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Export HD to NTSC Widescreen -- not truly 16:9

Aug 14, 2010 10:41 PM

If you export HD footage, 1080x1920 for example, to NTSC Widescreen, you end up with 720x480 with rectangular pixels that have a 1.2121 pixel aspect ratio. That means, the display is effectively 873x480 pixels, which is a a screen aspect ratio of about 16.4:9 instead of 16:9. What you end up with is the original video image squashed between thin, vertical black bars on the right and left sides (not the thick black bars you get when you display a 4:3 video in a 16:9 display).

 

If you open the video in an NTSC Widescreen Sequence, you'll see those black bars. The video image does not fill the screen.

 

This is easily fixed: change the Scale Width value to 102.3 (uncheck Uniform Scale). That puts the image portion of the clip into the proper aspect ratio (and shoves the black bars off the left and right sides of the screen). But I'd rather change the scale of all the clips in a project.

 

Since NTSC has to be 720x480 pixels, if you want to display something at a 16:9 ratio, the pixel aspect ratio should be 1.185 instead of 1.2121.

 

Perhaps an Adobe engineer can explain why exporting HD to NTSC Widescreen creates a video with black vertical bars and how a 720x480 (with rectangular pixels with a 1.2121 aspect ratio) clip can be considered as having a 16:9 aspect ratio.

 

Thanks,

 

Jeff Sengstack

 
Replies
  • Currently Being Moderated
    Aug 14, 2010 11:45 PM   in reply to Sengstack

    Since NTSC has to be 720x480 pixels, if you want to display something at a 16:9 ratio, the pixel aspect ratio should be 1.185 instead of 1.2121.

     

    Dude, I came up with the same answer.  Despite some offered explanations, I find it hard to ignore the math here.  16 divided by 9 = 1.777.  Multiply that by 480 and you get a square pixel "widescreen" resolution of of 853.333.  Divide that by the 720 you're limited to and we end up with the correct PAR of 1.185.

     

    I don't get why that's not recognized.

     
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    Aug 15, 2010 12:37 AM   in reply to Sengstack

    Adobe does it the right way. A PAR of 1.185 will give a slightly distorted image in DV widescreen. This was fixed in CS4.  It can be very confusing, but the root of the matter is that a DV frame is not really 4:3 or 16:9 - there is some padding at the sides (18 pixels) that wasn't intended to be part of the visible frame. HD footage doesn't have these extra pixels, so when you go from HD to SD, you see these little pillars on the side. You can change the PAR is you want, but the result is slighly distorted - fatter - than reality. These links can explain it much better than I can:

     

     

    http://www.bbc.co.uk/commissioning/tvbranding/picturesize.shtml

     

    http://help.adobe.com/en_US/AfterEffects/9.0/WS3878526689cb91655866c11 03906c6dea-7f3aa.html

     

    http://www.lynda.com/home/Player.aspx?lpk4=40550

     
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    Aug 15, 2010 5:17 AM   in reply to Bill Engeler

    These black vertical bars are easily fixed in the export settings.

    On the top left hand side you will find CROP.

    Crop a few pixels of the top and bottom to make it fit.

    For PAL its 13 by 13.

    After cropping you can check it in the output window.

     

    crop on export.png

     
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    Aug 15, 2010 4:39 AM   in reply to Bill Engeler

    I really like that Lynda video.

     

    http://www.lynda.com/home/Player.aspx?lpk4=40550

     

    They really have some good videos.

     

     

    Thanks Bill :  GLenn

     
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  • Currently Being Moderated
    Aug 15, 2010 8:12 AM   in reply to Bill Engeler

    Adobe does it the right way.

     

    I'm still not seeing that myself.

     

     

    A PAR of 1.185 will give a slightly distorted image in DV widescreen.

     

    According to the math, it provides a prefect, properly sized image. In fact, in order to crop a 16:9 image into a proper 1.85 film aspect*, you need to use the proper math listed earlier.  Using the current PAR, you'll end up cropping too little.

     

     

     

     

    *(Another technocrat error, if you ask me, was making HD such a weird aspect ratio.  All they needed was to lose 20 extra pixels (1920 x 1040) to get the proper 1.85:1 aspect ratio of film.)

     
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  • Currently Being Moderated
    Aug 15, 2010 12:25 PM   in reply to Sengstack

    As I said, it gets confusing, and I'm not an expert - that's why I provided links.  I can perhaps try to answer some of the points you brought up however;

     

    1) The DV frame is always 720 x 576 (PAL). It's just not exactly 4;3 or 16;9. 702x576 will give those exact aspect ratios, and is in the same proportion as HD frames. HD reduced to DV will only use 702 pixels across. to not distort the image. 720x 576 is a little wider than 4;3 or 16;9.

     

    2) There's no truncating. It's just that HD 1920x1080 is a slightly narrower rectangle than DV widescreen, so it doesn't quite fit right when reduced proportionaly.

     

    3) It's Sunday night and I'm on holiday. No math tonight.

     

    4) Ann Bens provided an easy way to avoid the bars.  It does distort the image a little, but it's barely noticeable. The other way is to enlarge the image a few percent when transcoding in AME. (I'm not at my editing PC right now, and I forget the details). This might increase rendering time, but I can't say for sure. That doesn't quite answer your last question, I know.

     

     

     
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  • Currently Being Moderated
    Aug 15, 2010 12:35 PM   in reply to Sengstack
    function(){return A.apply(null,[this].concat($A(arguments)))}

    Sengstack wrote:

     

    Ann,

     

    I do not think cropping leads to the desired result.

     

    When you crop in the Export Settings dialog box, you are cropping the image area. So, when you export HD to NTSC Widescreen, you still end up with video that has those two vertical black bars. And if you cropped the left and right sides, that will simply expand the width of the vertical black bars. If you crop only the top and bottom, you still get those vertical black bars plus end up cutting off image area at the top and bottom.

     

    The goal is to not have those vertical black bars that P Pro adds to HD footage when exporting to NTSC Widescreen.

     

    Jeff

     

    Just try it, it works. Those few pixels you will hardly miss.

     
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    Aug 15, 2010 5:01 PM   in reply to Sengstack

    I'm sorry that I can't get into this thread in depth right now. It's Sunday evening, and I've got three minutes before my wife and I need to leave to meet friends for dinner. But I can at least point to the page that I wrote to deal with these questions for After Effects CS4:

    http://blogs.adobe.com/toddkopriva/2009/07/pixel-aspect-ratios-in-afte r-e.html

     

    Premiere Pro CS4 had the same PARs as After Effects CS4, so it seems odd that this is only coming up in the Premiere Pro context now.

     

    The one thing that I'll say before running off is that you have to do your frame aspect ratio calculations based on the image area (clean aperture) not the production aperture. It's the failure to make that distinction that caused all of this confusion in the first place.

     

    Oh, and note that the Foundry and Apple are using the corrected PARs now, too.

     

    If this conversation is still going on tomorrow afternoon (when I emerge from a day of meetings) I'll see if I can help clear up any remaining questions.

     
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  • Currently Being Moderated
    Aug 15, 2010 10:39 PM   in reply to Sengstack

    >>>2) HD 1920x1080 is exactly a 16:9 format.NTSC Widescreen is supposed to be 16:9.

     

    This is the heart of the matter - NTSC Widescreen (and PAL widescreen) is not 16:9 - it is 16:9 plus a few pixels on the sides.  Thus it is not the same shape as an HD frame. Imagine the slightly skinnier HD frame zooming down into the NTSC (or PAL) widescreen frame. At some point the top and bottom of both frames will exactly align, but the shrunken HD frame, being a little skinnier, will not fill the smaller frame at the sides.

     

    Now in order to avoid the gap at the sides, you could not shrink the HD frame as much, but this will cause the loss of some of the image at the top and the bottom.  (I wish I could draw a picture right now).  Adobe, and others, have decided that the black pillars at the side are preferable to chopping the image.

     
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  • Currently Being Moderated
    Aug 16, 2010 3:41 AM   in reply to Sengstack

    It's because thay are not extra frames - it's just that since the HD frame is not the same shape as the DV frame, it doesn't fill it all the way; it leaves a little on the side when it is reduced.  Since widescreen DV footage is recorded in the camera as 720 x 576 (or whatever for NTSC), there's no reduction, and of course it fills all 720 pixels across.

     
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  • Currently Being Moderated
    Aug 16, 2010 7:38 AM   in reply to Bill Engeler

    This thread came up when researching the problem I am attempting to deal with. I have read all the linked articles and have a basic understanding of PAR and the related issues. I am attempting to convert 1920x1880 (PAR 1.0) footage to DV PAL Widescreen and also get the left and right vertical black bars. Of more concern to me is this: I did a test where I carefully superimposed the Safe Margins on the orginal HD footage before the conversion. After the conversion to PAL Widescreen I noticed that the horizontal Safe Margins were perfect, but the vertical (left right) margins had shrunk by about the same width as the black bars, showing that the DV picture was now squished horizontally from the original.

    My product is educational and the adherance to correct Safe Margins, particularly Safe Title, is critical. This also means that additional materials (like menus) created for the DV in DVD frame sizes do not line up with converted footage.

     
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    Aug 16, 2010 10:45 AM   in reply to tjbonjour

    I had a project that was shot 16:9 dv ntsc. At some point it was worth my trying to export this project as 16:9 using a 4:3 space...and  FORCE a letterbox type of frame space in the final product. Which did leave black on top and bottom, but didn't distort the video or have black bars on left and right.

    To do this I made a new project at 4:3, and put the 16:9 footage in that project and scaled the 16:9 down to fit the frame left and right. ( leaving the black bars on top and bottom). exporting THAT got me what I wanted in the final product for that particular situation.

     

    Weird, but it worked. Not sure if this clicks with anyone dealing with this problem here, but worth mentioning

     
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    Aug 17, 2010 9:10 AM   in reply to Todd_Kopriva
    you have to do your frame aspect ratio calculations based on the image area (clean aperture) not the production aperture.

     

    That is a question I still have.  Unless I misunderstand those terms, it seems that with digital video, there is no need to distinguish between the two.  With DV, you get the whole image, visible and "clean".  Seems like the distinction is only really necessary for older analog systems.  So why is that applied to digital video where it isn't necessary, and thus provides incorrect aspect?

     
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  • Currently Being Moderated
    Aug 17, 2010 9:12 AM   in reply to Bill Engeler
    NTSC Widescreen (and PAL widescreen) is not 16:9 - it is 16:9 plus a few pixels on the sides.

     

    It would seem that may be so only because an incorrect PAR is used.  Were it the proper 1.185, I can't see where extra pixels would be required.  (Well, maybe part of one to get it up to the full 854.)

     
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    Aug 17, 2010 9:54 AM   in reply to Jim Simon

    Seems like the distinction is only really necessary for older analog systems.  So why is that applied to digital video where it isn't necessary

    Unless I'm mistaken, it's all about broadcast, broadcast, broadcast per the BBC standard.

     

    -Jeff

     
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    Aug 17, 2010 10:04 AM   in reply to Jeff Bellune

    Seems like the distinction is only really necessary for older analog systems.  So why is that applied to digital video where it isn't necessary

    Unless I'm mistaken, it's all about broadcast, broadcast, broadcast per the BBC standard.

    Additional to that, remember that digital video recording predates digital broadcasting and digital displays. In other words, digital video (DV) was originally destined for analog broadcasting to analog TV sets; to compensate for that, the whole production vs. clean aperture thing got swirled into the mix.

     
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    Aug 17, 2010 10:25 AM   in reply to Jeff Bellune

    -----------------

     

    you have to do your frame aspect ratio calculations based on the image  area (clean aperture) not the production aperture.

     

    ---------------------

     

    page 4...this link

    http://www.panavision.com/publish/2007/12/10/GenesisFAQs20071207.pdf

     

    -----------

    My take on this is that CCD's that are full size for 35mm film ( beginning of aspect ratios for a lot of stuff ) there is less fudging re: transforming a smaller chip size to the correct exact image size, that the image size derrived from the real camera recording may not be exactly the "production" aspect ratio sizes...or something like that... It is confusing to me also, as I have no video cameras, digital or otherwise, and don't shoot anything but still film.

     

    I think ( not sure but think I read ) that the red camera actually has a CCD "larger" than the genesis, so it actually is capable of recording higher resolutions than typical 4.4.4 production dimensions....but how that works into "clean" image area and aspect ratio is confusing to me also...

     

     

    To further confuse me, this article has info on exact number of lines broadcast for pal and ntsc...

     

    note THIS in the article ===------------------------------------------------------

    NTSC Video

     

    • 525 scan lines per frame,  30      frames per second (or be exact, 29.97 fps, 33.37 msec/frame)
    • Interlaced, each frame is      divided into 2 fields, 262.5 lines/field
    • 20 lines reserved for control      information at the beginning of each field
      • So a maximum of 485       lines of visible data

    ---------------------------------------------------------------------- -----------------

     

     

     

    Basics of Video

    • Analog video is represented      as a continuous (time varying) signal.
    • Digital video is represented      as a sequence of digital images.
     

        Types of Color Video Signals


    • Component video --      each primary is sent as a separate video signal.
      • The primaries can       either be RGB or a luminance-chrominance transformation of them (e.g.,       YIQ, YUV).
      • Best color       reproduction
      • Requires more       bandwidth and good synchronization of the three components
    • Composite video --      color (chrominance) and luminance signals are mixed into a single carrier      wave. Some interference between the two signals is inevitable.
    • S-Video (Separated      video, e.g., in S-VHS) -- a compromise between component analog video and      the composite video. It uses two lines, one for luminance and another for      composite chrominance signal.

     

        Analog Video


    The following figures are from A.M. Tekalp, "Digital video processing", Prentice Hall PTR, 1995, NTSC.

    NTSC Video

    • 525 scan lines per frame, 30      frames per second (or be exact, 29.97 fps, 33.37 msec/frame)
    • Interlaced, each frame is      divided into 2 fields, 262.5 lines/field
    • 20 lines reserved for control      information at the beginning of each field
      • So a maximum of 485       lines of visible data
      • Laserdisc and S-VHS       have actual resolution of ~420 lines
      • Ordinary TV -- ~320       lines
    • Each line takes 63.5      microseconds to scan. Horizontal retrace takes 10 microseconds (with 5      microseconds horizontal synch pulse embedded), so the active line time is      53.5 microseconds.


    Digital Video Rasters

    • Color representation:
      • NTSC uses YIQ color       model.
      • composite = Y + I cos(Fsc       t) + Q sin(Fsc t), where Fsc is the frequency of color subcarrier

    PAL Video

    • 625 scan lines per frame, 25      frames per second (40 msec/frame)
    • Interlaced, each frame is      divided into 2 fields, 312.5 lines/field
    • Uses YUV color model

     

     

     

        Digital Video


    • Advantages:
      • Direct random access       --> good for nonlinear video editing
      • No problem for       repeated recording
      • No need for blanking       and sync pulse
    • Almost all digital video uses      component video

     

     

    Chroma Subsampling

    • How to decimate for      chrominance?

    • 4:4:4 --> No chroma      subsampling, each pixel has Y, Cr and Cb values.


    4:2:2 --> Horizontally subsample Cr, Cb signals by a factor of 2.

    4:1:1 --> Horizontally subsampled by a factor of 4.

    4:2:0 --> Subsampled in both the horizontal and vertical dimensions by a factor of 2. Theoretically, the chroma pixel is positioned between the rows and columns as shown in the figure.

    • 4:1:1 and 4:2:0 are mostly      used in JPEG and MPEG (see Chapter 4).
     

    CCIR Standards for Digital Video

    (CCIR -- Consultative Committee for International Radio)

                           CCIR 601       CCIR 601         CIF         QCIF
                            525/60         625/50   
                             NTSC         PAL/SECAM       
    --------------------  -----------    -----------   -----------  -----------
     
    Luminance resolution   720 x 485      720 x 576     352 x 288    176 x 144
     
    Chrominance resolut.   360 x 485      360 x 576     176 x 144     88 x 72
     
    Color Subsampling        4:2:2          4:2:2         4:2:0        4:2:0
     
    Fields/sec                60             50            30           30
     
    Interlacing               Yes            Yes           No           No 
     
    • CCIR 601 uses interlaced      scan, so each field only has half as much vertical resolution (e.g., 243      lines in NTSC). The CCIR 601 (NTSC) data rate is ~165 Mbps.
    • CIF (Common Intermediate      Format) -- an acceptable temporary standard
      • Approximately the VHS       quality
      • Uses progressive       (non-interlaced) scan
      • Uses NTSC frame rate,       and half the active lines of PAL signals --> To play on existing TVs,       PAL systems need to do frame rate conversion, and NTSC systems need to do       line-number conversion.
    • QCIF -- Quarter-CIF
     

    ATSC Digital Television Standard

    (ATSC -- Advanced Television Systems Committee) The ATSC Digital Television Standard was recommended to be adopted as the Advanced TV broadcasting standard by the FCC Advisory Committee on Advanced Television Service on November 28, 1995. It covers the standard for HDTV (High Definition TV).

    Video Format

    The video scanning formats supported by the ATSC Digital Television Standard are shown in the following table.

    Vertical Lines

    Horizontal   Pixels

    Aspect Ratio

    Picture Rate

    1080

    1920

    16:9

    60I 30P 24P

    720

    1280

    16:9

    60P 30P 24P

    480

    704

    16:9 &   4:3

    60I 60P 30P   24P

    480

    640

    4:3

    60I 60P 30P   24P

    • The aspect ratio for HDTV is      16:9 as opposed to 4:3 in NTSC, PAL, and SECAM. (A 33% increase in      horizontal dimension.)
    • In the picture rate column,      the "I" means interlaced scan, and the "P" means      progressive (non-interlaced) scan.
    • Both NTSC rates and integer      rates are supported (i.e., 60.00, 59.94, 30.00, 29.97, 24.00, and 23.98).
    • At 1920 x 1080, 60I (which      CBS and NBC have selected), there will be 1920 x 1080 x 30 = 62.2 millions      pixels per second. Considering 4:2:2 chroma subsampling, each pixel needs      16 bits to represent, the bit rate is 62.2 x 16 = 995 Mb/sec.

    Homepage of the Advanced Television Systems Committee (ATSC)

     
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  • Currently Being Moderated
    Aug 17, 2010 11:06 AM   in reply to Sengstack

    Long thread.  If I can distill it down correctly, the OP question is essentially asking 'why do I get letter boxing?'

     

    Essentially, the problem comes down to the fact that your source doesn't match the destination PAR.  Currently, if the source & destination PARs don't match, you get letter boxing.  Why? From a technical standpoint of 'do no harm', it's bad practice to drop pixels, and the render pipeline is trying to preserve the aspect ratio of your footage.  What you're effectively asking for is a option in AME to 'fit to fill (distort)'.

     

    Currently, as a workaround, if you plan to export to a DV preset, if you nest your HD sequence into a DV sequence, then export the nested version, now your source sequence will match the destination, and that will circumvent the need to letterbox.

     

    Cheers

     
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    Aug 17, 2010 11:47 AM   in reply to Wil Renczes

    Wil,  which is basically putting the HD into DV and scaling it down to fit the 16:9 DV..correct ?

     
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    Aug 17, 2010 1:06 PM   in reply to Colin Brougham

    digital video (DV) was originally destined for analog broadcasting to analog TV sets; to compensate for that, the whole production vs. clean aperture thing got swirled into the mix.

     

    It may have gotten swirled in previous to digital broadcast and displays, but Adobe added it after the fact.  Now that the entire pipeline is digital, that seems as good a time as any to drop some of the old analog ways and develop new standards that are more appropriate to the digital pipeline.

     

    I'm not sure Adobe did the right thing here by conforming DV to old, analog standards.  To wit:

     

    "Although the ATSC A/53 standard limits MPEG-2 transmission to these 18 formats (and their 1000/1001-rate slowed-down versions), the U.S. Federal Communications Commission declined to mandate that television stations obey this part of the ATSC's standard. In theory, television stations in the U.S. are free to choose any resolution, aspect ratio, and frame/field rate, within the limits of Main Profile @ High Level. Many stations do go outside the bounds of the ATSC specification by using other resolutions – for example, 720 × 480."

     
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  • Currently Being Moderated
    Aug 17, 2010 1:04 PM   in reply to Sengstack

    Actually the black bars is empty space. The background shows as black.

     
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    Aug 17, 2010 1:11 PM   in reply to Sengstack

    I guess you're exporting frames and opening in photoshop to measure exactly how many pixels are left and right of frame? which is square pixels..psd...

    I think the bottom line is that what you see is the result of un-exact measurements...relating to par, dar etc.

     

    And a lot of different cameras, who basically translated the japaneese company "standards" of HD ( blue ray etc) according to their not exact language translation...meaning there's a lot of leeway about application of the standard...You would think that translation of science would be more exact but it isn't.

     

    If I go from metric to feet and inches, or nautical miles to statute miles, there are discrepancies ...as the math just isnt perfect.  There is some slop in the math, no matter what you do, and the accuracy of math is sometimes in the translation of the different "systems".

     

    and this is made more obvious as you translate more than 2 things....like maybe now you are dealing with 3 things..

     

    Its a fascinating subject though...thanks for sticking it out and trying to get a definitive answer !

     
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  • Currently Being Moderated
    Aug 17, 2010 7:35 PM   in reply to Sengstack

    Jeff, I already answered your question above (not sure if you skipped over my post).  You're getting tripped up on the notion that the black bars equates to the area outside the production aperture of dv footage, and that's not the case.  This problem has nothing to do with production versus clean aperture of dv.

     

    (Tangentially, since you were asking on what you're getting during onscreen dv playback , PPro doesn't expand out production aperture to clean on playback - that would be effectively be a horizontal stretch distortion.  You're getting full 720 width in the program monitor.  If you're wondering why you're not seeing black bars on your DV  footage, it's probably because there isn't any.  Keep in mind that the 'production' aperture might not be visible on a dv camera - you'd have to be capturing from an analog signal to see production aperture.  If you're shooting on a DV device, it's likely to fill the entire width of the available image.)

     

    To repeat, the black bars are the difference between your HD aspect ratio (usually 1.5 or 1.33) and the NTSC 16:9 aspect (1.2).  To maintain the 1:1 relationship of the height & width of your HD material, letterboxing is being applied.

     

     
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    Aug 17, 2010 7:51 PM   in reply to able123

    robodog2 wrote:

     

    Wil,  which is basically putting the HD into DV and scaling it down to fit the 16:9 DV..correct ?

    Yep, exactly. Minor nuisance, I know, but at least you know exactly what you're getting for output, since you now control the panning. 

     
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    Aug 17, 2010 9:35 PM   in reply to Sengstack

    hehe...When you do that...sit down and go through this with SMPTE and NASA and MIT and ADOBE engineers and programmers ----SHOOT VIDEO....document it and edit with graphics and screenshots and math forumulas etc....

     

    Then you can bet I will be on line to BUY IT   !

     

     
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    Jun 7, 2011 5:32 PM   in reply to Sengstack

    Hi Jeff,

     

    I just run accross your post. It is old, but I recently was running in the same problems as you. It was hard to get things straight for me, but finally I found a German paper that explained everything just to the point.

     

    16:9 = 1,777...

    HD uses square pixels (PAR=1.0) and if you check the two most common HD video sizes and take your calculator 1920:1080=1,777... and 1280:720=1,777.... So both of them are 16:9 formats. (Exactly we would calculate 1920 (pixel) x 1.0 (PAR) : 1280 (pixel) x 1.0 (PAR))

     

    Now in SD we have an analog NTSC/PAL an a DV NTSC/PAL. To make it easy first, lets look at DV. The default resolution for DV NTSC is defined as 720×480, but DV doesn't us square pixel. It uses rectangular pixel. The PAR for analog(!) 16:9(!) NTSC is about 1,2154. So to convert DV pixel into the square pixel world you need to calculate 720 (pixel) x 1,2154 (PAR) = 875 square pixel.

     

    Now we are ready for the surprise: 875:480 = 1,822916...!!! DV NTSC (as PAL) are just not exact 16:9!

     

    This means you can't transform an HD frame into an SD DV frame without cropping or padding with black bars.

     

    Old Premiere and AE actually stretched the frame a little to make the transform fit. In AME you really need to choose one of three options: you can have the HD frame cropped, the SD frame padded with black or the SD frame stretched, which would distort the picture a little bit, but not much. If you don't want to have the picuedistorted or have black bars you need to crop off 28 (27) pixels from your HD surce footage. This is why often 14 pixels are each cropped of the top and the bottom. You can do this in AME using the crop tool and set the output "scale to fit".

     

    So far this explains your problem and shows you the possible solutions. To understand why DV NTSC and PAL are not 16:9 you have to dig a little bit deeper into the analog world. This would take bit longer. For a rough and simple explanation consider that analog TV (NTSC/PAL) has no pixels. It's analog. So ITU-R BT.601 defines how to get analog video into the digital world. The defined sampling frequency results in a NTSC frame of 711×486. Considering the PAR of 1,2154 you get 864:486=1,777.... So analog (anamorphic 16:9) PAL is really 16:9. Analog NTSC video convertd to DV is padded with black bars to fill to 720.

     

    This all concerns analog to digital SD-TV. The black bars were not shown on CRT TVs due to the overscan area. Nowadays LCD TVs and computer monitors can show the full 720 pixel, but still use overscan. Also video that is recorded digitally is normally recorded with the full 720 pixel. So we have video that is not in 16:9. Therefore you need to handle the transforming either with bars, cropping or distorting.

     

    Hope this helped you Jeff.

     

    Marcus

     
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