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  1. Member
    Join Date: Jun 2006
    Location: United States
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    Hello,

    I tried using the search function and found nothing on this case. And I have also done LOADS of research and haven't been able to figure this out.

    I have a mini-DV camcorder that records (natively) in 16:9, meaning it's 720x480 NTSC. It displays correctly in Windows Media Player and on television on a DVD when I export the captured video as Microsoft DV AVI (and flagged it as 16:9). I've used both Adobe Premiere and VirtualDub to do this. However, when I try to compress the AVI using the XviD codec, it loses its 16:9 tag and then displays squished in any media player. I was wondering if there is ANY way to compress a DV AVI using anything like DivX or XviD without losing its 16:9 flag? I've tried telling it that the movie is 16:9, but no luck. Is 720x480 NTSC just plain terrible and not very flexible? Or am I really missing a lot of knowledge?

    I should have known that buying a camcorder that records natively in 16:9 would of been a bad idea. Trust me, the CCD IS 16:9 native, I've even tested this by switching to 4:3 and seeing if I gain more on the top and bottom, but instead I lose information on both sides.

    If anyone can help me, I would be so thankful.

    thanks.
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  2. Member
    Join Date: Jun 2004
    Location: Victoria, Australia
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    Not sure how you're "tagging" an AVI file as 16:9 ... MPG files have an internal DAR flag to tell the player to "stretch" the 720x480 (which isn't a 16:9 ratio, you'll notice) at playback. AVI's always assume a square aspect ratio (correct me here, guys), and you'll need to manually re-size the image to a "real" 16:9 ratio during the encode. Note sure with NTSC sizes, but I know a PAL 720x576 MPG becomes 1024x576 at playback.

    Trev
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  3. Member
    Join Date: Jun 2006
    Location: United States
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    Thanks for the reply.

    When I capture video in either VirtualDub or Adobe Premiere, they both automatically save as an AVI file. I have no idea what it's encoded in, except that in Adobe Premiere it simply calls it "Microsoft DV AVI". These AVI's are being squished down vertically by any media player to keep the 16:9 ratio. If you want, I can try to upload a 5 second clip from one of these (they weigh a ton in size, so it's going to have to be really short so that you can download it).

    So basically what I'm saying (as for NTSC goes) is that these AVIs are automatically being squished down by media players to be like 720x405.
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  4. aBigMeanie aedipuss's Avatar
    Join Date: Oct 2005
    Location: 666th portal
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    720x480 is 4:3 not 16x9. what you have are black bars recorded top and bottom. all the settings for your conversions should be 4:3 to keep the aspect ratio correct. dv-avi only comes in the 720x480 flavor for ntsc. you might try transferring with windv to a file from the cam so you can see the original dv-avi like it is on the tape.
    --
    "a lot of people are better dead" - prisoner KSC2-303
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  5. Use Xvid's aspect ratio setting:

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  6. Member
    Join Date: Jun 2006
    Location: United States
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    Originally Posted by aedipuss
    720x480 is 4:3 not 16x9. what you have are black bars recorded top and bottom. all the settings for your conversions should be 4:3 to keep the aspect ratio correct. dv-avi only comes in the 720x480 flavor for ntsc. you might try transferring with windv to a file from the cam so you can see the original dv-avi like it is on the tape.
    My video camera DOES record true 16:9. I'm dead serious. It is NOT adding black bars on the top and bottom Here is complete proof to show you:

    http://icedog.apocmedia.com/16by9.png - Direct screenshot from 16:9 footage.

    http://icedog.apocmedia.com/4by3.png - Direct screenshot from 4:3 footage.

    Both were never edited. They're both directly from my camcorder. Can you see that there is resolution being lost in the 4:3 screenshot?

    Originally Posted by jagabo
    Use Xvid's aspect ratio setting:

    Image Here
    I've already tried that, but for some reason I missed that message below it. That definitely explains it, but VirtualDub doesn't export as mpeg-2. Is there a mod for it that gives it the ability to do that? Or do you suggest another program?

    Thanks.
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  7. When you play on a computer there are two main ways a player can maintain the aspect ratio. Shrink the height or stretch the width. I'm not sure about this but the default behaviour may be a matter of the DV codec installed.

    Try using Media Player Classic for playback on the PC. I has the option to use the aspect ratio setting when playing files, including Xvid.

    Just about any MPEG encoder will let you create 720x480 MPEG files with 16:9 PAR. Just make sure it identifies the source as 16:9 and that you specify the output should be 16:9. It works with TMPGEnc Plus.
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  8. Member 1st class
    Join Date: Aug 2004
    Location: Charlotte
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    Originally Posted by Flyingsheep
    Thanks for the reply.

    When I capture video in either VirtualDub or Adobe Premiere, they both automatically save as an AVI file. I have no idea what it's encoded in, except that in Adobe Premiere it simply calls it "Microsoft DV AVI". These AVI's are being squished down vertically by any media player to keep the 16:9 ratio. If you want, I can try to upload a 5 second clip from one of these (they weigh a ton in size, so it's going to have to be really short so that you can download it).

    So basically what I'm saying (as for NTSC goes) is that these AVIs are automatically being squished down by media players to be like 720x405.
    I can sympathize with your frustration as I am also trying to figure out the nuances of working with true 16:9 camcorder captures. There are a couple things I have learned that are helpful; First, windv is a truly excellent capture program for getting your video from the camera to the hard drive with good scene selection (and it is free). During the capture, the preview window looks like it is squishing the video, but it really isn't. Once you have the capture on your hard drive as an uncompressed .avi, Adobe Premiere should have no problem importing it. Just make sure that you start your Premier project as a 16:9 project. An odd thing I noticed was that when I opened the uncompressed .avi in Media Player Classic, it looked squished as you are experiencing with Windows Media Player. Once I resized the player window, it went to the proper proportion.
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  9. Member Cornucopia's Avatar
    Join Date: Oct 2001
    Location: Deep in the Heart of Texas
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    Note: there are fields in an AVI header/file which, in combination with the resolution fields, could be used to determine DAR. Except they NEVER are used that way.

    So how does an AVI know DAR for DivX/Xvid and DV, but not most everything else?

    The Video stream incorporates it. DivX/Xvid, etc are MPEG4, which we already know has a DAR field, just like MPEG2. DV also has a DAR field, embedded in the user data section of the stream, along with timecode data, etc.

    It should be possible to manipulate just that, and nothing else, retaining original quality. It's possible that DVDate or some other DV file adjusters may also inadvertantly have that feature too. If not, there might be a way to hexedit it in if you could figure out the spots it's supposed to reside.

    ....You know, I think this topic was discussed before--do a search...

    Scott
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  10. Member
    Join Date: Apr 2002
    Location: Oskeeweewee Ontario
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    jagabo's correct,
    I'm not certain about XVID encoding nuances, but since your pixel aspect ratio is 16:9, i would suggest that you check this within the encoding parameters also...

    Does XVID support interlacing??
    If not, it would be a shame to see you have to deinterlace that fine detail....
    Nice pics...
    I've got a Panasonic GS-400, and totally love the 1.2 pixel aspect ratio...
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  11. Originally Posted by pijetro
    Does XVID support interlacing??
    Yes, but most players don't really know what to do with it.
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  12. Member
    Join Date: Jun 2006
    Location: United States
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    Thanks everyone for replying, but unfortunately I am still stuck. I tried TMPGEnc Plus and successfully encoded an avi to mpg, but instead of squishing it down it interpolated the resolution so that it would fit 16:9. I don't want to interpolate my videos, they lose so much detail that way. I tried putting it back to a 4:3 ratio and setting the output resolution to 640x360. When I tried playing that it would display correctly of course but it would add useless black around the video, making it weigh a lot more in size.

    pijetro, I have a Panasonic GS-39. I am curious as to which methods you use to compress your footage (mpg or AVI, I don't care) while still properly keeping the 16:9 ratio.
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  13. Member
    Join Date: Jun 2004
    Location: Victoria, Australia
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    Originally Posted by Flyingsheep
    ...My video camera DOES record true 16:9. I'm dead serious. It is NOT adding black bars on the top and bottom Here is complete proof to show you:

    http://icedog.apocmedia.com/16by9.png - Direct screenshot from 16:9 footage.

    http://icedog.apocmedia.com/4by3.png - Direct screenshot from 4:3 footage.

    Both were never edited. They're both directly from my camcorder. Can you see that there is resolution being lost in the 4:3 screenshot?...
    Hmmm...neither of those images is 720x480 NTSC??

    Load the AVI into VirtualDUB. Is the OUTPUT preview ratio correct? If not, load the RESIZE video filter and stretch to the correct size. Compare the INPUT and OUTPUT preview windows to get the result you require.

    Now it's just a matter of setting the Video Compression settings (without doing any further resizing in the encoder) and saving out a new AVI with the new size and different compression from the original!

    Trev
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  14. Member
    Join Date: Jun 2006
    Location: United States
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    Both of the images are 720x480 NTSC.

    I actually tried that method a month ago and I would always get this weird error when I tried to save the AVI. I figured it was just something you couldn't do in NTSC.
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  15. Member
    Join Date: Oct 2005
    Location: United Kingdom
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    erm .... dropping these into a photo editor says they are 640x480 and 640x360 therefore not NTSC resolution
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  16. Member
    Join Date: Jun 2006
    Location: United States
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    They were screenshots from real 720x480 footage. The media player resized them to be their proper ratios. If you still don't believe me for whatever reason, I can upload the actual video clips themselves so that you can open an editor program and see that it IS 720x480.
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  17. You don't have to. Anyone that knows anything about the subject already believes you. aedipuss earlier and skinm and TJohns just above, you can ignore.

    Unless you play your XviDs with the 16:9 flag in a player that respects it, of course you'll only get 720x480 playback with bad AR. And if you intend ever to play them in a standalone DVD/MPEG-4 player, most don't read the flag. I think your best bet is to resize to 640x352 or something like that.
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  18. Member
    Join Date: Oct 2005
    Location: United Kingdom
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    I am sorry for being completely stupid, but the poster did specify "They're both directly from my camcorder". The poster has now stated that it is his media player that has resized it to 640x480. I can only work with the facts!
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  19. Member
    Join Date: Jun 2006
    Location: United States
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    oh, sorry. I thought I did. I guess I'm the stupid one.

    Well, I can work around converting to mpg to keep the 16:9 ratio. If I resize it to be 640x360 then it doesn't really lose detail at all and still looks nice (apparently mpg likes to interpolate). Thanks everyone for the help, I'm glad I have some method that actually works, and I have a better understanding of this now.
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