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  1. I encoded a TV Episodes off of a DVD Disc. The episode is 720x480. I encoded it with MeGUI using x264.

    Using MeGUI I was able to determine that the Episode needs to be Cropped (to remove the black bars on the sides). There is only a black bar on the Left side of "10", so after cropping I am left with an actual picture size of 710x480. So normally I would encode the video to 710x480 and be done with it.

    However, I never really paid attention before, but noticed that MeGUI claimed those dimensions gave me an "Aspect Ration Error" of "9.69907%".

    If I resize the video to the recommended size of "648x480" (using MOD 8) the error goes down to "0.11972%".

    I have read all about the 720x480 Mpeg-2 non-square pixels which claim to be the Same as 640x480 Mpeg-4 Square Pixels. However that does not seem to be important given the ability of new TV's to Scale the Picture Correctly.

    Also, I am used to encoding Blu-Ray Movies with a DAR of 16:9 so I was encoding my 4:3 DVD Episodes with a 16:9 DAR as well since they were being viewed on a 16:9 TV (although I assume I should probably use the original DAR of 4:3 instead).



    So I decided to do a TEST:

    I encoded the same episode FOUR (4) Times and Compared the Results to the Original.


    #1 - Cropped the video by 10 (to remove the black bar on the Left Side) and encoded the Video to 710x480 with a DAR of 4:3 (which resulted in a DAR of 3:2 in MediaInfo)

    #2 - Cropped the video by 10 (to remove the black bar on the Left Side) and encoded the Video to 710x480 with a DAR of 16:9 (which resulted in a DAR of 3:2 in MediaInfo)

    #3 - Cropped the video by 10 (to remove the black bar on the Left Side) and encoded the Video to 648x480 with a DAR of 4:3

    #4 - Cropped the video by 10 (to remove the black bar on the Left Side) and encoded the Video to 648x480 with a DAR of 16:9


    RESULTS:

    When playing the videos in "Media Player Classic" on my computer:

    #1 & #2 - I noticed that the two 710x480 video were Stretched Wider that the Original, but still looked fine to me. Both looked Identical, even though I specified a Different DAR when encoding.

    #3 & #4 - The two 648x480 Looked Exactly the Same size as the Original (720x480) Video, just without the Cropped Black Bar. Again, there was NO Difference between these Two Videos even though they had a different DAR specified when encoding.


    When Played on my Samsung 16:9 1080p TV via USB:

    -All 4 Videos looked EXACTLY the same to me. They all completely filled the 1920x1080 TV Screen with no Black Bars and I could NOT find any differences between the four of them. I assume this is because the TV Automatically "Scales" the video to properly fit the screen.


    So If I am not seeing any differences, especially when played on a TV, then which of the 4 options is the Right way to encode this episode, and at the same time does it really even matter since they all seem to end up the same? Also, what is the point of picking a DAR value if I do not notice any difference between them?
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  2. Member DB83's Avatar
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    3 and 4 are closest. *

    But both should not fill a 16:9 tv screen. Only 4 should do that but even then the picture stretched look stretched.

    If 3 is filling the screen it is either horizontally stretched or vertically cropped/zoomed in.

    * Did you state if the dvd is 16:9 ?
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    Originally Posted by manofsteel31 View Post
    I have read all about the 720x480 Mpeg-2 non-square pixels which claim to be the Same as 640x480 Mpeg-4 Square Pixels.
    It's not the same!

    Instead of decreasing the number of pixels in the horizontal dimension you want to increase the number of pixels in the vertical dimension. Why would you want to decimate 720 to 640?
    Last edited by newpball; 7th Apr 2015 at 10:12.
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  4. The purpose of the DAR is to tell the player what shape to display the picture. Some players don't respect the DAR. And some players give you a choice (use the DAR, use the frame size, let you specify a standard DAR, or use whatever DAR you want). Your TV appears to ignore the DAR and simply scales everything to full screen (you should override that setting if possible, your 4:3 material should be pillarboxed to display correctly). MPCHC lets you specify the DAR with many different choices.

    The DVD MPEG 2 spec says the full 720x480 frame comprises the 4:3 DAR picture. This is at odds with the ITU spec for capturing analog video which places the 4:3 picture is in a 704x480 frame and (optionally) pads it with 8 pixels left and right to create a 720x480 frame (making the full frame 1.36 DAR, not 1.33 DAR). The reality is that nobody in the industry cares about the difference between the two specs because you can't really see the ~2 percent difference when viewing. Most DVDs made from analog tapes are captured with the ITU spec and written to DVD without correcting for the DVD spec. DVD player themselves are schizophrenic with regard to DAR. Most use the ITU spec at the composite/svideo output, but the DVD spec at the HDMI output.
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  5. If your Samsung TV is anything like mine it'll ignore any aspect ratio and either display the video as though it consists of square pixels (no aspect ratio) or I think it can be set to stretch it to fill the screen, which might look okay if the video is supposed to be displayed with an aspect ratio close to 16:9.

    For MeGUI encoding, if you enable the "clever anamorphic encoding" option you can encode at (using your example) 710x480 and MeGUI will set the aspect ratio accordingly (although as I said the TV may ignore that anyway). When anamorphic encoding is enabled MeGUI should display no aspect ratio distortion (or very little).
    Alternatively you can enable resizing (without anamorphic encoding) and resize to square pixels. Once again there should be very little aspect ratio distortion displayed after cropping and resizing. When you resize to square pixels, the video should always display correctly. With resizing enabled, by default MeGUI will resize "down" so it'll resize (for a 16:9 DVD) to something like 720x400, or you can change the resizing yourself.
    For reasons I'll never understand, MeGUI's ability to resize "up" is disabled by default. If you open the Script Creator and click on the Config button next to the AVS Profile dropdown box you'll find the option to enable "upsizing" somewhere in there (not only is upscaling disabled by default but the option to enable it is hidden away). When upsizing is enabled, MeGUI will let you resize a 16:9 DVD to something like 854x480 instead of 720x400 etc which might help to retain a little more detail.

    Technically anamorphic encoding is probably the better method if you crop and encode while simply setting the aspect ratio without any resizing, but the next best option (technically) would be to leave the height untouched after cropping and resize the width to the correct aspect ratio. Having said that, I generally end up resizing a little. What's "technically" better and what you can see are often different things.

    For a 4:3 NTSC DVD you can generally resize to 640x480 (rather than encode use anamorphic encoding at 720x480) and not see any difference. Either way though, that 4:3 encode should be displaying as 4:3 on your TV with black bars down either side. If it's not, you need to check your TV's settings. It shouldn't be stretching a 4:3 video to fill the screen (although it might also have some sort of zoom option for 4:3 that zooms in rather than stretches the picture).

    After opening a DVD for setting up an encode with the Script Creator, MeGUI automatically sets the Input Display Aspect Ratio. It defaults to an ITU 4:3 aspect ratio for 4:3 DVDs and that'll pretty much always be correct so don't change it. Just let MeGUI set the aspect ratio (anamorphic encoding) or calculate the aspect ratio distortion for you after cropping and resizing etc.
    For 16:9 DVDs the Input Display Aspect Ratio will default to ITU 16:9. If there's a reasonable amount of crud down each side requiring cropping (8 pixels or more) the DVD is probably ITU 16:9. If there's very little crud down each side (or none at all) for a 16:9 DVD it's probably not ITU and it'd be a god idea to manually change the Input Display Aspect ratio in the Script Creator to 16:9.
    "ITU 16:9" and "16:9" are slightly different. If you change the Input Display Aspect ratio, MeGUI will adjust it's aspect ratio calculations accordingly.
    Last edited by hello_hello; 7th Apr 2015 at 08:50.
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  6. When I load the video in MeGUI's AviSynth Script Creator, it tells me the INPUT DAR is "ITU 4:3 NTSC (1.367377)".



    I have never used "anamorphic encoding" before because I thought it either removed part of the picture or squeezed the top and top of the picture, neither of which sounded ideal to me.

    When I click the "anamorphic encoding" option I get a drop-down box of 5 options:

    -Resize to Selected Mod
    -Overcrop to achieve selected mod
    -encode non-mod16
    -crop mod4 horizontally
    -undercrop to achieve selected mod.

    I am not sure which option to pick, AND what "mod" I should be using. I assume its either "mod8" or "mod16"?

    As an example, if I select "resize to selected mod" then I get:

    mod8 = 656x440

    mod16 = 656x448
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  7. OK, so here are images from all the different encodes, and the original, as seen on both my computer and TV.


    ORIGINAL Video from DVD in MPC-HC:
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    648x480 with DAR = 4:3 (from MPC-HC)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    648x480 with DAR = 16:9 (from MPC-HC)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    710x480 with DAR = 4:3 (from MPC-HC)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    710x480 with DAR = 16:9 (from MPC-HC)
    [IMG][/IMG]

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


    NOW Pictures that I took from my Actual TV Screen showing the same video filling up the entire 16:9 Widescreen 1080p TV screen.

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    ORIGINAL - As seen on my TV Screen
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    648x480 DAR=4:3 (ON TV SCREEN)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    648x480 DAR=16:9 (ON TV SCREEN)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    710x480 DAR=4:3 (ON TV SCREEN)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    710x480 DAR=16:9 (ON TV SCREEN)
    [IMG][/IMG]

    --------------------------------------------------------------------------------------------------------------------------------------------------------
    Last edited by manofsteel31; 10th May 2015 at 21:49.
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  8. Member Skiller's Avatar
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    That DVD certainly follows ITU. It's already pretty obvious by the fact that you can crop 10 pixels in the horizontal, leaving you with 710 pixels which is almost exactly the digital equivalent of an analog NTSC video signal's active line width (52.656 µs * 13.5 MHz = 710.85 Pixels)


    So this means you should better forget about DAR and use PAR (Pixel Aspect Ratio) instead.

    PAR for NTSC 4:3 is 10/11.
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  9. Member DB83's Avatar
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    If the images look ok to you, your eyes deceive you.

    The lamp is the best visual guide.

    Pic 2 - the base is squashed.

    The last 2 - the base is stretched.

    A lot of people watch 4:3 stuff like that and do not notice. But as has been said 4:3 really should have side-bars on a 16:9 display.
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  10. Originally Posted by manofsteel31 View Post
    When I load the video in MeGUI's AviSynth Script Creator, it tells me the INPUT DAR is "ITU 4:3 NTSC (1.367377)".
    There is no way for Megui to determine if a DVD uses ITU or MPEG scaling. It just assumes ITU scaling.

    Originally Posted by manofsteel31 View Post
    I have never used "anamorphic encoding" before because I thought it either removed part of the picture or squeezed the top and top of the picture, neither of which sounded ideal to me.
    Your source is already anamorphic. All DVDs are anamorphic. Square pixels are not allowed by the DVD spec. So you're better off keeping the video anamorphic rather than scaling to square pixels. I highly recommend you avoid mod 2 frame sizes like 710. Some (mostly older) players will choke on that. It's best to use mod 8 frame sizes, but at least use mod 4. You should crop to 704x480 (mod 16 for both width and height) if you want the most accurate 4:3 DAR with ITU 10:11 PAR. The exception would be when you have a playback device that doesn't support anamorphic encoding. Then you want to resize to an appropriate frame for square pixel encoding. Like 640x480, 704x528, or 720x540.

    Note that the 710 pixel width that Skiller refers to assumes a 485 line frame height. Since DVD only uses 480 scan lines the correct frame width for 4:3 DAR is ~704.

    For the relationship between display aspect ratio, pixel aspect ratio, and frame size see this post:
    https://forum.videohelp.com/threads/361319-720x480-NTSC-to-720x576-PAL?p=2292828&viewfu...=1#post2292828

    Pixel aspect ratio is called sampling aspect ratio (SAR) in modern codecs. Because technically pixels are points without width or height. What is really being referred to is the distance between those points.
    Last edited by jagabo; 7th Apr 2015 at 12:00.
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  11. Originally Posted by Skiller View Post
    That DVD certainly follows ITU. It's already pretty obvious by the fact that you can crop 10 pixels in the horizontal, leaving you with 710 pixels which is almost exactly the digital equivalent of an analog NTSC video signal's active line width (52.656 µs * 13.5 MHz = 710.85 Pixels)


    So this means you should better forget about DAR and use PAR (Pixel Aspect Ratio) instead.

    PAR for NTSC 4:3 is 10/11.
    So I dont really understand that to do with that information. I checked out a few pages talking about Pixel Aspect Ratio which seemed to say that all NTSC 4:3 video was 10/11 (whatever that really even means) and I THINK what you are trying to tell me is to resize the video to the following:

    4:3 NTSC = 640x480

    ITU 4:3 NTSC = 654x480

    Although it also said based on the 10/11 calculation the video should be = 704x480


    Are all these just "standard" sizes that should be used Regardless of how much cropping is used to remove the Black Bars on the sides?

    I just changed the way I encode Blu-ray 1080p Movies to crop out the top and bottom black bars and then resize the video to the exact dimensions of the movie. For example, a 1080p movie is 1920x1080 originally (which includes black bars at the top and bottom of the screen) with an aspect ratio of 2.35:1, so if the black bars are exactly 132 pixels at the top and 132 pixels at the bottom of the screen then after cropping them out I am left with 1920x816, so I would crop and then resize that movie to 1920x816.

    That is the same philosophy I was trying to apply to a DVD as well. If its on the dvd as 720x480 and I crop out a black bar of 10 pixels on the left side then I am left with 710x480 so that is what I would resize it to.

    It sounds like it is not the same idea with DVD's. It seems like, while I should crop out the black bars like usual, I should NOT use the size of that cropped area to resize the picture. Instead I should pick a "generic" size like 640x480 to resize to instead. Is that what I should be doing?
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  12. Originally Posted by DB83 View Post
    If the images look ok to you, your eyes deceive you.

    The lamp is the best visual guide.

    Pic 2 - the base is squashed.

    The last 2 - the base is stretched.

    A lot of people watch 4:3 stuff like that and do not notice. But as has been said 4:3 really should have side-bars on a 16:9 display.

    I do notice a slight difference with the lamp now that you pointed it out, however I probably would have never noticed it if you had not directly mentioned it. For being Scaled or Stretched, the picture still looks "normal" to me. I would have expected a more Dramatic effect like something being clearly too slim or too wide, or even squeezed to the point that it was very noticable and clearly unwatchable.
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  13. Originally Posted by manofsteel31 View Post
    For being Scaled or Stretched, the picture still looks "normal" to me.
    That's because there's nothing in the frame that's of identifiable aspect ratio. Find a frame with a round ball, globe, or a car tire viewed directly from the side. Or something you know should be square, viewed head on. It will be much more obvious.

    4:3 (correct DAR):
    Click image for larger version

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    16:9 (incorrect DAR):
    Click image for larger version

Name:	16x9.jpg
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Size:	36.0 KB
ID:	31098
    Last edited by jagabo; 7th Apr 2015 at 12:43.
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  14. Member Cornucopia's Avatar
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    You just need to get over your "columna-niger-o-phobia" (irrational fear of pillarboxing).

    Scott
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  15. Member Skiller's Avatar
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    Basically, if you want to make a square pixel encode (PAR and SAR = 1:1) then you should just crop 16 pixels in the horizontal (yes, that means you have to crop off about 6 pixels of picture) and then resize to any common 4:3 resolution such as 640x480 or 704x528.

    If your TV does not display this without stretching it to fill the screen, add pillarboxing so that the frame becomes 16:9.


    Here's the math if you're interested:

    704 * (10/11) = 640


    If you crop to 710 instead you would end up with a non 4:3 DAR:

    710 * (10/11) ≈ 645.45

    Because 645.45 / 480 ≠ 4/3
    Last edited by Skiller; 7th Apr 2015 at 14:10.
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    Originally Posted by Skiller View Post
    Basically, if you want to make a square pixel encode (PAR and SAR = 1:1) then you should just crop 16 pixels in the horizontal (yes, that means you have to crop off about 6 pixels of picture) and then resize to any common 4:3 resolution such as 640x480 or 704x528.
    Why?

    After all he is transcoding to H.264

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  17. Originally Posted by manofsteel31 View Post
    When I load the video in MeGUI's AviSynth Script Creator, it tells me the INPUT DAR is "ITU 4:3 NTSC (1.367377)".
    MeGUI has a setting in it's options to tell it whether to default to ITU or not. There's no way for it to know which is correct though. If you uncheck the option it'll default to a straight 4:3 or 16:9 input display aspect ratio. My rule of thumb:
    All 4:3 DVDs are ITU. If a 16:9 DVD has lots of crud down the sides it's probably ITU. If it doesn't, it probably isn't. Most newer 16:9 DVDs are not ITU (in my opinion).

    Originally Posted by manofsteel31 View Post
    I have never used "anamorphic encoding" before because I thought it either removed part of the picture or squeezed the top and top of the picture, neither of which sounded ideal to me.

    When I click the "anamorphic encoding" option I get a drop-down box of 5 options:

    -Resize to Selected Mod
    -Overcrop to achieve selected mod
    -encode non-mod16
    -crop mod4 horizontally
    -undercrop to achieve selected mod.

    I am not sure which option to pick, AND what "mod" I should be using. I assume its either "mod8" or "mod16"?

    As an example, if I select "resize to selected mod" then I get:

    mod8 = 656x440

    mod16 = 656x448

    In the dark ages, everything had to be mod16. For x264 encoding, it doesn't matter. Pick mod2 if you like, although to be completely safe from playback problems I tend to go with a mod4 width. The height doesn't matter. Having said that, the only time I've had any problem with a mod2 width is when using a PC for playback (Microsoft API limitation that can cause ocassional problems, I think). I've never had a problem with a mod2 width using a hardware player.

    The anamorphic options pretty much do what they say. You pick the desired mod and they adjust the cropping if need be to achieve it, or the "resize to selected mod" option will resize a little instead if need be (MeGUI will also adjust the DAR accordingly if need be). The "resize" anamorphic option is the only one that lets you resize.
    "Encode non-mod16" is badly named and should be changed, but it's the option that encodes using any mod (including mod16) without adjusting the cropping or resizing. You crop as desired, and what remains is encoded.

    MeGUI will always take care of the aspect ratio when using anamorphic encoding. You don't need to think about it. Just choose whether to use an ITU input aspect ratio or not and let MeGUI do the rest. Obviously for a 16:9 DVD you'd either select, "ITU 16:9" (NTSC or PAL) or "16:9" and not 4:3 and if you select an Input DAR of 16:9 for a 4:3 DVD you'll end up with a mess too. In other words, MeGUI will pretty much always get the 4:3 or 16:9 choice correct. You only need to decide if it's ITU or not.
    When resizing to square pixels choose the desired Input DAR and adjust the cropping/resizing as required to minimise the aspect ratio distortion. MeGUI will calculate it according to the Input DAR.

    Looking at your pics it appears your video is 4:3 but your TV is even stretching the 640x480 4:3 encode to fill the screen. There must be a setting to stop it doing that. If your TV is the same as mine when playing a video via USB press the Tools button on the remote. I have three options for picture size. "Original", "mode 1" and "mode 2". The first doesn't resize, the second resizes until the height or width fill the screen, and the third stretches to fill the whole screen. Mode 1 is the mode you'd want. That should play the 4:3 video fullscreen with black bars down the sides. Try the 640x480 encode with square pixels first. When that's displaying correctly, try the anamorphic 710x480 encode. If it displays a bit wider than the 640x480 encode then the TV doesn't obey the aspect ratio and for video to display correctly you'll need to resize to square pixels rather than use anamorphic encoding.

    For the record, if you use the MPC-HC File/Save Image menu for saving screenshots, it'll save them with the wrong aspect ratio if they're anamorphic. MPC-HC will save a 4:3 720x480 DVD as 720x480 even though it's displaying it as 640x480 (4:3). For anamorphic video you need to use Alt+PrintScreen (on your keyboard) and save the screenshot manually, or use MPC-BE instead. I'm pretty sure it saves screenshots with the correct aspect ratio for anamorphic video. I think MPC-HC is confusing the issue at the moment.

    Notice how these two screenshots from your post #7 look exactly the same:
    648x480 with DAR = 4:3 (from MPC-HC)
    648x480 with DAR = 16:9 (from MPC-HC)

    That's probably because MPC-HC doesn't obey the aspect ratio when saving screenshots even though it should be displaying the video itself differently.

    648x480 with DAR = 4:3 (from MPC-HC) would be correct and it's also how the picture should be displayed.

    Notice how the pic "710x480 with DAR = 4:3 (from MPC-HC)" is slightly wider. Once again, that's probably because MPC-HC isn't obeying the aspect ratio when saving screenshots, Don't let that confuse you.

    A few pics in case the whole thing's confusing you a bit (it does at first).
    A video with an exact 4:3 aspect ratio should display like this when using your TV's USB media player, if it's displaying correctly. Whether it be 640x480 with square pixels or some other resolution with a 4:3 aspect ratio, it should display like this:

    Click image for larger version

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    If you play a 710x480 anamorphic encode with an exact 4:3 aspect ratio it should look the same as above. If your TV ignores the aspect ratio it'll display it as 710x480 worth of square pixels and the picture will be a little stretched. Not a huge difference for 4:3 NTSC, but still wrong. It probably means you won't be able to use anamorphic encoding.

    Click image for larger version

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    Currently, our TV appears to be doing something like this to the picture:

    Click image for larger version

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    Last edited by hello_hello; 7th Apr 2015 at 15:13.
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  18. Originally Posted by hello_hello View Post
    Looking at your pics it appears your video is 4:3 but your TV is even stretching the 640x480 4:3 encode to fill the screen. There must be a setting to stop it doing that. If your TV is the same as mine when playing a video via USB press the Tools button on the remote. I have three options for picture size "original", "mode 1" and "mode 2". The first doesn't resize, the second resizes until the height or width fill the screen, and the third stretches to fill the whole screen. Mode 1 is the mode you'd want. That should play the 4:3 video fullscreen with black bars down the sides. Try the 640x480 encode with square pixels first. When that's displaying correctly, try the anamorphic 710x480 encode. If it displays a bit wider than the 640x480 encode then the TV doesn't obey the aspect ratio and for video to display correctly you'll need to resize to square pixels rather than use anamorphic encoding.

    A video with a 4:3 aspect ratio should display like this when using your TV's USB media player, if it's displaying correctly.
    LOL ... Your exactly right. I had my TV set to "mode 2" which forced all videos to fill up the entire screen. As soon as I switched it to "mode 1" the video filled the screen from top to bottom but gave me the Black Bars on both sides.

    I re-tested all the encodes on the TV using Mode 1 and yes the 710x480 was wider that the 648x480 video. The 710x480 was also closest to the ORIGINAL video's size as well, but I assume thats because the original is simply being read as 720x480 by the tv and its not paying attention to the 4:3 aspect ratio.

    Also, the two 710x480 looked the same and the two 648x480 videos looked the same. So the DAR I specified as 4:3 vs 16:9 when I encoded them seems to be ignored. Either that or MeGUI is ignoring my choice because even though I encoded 2 copies of each size with different DAR values, MediaINFO lists them as the same. The 648x480 videos with DAR values of 4:3 and 16:9 both show in MediaInfo as 4:3. And both 710x480 videos show as 3:2. Not sure why that is?

    So given all that, what exactly is your recommendation? Are you saying I should just resize directly to 640x480 or 654x480 or do those numbers need to change due to how much each video or cropped, or what?


    Just tested similar videos encoded at 720x480 on 3 different apps on my iPad and they all filled the whole screen without any black bars on the sides either. Perhaps all 3 apps have default settings to automatically stretch the image to fill the screen as well. Not sure.
    Last edited by manofsteel31; 7th Apr 2015 at 15:17.
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  19. My Samsung TV's USB media player ignores any aspect ratio and displays the video as though it contains square pixels, so I have to resize to square pixels. If your TV is the same, I guess you'll need to do likewise.

    I re-tested all the encodes on the TV using Mode 1 and yes the 710x480 was wider that the 648x480 video. The 710x480 was also closest to the ORIGINAL video's size as well, but I assume thats because the original is simply being read as 720x480 by the tv and its not paying attention to the 4:3 aspect ratio.
    Probably. Try a 16:9 DVD. If it doesn't display as 16:9 the TV is ignoring the aspect ratio. I'm sure mine ignores it no matter what the video type. "Mode 2" can fix it if the video is actually 16:9, but other than that, you're out of luck.

    Also, the two 710x480 looked the same and the two 648x480 videos looked the same. So the DAR I specified as 4:3 vs 16:9 when I encoded them seems to be ignored. Either that or MeGUI is ignoring my choice because even though I encoded 2 copies of each size with different DAR values, MediaINFO lists them as the same. The 648x480 videos with DAR values of 4:3 and 16:9 both show in MediaInfo as 4:3. And both 710x480 videos show as 3:2. Not sure why that is?
    You're not confusing the Input DAR with the output are you? If you're referring to setting the Input DAR then normally you don't (aside from choosing ITU or not). The Input DAR will be what it is. You crop etc and for anamorphic encoding MeGUI should calculate the correct output DAR (it'll be listed at the top under the Script tab if you're using anamorphic encoding). There's nothing for you to set, as such. Of course if you set the Input DAR to 16:9 and don't crop or resize the output should be 16:9 if anamorphic encoding is enabled. Same if the Input DAR is set to 4:3, even if it's not the correct Input DAR.
    I'm not 100% sure what your process is there, but MeGUI will only set the correct output DAR if anamorphic encoding is enabled. If it's not enabled, you need to resize to square pixels.

    So given all that, what exactly is your recommendation? Are you saying I should just resize directly to 640x480 or 654x480 or do those numbers need to change due to how much each video or cropped, or what?
    Yes, they need to change according to how much is cropped. Resize to square pixels so the aspect ratio distortion is close to zero as possible.
    I resize to square pixels so I don't need to worry about aspect ratio issues (and because I have to if I'm using the TV's media player). That's up to you though. Either way, ideally you'd not resize the height. For square pixels, crop as required, then resize the width to give you the correct aspect ratio. For a 4:3 DVD that might be 640x480 (assuming no top or bottom cropping). For a 16:9 DVD that might be 854x480 (you'll need to enable MeGUI's up-scaling for that one as I explained earlier).
    Having said all that, I do what I want, not necessarily what's "ideal". So sometimes I resize the height a bit after cropping and/or adjust the cropping so I can resize to exactly 4:3 or 16:9 dimensions. I tend to resize PAL DVDs to 960x540 when "ideally" you'd probably resize to 1024x576 (no height resizing). In other words...... it's up to you how you do things, but for resizing to square pixels, keep the aspect ratio distortion as close to zero as you can.
    Last edited by hello_hello; 7th Apr 2015 at 15:49.
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  20. By the way, how old is your Samsung TV? Mines about 4 years old, I think. If yours is fairly new, it's disappointing if Samsung still haven't fixed the anamorphic aspect ratio problem. How hard can it be......
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  21. Mine is several years old also. I think it was one of the first "Smart TV's". I believe its the UN40d5550 and I got it in maybe 2011-2012. I know its off topic, but I am hoping the newer models will allow H264 encoding levels above Level 4.1, and eventually even H265 decoding. Not to mention fixing the aspect ratio issue your talking about.


    So if you recommend that I start encoding them to "square pixels", then my question is really "What is the Range of sizes that includes?". It sounds like 640x480 is considered to have square pixels, but I am not sure what else I have a choice of and what I should really be using to base my decision on.

    Do I just randomly keep pressing up and down, changing the width of the video, while keeping the "suggested resolution" set to mod16 until I find a size where the "Aspect Ratio Error" is as low as possible? There has to be a better way than that.
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  22. With square pixel encoding the display aspect ratio is the same as the frame aspect ratio.

    DAR = FAR * 1:1
    DAR = FAR * 1
    DAR = FAR

    So for 4:3 DAR any 4:3 frame size can be used: 64x48, 320x240,480x360, 640x480, 960x720, 1024x768, 1440x1080, 4000x3000, etc., subject to any restrictions of the player or codec.
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  23. Using an aspect ratio calculator http://www.hdslr-cinema.com/tools/aspect.php?w=636&h=480 I tried to calculate different options to maintain a 1.33 / 4:3 aspect ratio (which I assume would be considered square pixels, though correct me if I am wrong).

    If I wanted to maintain a width of 640 then the range would be: 640x480 - 640x483

    If I wanted to maintain the height of 480 then the range would be: 636x480 - 640x480

    If I was willing to change both, then I assume the possibilities could be endless. So I am not sure if I am looking at this the right way or not.

    Then again, the Input is actually listed as "1.367377" and not "1.33".
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  24. No, 640x480 is exactly 4:3. 640x481, 640x482, and 640x483 are not. And no YUV 4:2:0 encoder will accept frame dimensions with odd values. So 640x481 and 640x483 are out of the question.

    But your ITU source isn't 4:3 DAR unless you crop the frame down to 704x480. If you only crop 10 pixels off the left your video is wider than 4:3 because your frame is wider than 704. The easiest way to get the right size (if you're doing it manually) is to resize the frame to the correct DAR first (leaving the image with square pixels) then crop away any black borders. So for a 720x480 ITU frame you could resize to 654x480 then crop the black bars.

    Since you don't know what you're doing why don't you just accept that MeGUI is handling the video correctly.
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  25. Originally Posted by jagabo View Post

    Since you don't know what you're doing why don't you just accept that MeGUI is handling the video correctly.
    I dont let MeGUI pick anything for me. I only use the Script Creator to determine how much the video needs to be cropped and then minus the cropped size from the original size to get my resize values. I use one of the following Scripts for all my encodes and manually change the "Spline36Resize" value to whatever I determined it should be from the Script Creator.

    Code:
    global MeGUI_darx = 16
    global MeGUI_dary = 9
    <input>
    <deinterlace>
    <crop>
    Spline36Resize(1920,1080) # Spline36 (Neutral) mod8, mod16 h=1088
    <denoise>
    Code:
    global MeGUI_darx = 4
    global MeGUI_dary = 3
    <input>
    <deinterlace>
    <crop>
    Spline36Resize(640,480) # Spline36 (Neutral)
    <denoise>
    Code:
    global MeGUI_darx = 16
    global MeGUI_dary = 9
    <input>
    <deinterlace>
    <crop>
    Spline36Resize(720,480) # Spline36 (Neutral)
    <denoise>
    So since I manually enter that resize value for each individual encode I have to figure out how to determine it. Again, its easy with 1080p bluray content because I determine the resize value by the actual video size after cropping out of the black bars. But DVD's seem to be more complicated. I was following the same idea with DVD's by resizing a 720x480 video to 710x480 because of the 10 pixel black bar I was cropping off, but apparently I need to convert it to a square pixel size first which i am still trying to understand.

    I would think that would mean to change the 720x480 video to 640x480, then since I am cropping out the 10 pixel black bar I should resize the video to 630x480, but i am assuming that it not right.
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  26. Originally Posted by manofsteel31 View Post
    Again, its easy with 1080p bluray content because I determine the resize value by the actual video size after cropping out of the black bars.
    There's no point in resizing after cropping a Blu-ray source. The video is already the right size and square pixel. Ie, after cropping 132 pixels off the top and bottom of a 1920x1080 source you don't need to call Spline36Resize(1920, 816). The result of the cropping is already 1920x816. The resize call will do nothing but waste time.

    Originally Posted by manofsteel31 View Post
    But DVD's seem to be more complicated. I was following the same idea with DVD's by resizing a 720x480 video to 710x480 because of the 10 pixel black bar I was cropping off, but apparently I need to convert it to a square pixel size first which i am still trying to understand.
    As I stated before the easiest way to approach this is to resize the full DVD frame to a frame size that matches the DAR first, then crop away the black borders, whatever size they are. DVDs come in only two DARs: 4:3 and 16:9. So for 4:3 DVD you resize to 640x480 (or other 4:3 frame size) then crop away the black borders. For 16:9 DVD resize to 854x480 (or other 16:9 frame size) then crop.

    The only complication is that the producers of DVDs ignore the difference between ITU resizing and MPEG resizing. If they don't care why should you? But if you really want to be closer to the correct DAR resize to a 1.36:1 frame size for 4:3 DVD or a 1.82:1 frame size for 16:9 DVD, then crop away the borders.

    The difference between ITU and MPEG pixel aspect ratios is only about 2 percent. You'll never notice the difference.
    Last edited by jagabo; 7th Apr 2015 at 18:05.
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  27. Originally Posted by jagabo View Post
    Originally Posted by manofsteel31 View Post
    Again, its easy with 1080p bluray content because I determine the resize value by the actual video size after cropping out of the black bars.
    There's no point in resizing after cropping a Blu-ray source. The video is already the right size and square pixel. Ie, after cropping 132 pixels off the top and bottom of a 1920x1080 source you don't need to call Spline36Resize(1920, 816). The result of the cropping is already 1920x816. The resize call will do nothing but waste time.
    No, If I crop off the black bars but leave the profile at 1920x1080 then it will Stretch the movie vertically from 1920x816 to 1920x1080 and look terrible. The way I do it the resize has to be specified. Again, I do not use the Script Creator and allow it to make .avs files to encode my videos. I prefer to use the "One Click Encoder" and either use an existing Avisynth profile or create my own based on the ones I posted above.
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  28. Originally Posted by manofsteel31 View Post
    No, If I crop off the black bars but leave the profile at 1920x1080 then it will Stretch the movie vertically from 1920x816 to 1920x1080 and look terrible.
    That's because your script told it the DAR is 16:9. After cropping it's no longer 16:9.
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  29. Originally Posted by jagabo View Post
    Originally Posted by manofsteel31 View Post
    No, If I crop off the black bars but leave the profile at 1920x1080 then it will Stretch the movie vertically from 1920x816 to 1920x1080 and look terrible.
    That's because your script told it the DAR is 16:9. After cropping it's no longer 16:9.
    Yeah it would be the actual aspect ratio of the movie itself which would be 2.35:1 for the 1920x816 movie. Are you saying that if I removed the Spline36Resize line from the script and adjusted the DAR to 2.35:1 then it would do the same thing? If so, how would you write the DAR in the script? would it be:

    Code:
    global MeGUI_darx = 2.35
    global MeGUI_dary = 1
    meaning the entire script would look like this:

    Code:
    global MeGUI_darx = 2.35
    global MeGUI_dary = 1
    <input>
    <deinterlace>
    <crop>
    <denoise>
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  30. Leave out the DAR values entirely. MeGUI will then assume square pixel -- which is what your Blu-ray source is.
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