VideoHelp Forum
+ Reply to Thread
Results 1 to 12 of 12
Thread
  1. I have avi's from Premiere and After Effects, directly opened to CCE and TMPG, encoded as NTSC 4:3 DVD compliant streams.

    I just noticed that the size of the encoded video is 720 X 540, and is a little stretched vertically.

    Can someone give me a not too technical explantion of why the output is not 720 x 480?
    Quote Quote  
  2. Member yoda313's Avatar
    Join Date: Jun 2004
    Location: The Animus
    Search Comp PM
    Hello,

    Originally Posted by videohelp - what is dvd
    PAL

    Video:
    Up to 9.8 Mbps* (9800 kbps*) MPEG2 video
    Up to 1.856 Mbps (1856 kbps) MPEG1 video
    720 x 576 pixels MPEG2 (Called Full-D1)
    704 x 576 pixels MPEG2
    352 x 576 pixels MPEG2 (Called Half-D1, same as the CVD Standard)
    352 x 288 pixels MPEG2
    352 x 288 pixels MPEG1 (Same as the VCD Standard)
    25 fps*
    16:9 Anamorphic (only supported by 720x576)
    That isn't ANY DVD standard!!

    NTSC is 720x480 or 352x480.
    Pal is 720x576 or 352x576.

    How did you come up with that resolution???? It shouldn't be outputted by ANY software.....



    Sorry never came across that.....

    Kevin
    Donatello - The Shredder? Michelangelo - Maybe all that hardware is for making coleslaw?
    Quote Quote  
  3. I'm a Super Moderator johns0's Avatar
    Join Date: Jun 2002
    Location: canada
    Search Comp PM
    You have to set the proper resolution size in tmpgenc and cce before you start encoding,if you input the avi without selecting a template or setting the size or script command then it will encode what it sees.
    I think,therefore i am a hamster.
    Quote Quote  
  4. OK, I did the arithmetic. 720 x 540 is exactly 4:3 aspect. 720 x 480 is not 4:3. Now I am on the verge of understanding square pixels vs. rectangular pixels. I think the 540 vertical is to make square pixel display 4:3 legal. The same clip will measure 480 on rectangular pixel displays.

    I checked my clip using Windows media player properties = 720 x 540. I don't know how to check the same properties on a TV set, so I hypothesize this is the case.

    The problem is for square pixel displays, the clip is still slightly distorted vertically. Conversely, if I were to output clips at 720x 540, the image would be stretched horizontally on rectangular pixel displays?
    Quote Quote  
  5. Hi-

    The same clip will measure 480 on rectangular pixel displays.

    Hardly. All NTSC DVDs are 720x480=1.5:1. If encoded 4:3, they should look slightly squashed before resizing. If encoded 16:9, they should look vertically stretched before the resizing. That's how the information is stored on the DVD, but that's before being resized. If you look at the unresized 720x480 DVD image, like in DVD2AVI, for example, it's distorted. It's supposed to be distorted, anyway. If it's encoded as 4:3, if done right, it gets resized to 640x480 (480x4/3=640) and no longer looks distorted. If it's encoded at 16:9, then it gets resized to 854x480 by your player (480x16/9=853.333) and no longer looks distorted.

    I don't know how you wound up with a distorted looking 720x540 image, but you obviously screwed up somewhere along the line. I believe that 720x540 (same ratio as 640x480) is the resized image, and it's really still 720x480. There are a number of ways to confirm that, but I'd open it in VDubMod to find out. I believe that you made a "normal" looking 720x480 image where you should have made a normal 640x480 image and then stretched it out to 720x480 by resizing it. All of this is much easier in AviSynth. But I'll do some guessing.

    Your 720x480 1:1 AVI out of Premiere was normal looking. You ran it through CCE and encoded it as 4:3, and when resized to 720x540 it wound up looking stretched vertically. So, to answer the question from the first post, it really is 720x480. Open it in VDubMod or DVD2AVI (DGIndex) to confirm.
    Quote Quote  
  6. 720x540 is what you would get if you tell the encoder a 720x480 source is 1:1 pixel aspect ratio (square pixels), and you wanted it streteched vertically to make a 4:3 picture aspect ratio on an NTSC pixel aspect ratio display. But of course, 540 lines is not a valid resolution for DVD or DV.

    You didn't delineate the steps you took but at some point you told the software to do this. In Tmpgenc for example, if you look at the Settings, Advanced tab you'll see a "Source Aspect Ratio" setting. You probably set this to 1:1 VGA (that refers to pixel aspect ratio). But your source wasn't that, it was 4:3 picture aspect ratio.
    Quote Quote  
  7. I set 4:3 in CCE 2.5 and CCE 2.6, then downloaded trial TMPG and set 4:3

    Always the same result, 720 x 540 in Windows Media Player.

    I think the operative word is "resized". I would request that anyone open their encoded m2v in Windows Media Player and see for yourself what size it is. Is all my software corrupted? Perhaps, but check it out.

    I'll make a test with input 640 x 480, output to 720 x 480, and see if that gets resized in Windows Media Player.

    I could resize my 720 x 480 DV captures to 640 x 480, but if it gets scaled up in encoding or authoring, that would seem to be a loss of original resolution.
    Quote Quote  
  8. At the risk of beating a dead horse, 720x540 is the 720x480 output from CCE after having been resized by the player, I'm almost sure. As said before, confirm by opening the .m2v in VDubMod or DVD2AVI (DGIndex). They will give you the true size. CCE doesn't resize. It just sets the DAR (4:3 or 16:9).

    I've never used Premiere, but I'm pretty sure it can take a 1:1 640x480 AVI and resize it by stretching to 720x480. However, as said before, I find AviSynth much easier for the job. Make a normal looking 640x480 AVI and then:

    AVISource("C:\Path\To\Movie.avi")
    LanczosResize(720,480)
    ConvertToYUY2() #if not YUY2 or RGB already
    empty = BlankClip() #to get rid of the audio
    AudioDub(last,empty)

    Then run that through CCE.

    If you created a normal looking 1:1 720x480 AVI, then you're doomed already, as any .mpv, .m2v, .mpg, or .vob you create in CCE and afterwards will be resized by the player and become stretched looking. I don't know if TMPGEnc can get around your problem, as I've never used it.

    Edit: I just noticed that these are DV, and my experience is with DVDs. In what form are the caps? AVI, or MPG, or something else? Could make a difference. And at 720x480, are they "normal" looking, or are they slightly squashed?
    Quote Quote  
  9. Thanks for the link to DAR, VAR, above. I will try out Virtual Dub too.

    The capture was from miniDV to Premiere, 720 x 480 DV, edited and output 720 x 480avi, input to CCE/TMPG. I wouldn't want to scale down the original capture to 640 x 480, then scale back to 720 x 480 for output to the encoders.

    We are saying the same thing, the player is resizing up to 720 x 540.
    Quote Quote  
  10. WMP can change the picture aspect ratio depending on what MPEG2 codec is installed. I had this problem once and switched to a different decoder.
    Quote Quote  
  11. The Old One SatStorm's Avatar
    Join Date: Aug 2000
    Location: Hellas (Greece), E.U.
    Search Comp PM
    In short terms, NTSC must always have 480 (or 240) vertical lines and PAL must have always 576 (or 288) vertical lines.

    When you wish "true" 4:3, then the closer thing is 640 x 480 (NTSC) and 768 x 576 (PAL).

    Computers don't use PAL or NTSC... Also they don't care about the framerate. So, they do whatever they can, to output any source in the best possible way for the monitor PC.
    La Linea by Osvaldo Cavandoli
    Quote Quote  



Similar Threads