) or Pixel Aspect Ratio (the shape of individual pixels):

    Name:  mpeg4mod.png
Views: 153
Size:  510.8 KB

    Browse to the video, set the Display AR to 16:9, Save.
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  9. There's no secret regarding what kind of file I'm trying to convert. I believe you both kind of inquired. So here it is:

    Originally, I got a MKV file. It seems like the original video was 2.35:1 or 2.40:1. The aspect ratio Handbrake gives me, for the MKV, is 1.73:1. I divided the length by the height, to get that number.

    But I can't import and edit MKVs. I only have Vegas and TMPGEnc Authoring Works. (Windows 7.) I used to have Xpress, but now I'm using Authoring Works. In any case, they can't even open MKVs.
    Oh, and, of course, I also have the free program Handbrake. Would that stretch the file properly, by the way? (It's free, so I'm skeptical. But, on the other hand, it's a wonderful converter - MKV to MP4 and DVD to MP4 work great, at the very least.)

    The way I'm doing the conversion to AVI, therefore, is in two steps: MKV->MP4 (Handbrake), and then MP4->DIVX (Authoring Works). It works well, but Authoring Works doesn't stretch but adds black sidebars.

    So I'm working with MP4, basically, unless you know of a program that converts and stretches MKV->AVI in one single move.

    Jagabo, I'm reading about MPEG4-modifier right now. It should open MP4s, no? After all, the name...


    And yeah, why not, I'll try Handbrake right now, since I already have it installed, and then post back. Afterwards, I'll try the other suggestions. Thank you again, guys.


    P.S. I tried MeGUI a couple of times a while back, Hello_hello, but I couldn't get it to output AVI, even though it had AVI selected. Even when editing an AVI... It kept outputting MKVs, no matter what the setting. And I can't use MKVs.
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  10. Originally Posted by newsgroup guy View Post
    Jagabo, I'm reading about MPEG4-modifier right now. It should open MP4s, no? After all, the name...
    No. Divx is an MPEG 4 Part 2 codec, hence the MPEG4 in the name. That has nothing to do with the MP4 container.

    What are the codecs used in your MKV file? The video is most likely h.264 (AVC) so you'll have to convert to Divx as well as changing the container. That requires a complete re-encode. You could use VirtualDub to resize and reencode. You'll need to download and install the ffmpeg source plugin for VirtualDub.
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  11. Hi.

    I don't know what codec was used, but you know what?

    Handbrake did the job!

    I'm suprised it was so easy, really I am.

    But I just imported the file, and under 'Video' selected "Custom", then ticked off "Keep Aspect Ratio", and modified the height to be 308 (instead of 416 -- 720x416 modified to 720x308). Clicked 'Start' afterwards and it took about 15 minutes.

    Nice!

    It all looks proportional now.
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  12. One more thing to mention, for other people interested.

    Handbrake will stretch to less than the already-encoded proportions (e.g. from 656 pixels length to 640, or from 366 pixels height to 360, or from 650x370 to 320x240) but not to more. E.g. it is not allowed to alter from 640x360 to 720x405.

    May be useful to know beforehand.

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  13. That might be why nobody suggested Handbrake. Well that and the fact you said you wanted the output to be AVI. If the ultimate aim is to play the video using an AVI capable DVD player, chances are the maximum width you can resize to will be 720 anyway.

    Vidcoder is an alternative Handbrake GUI. I'm pretty sure it'll let you resize "up" exactly the same way Handbrake doesn't.
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