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  1. I have purchased some videos from both iTunes and Amazon and both use for SD 4:3 640x480 (not 720). Also many people rip MKVs on the net again in 640 (not 720). I am only talking about NTSC and 4:3.

    How is it that 640x480 is somehow the same as 720x480 and in I should rip my DVDs at 640? This whole "square" pixel thing doesn't make sense to me, as 720 is bigger then 640 no matter how you slice it.
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  2. aBigMeanie aedipuss's Avatar
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    dvd mpeg-2 uses non-square pixels so yes if you convert to the square pixel world of mpeg-4 720x480 4:3 can be encoded to 640x480 but wide screen 16/9 720x480 needs to be encoded to 854x480 or equivalent.
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  3. I'm a MEGA Super Moderator Baldrick's Avatar
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    640/480=1.333=4:3.

    720/480=1.5 and it's not 4:3, but just set the display aspect ratio to 4:3 and it will be resized to correct size in most players.


    I would rip to 720x480 if all your players supports display aspect ratio in mkv, avi, etc. Like some Samsung tvs ignores display aspect ratio in mkv, avis.
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  4. Member Cornucopia's Avatar
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    Example:
    IIIIIIIII = 9 "I" pixels (like non-square NTSC)
    and
    MMMM = 4 "M" pixels (like square computer pixels)

    So If you have one title that is 9 "I" pixels X 3 lines, and another title that is 4 "M" pixels x 3 lines, they will look like this:

    IIIIIIIII
    IIIIIIIII
    IIIIIIIII

    MMMM
    MMMM
    MMMM

    They both take up ~the same amount of space, with a similar overall outline (H+V). Yes the "I" pixels (non-square NTSC) has more HORIZONTAL RESOLUTION than the square-pixelled "M" pixels, but the overall picture is NOT bigger.

    Now, I might have a surprise for you:
    How do you know that you are getting 640x480 vs. 720x480? Which program is telling you those #s? Because if it is iTunes or Quicktime, I have news for you - It hides/fudges the truth (depending on which "aperture" and "scaling factor" it defaults to). If would be too much effort to explain in detail and show how to fix/override those defaults, so to truly know the details of what you have, you should be using MediaInfo.

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  5. Cornucopia I am using MediaInfo as Quicktime does "square" everything, so 720x480 is shown as whatever in square pixels.

    I use Apple TV and a Visio 1080 LED. I don't bother with discs anymore, though for Blu-ray quality there isn't much of an alternative there to be honest. But for my SD collection I have been using handbrake and ripping everything at 720x480 and it sets the AR. Would I lose quality if I rip in Square? I thought it would be downscaling.

    I assume my TV displays SD in 4:3 (640) and not 720, as someone said 720 isn't really 4:3 ratio.
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  6. Originally Posted by Baldrick View Post
    640/480=1.333=4:3.

    720/480=1.5 and it's not 4:3, but just set the display aspect ratio to 4:3 and it will be resized to correct size in most players.


    I would rip to 720x480 if all your players supports display aspect ratio in mkv, avi, etc. Like some Samsung tvs ignores display aspect ratio in mkv, avis.
    That's what I have been doing. What makes sense to me, is sure in native res 720x480 is displayed at 640x480 but what about upscaling? Surely the 720 would upscale better then 640? That's why shrinking it to 640 doesn't make any sense to me unless of course it is that "Square" and "wide" pixel thing but still 640 seems to be smaller and won't display as well only if you upscale, guess it doesn't matter in native.
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  7. Member Cornucopia's Avatar
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    @TubeBar, Quicktime doesn't always show "everything" as square pixels, that's just a default (that can be overridden). Here's an example of the differences: https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=106%26sec...6%26tasks=true and here's where to change that: http://support.apple.com/kb/ht4265. If 720x480 were encoded with either 8/9 or 10/11 PAR, or encoded to 4:3 DAR, it WOULD show as 640x480 square pixels, when using either the Classic or Clean Aperture.

    However, you are doing right by using MediaInfo.

    Now, your TV is a Vizio 1080 LED HDTV, so unless you've told it NOT to scale things, then everything you see on it is either 1920x1080, showing the full 16:9, or 1440x1080, showing the pillarboxed 4:3 (not counting broadcasts or pre-recorded files that already have LB/PB encoded into them). Your TV does display everything in square pixels, but it (should) understands the difference between square & non-square (unlike most PC monitors).

    The upshot of that is that all SD material is getting upscaled to fit your HD TV, whether 640x480 or 720x480 or something else (you knew this already, just probably weren't thinking about it that way). What you DON'T want to do is extra un-necessary scaling, as each change for an original will lose some quality in the rounding process of the math of doing the scaling, compounded if you also do lossy re-encodes.
    So, your TV is doing 1 level of upscaling already, but if you are ripping, etc. from the usual SD media sources (DVDs), they are originally encoded to non-square (NTSC in your case, I'm guessing) pixels, as ALL SD CE (consumer electronics) material has been (DVDs, DV, Broadcast/Cable/Sat). Only such new PC-Only-centric material as Youtube might be in square pixels (and that varies also).

    With that in mind, your choice is which to rip to: square pixels or non-square pixels? The choice is less about resolution/quality than you would think. Yes, 720 has more resolution than 640, and in a totally SD-level chain without any extra scaling, it would show as slightly finer resolution (11/10ths or 9/8ths better, depending on your standard). But that is barely noticeable even then, and with the common subsequent upscaling done for HDTVs that you would see now (as is in your case), that difference is all but washed away.

    So, I suggest that you base your decision on whether to rip to 720x480 (non-square) vs. 640x480 (square) on WHAT YOUR MEDIA PLAYER(s) CAN SUPPORT. If they can support non-square pixels, rip to 720x480 because that will be one LESS step of scaling involved, retaining just a bit extra of the original quality (as well as taking slightly less time to re-encode).
    If your player(s) cannot support non-square, then your choice is already made for you: use 640x480 square pixels, and don't worry about it.

    **********************

    Baldrick mentioned that 720/480 = 1.5, but that is ONLY its stored AR. Stored AR is not relevant to ANY calculations here, only the stored resolutions themselves (the 720 and the 480). What's relevant is the Display AR and the Pixel AR. This confuses people time and time again.
    Also, "720" is not a ratio anyway, just a number. And 720:480 using 10/11 non-square PAR IS a 4:3 DAR, just like 640x480 square pixels is.

    **********************

    Your TV may or may not allow for scaling to be turned off. If it can allow it, by turning off the scaling, you would see the SD image in only the center portion of your HD screen. And, likely, the 640 would show as 4:3 while the 720 would show unnaturally wider (because of the extra pixels) and the removal of the scaling would ALSO remove the non-square->to->square pixel adjustment. Very few TVs can do this, so I don't think you have to worry about it anyway.

    The idea that the upscale of 720->1440 may be sharper than the 640->1440 is probably true, but that difference is quite minor at that stage (at least the math is easier).

    Scott

    P.S.: Test Handbrake to make sure it is doing what you want it to correctly, don't just "assume it knows what to do right". If your source is 720x480, nonsquare and your are re-encoding to 720x480 nonsquare, make sure it retains the correct (4:3, or 16:9 if wide) DAR flag. MediaInfo is your friend here again.

    BTW, MediaInfo NEVER shows a "Stored AR" in its readout, because such a thing is never kept track of that way and doesn't exist as such in the file. It has always been derived, as a "shortcut", from the H & V stored resolutions.
    Last edited by Cornucopia; 22nd May 2014 at 13:58.
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  8. Thanks Cornucopia for the explanation and clearing that confusion up. Thanks for the QT link as I didn't know I could change that, yes I am using pro so that works.

    I have Apple TV set on 1080p so everything is displayed at 1080, 1440 or 1920 yes. I tried 480 but for some reason it doesn't display properly on my TV as everything is 4:3 (Apple IOS too) so 4:3 programs are even smaller, they have a black box on the sides inside the black box - very weird but it simply doesn't work. On my 60' Plasma Samsung it works fine but everything looks so pixelated on that either do to it being so big or poor upscaling since it's old.

    I have purchased a lot of shows from iTunes and they are all 640, but some are 16:9. I don't know why Apple doesn't use 720 except for compatible reasons for older ipod and iphones.

    Anyway Apple TV doesn't seem to have a problem displaying 720 correctly, but I should verify that by testing a square and non-square rip. If 720 is fine I will stick to that, if not it doesn't sound like 640 is all that different in quality as you said.
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  9. A quick update: I encoded 2 files exactly the same with Handbrake except one at 640x480 and one at 720x480 w/ 4:3 AR. I cannot see any quality difference whatsoever even on upscale, they appear to be identical. If space is an issue 640 is better, I have a 4TB HDD so 720 isn't going to kill me. The difference as you said is not noticeable.
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  10. Member Cornucopia's Avatar
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    OK, about what I expected (incl. Apple's problems and old Samsung rescaling woes).

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  11. Originally Posted by TubeBar View Post
    A quick update: I encoded 2 files exactly the same with Handbrake except one at 640x480 and one at 720x480 w/ 4:3 AR. I cannot see any quality difference whatsoever even on upscale, they appear to be identical.
    Try this video. Note the vertical black and white lines by the "1".
    Attached Files
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  12. Thanks jagabo, now that's exactly what I need. I will make some tests encodes and try them later and this will indeed tell me if there is anything distorted, cut off etc. Perfect!
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  13. Originally Posted by TubeBar View Post
    this will indeed tell me if there is anything distorted
    There will be. You can't turn 9 (720) alternating black and white lines into 8 (640) alternating black and white lines without some kind of distortion.

    Of course, real world video doesn't have alternating, single pixel thick, black and white lines. But you'll sometimes see features like a striped shirt, vertical blinds in the background, a sky scraper with a vertical pattern in the background, etc. When resized you'll get (more) buzzing/strobing artifacts.
    Last edited by jagabo; 23rd May 2014 at 09:54.
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  14. jagabo I encoded the files same way, this didn't have the 4:3 set so I assume I was right in setting that in Handbrake? 720x480 -> display width 640? Anyway everything checked out the same, no difference in 720 or 640 I must say, but as I said I set the AR manually as 640 so yeah it will resize when displayed on my TV.

    Actually that test pattern looked fine when I did the 16:9 stretch BUT I see the sides got cut off. I refuse to use the 16:9 stretch as it warps the hell out of video but the test pattern looked OK.

    Originally Posted by jagabo View Post
    Originally Posted by TubeBar View Post
    this will indeed tell me if there is anything distorted
    There will be.

    Of course, real world video doesn't have alternating, single pixel thick, black and white lines. But you'll sometimes see features like a striped shirt, vertical blinds in the background, a sky scraper with a vertical pattern in the background, etc. When resized you'll get (more) buzzing artifacts.
    So is it rezise issue that causes those nasty "jaggered" lines? Most of my so-called remastered old TMNT cartoons they did are filled with those, anyway to fix that?
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  15. Originally Posted by TubeBar View Post
    jagabo I encoded the files same way, this didn't have the 4:3 set so I assume I was right in setting that in Handbrake? 720x480 -> display width 640? Anyway everything checked out the same, no difference in 720 or 640 I must say, but as I said I set the AR manually as 640 so yeah it will resize when displayed on my TV.
    You didn't resize the video. You just told the player to resize differently when it upscales. Try resizing the frame to 640x480 and encoding square pixel.

    Originally Posted by TubeBar View Post
    Actually that test pattern looked fine when I did the 16:9 stretch BUT I see the sides got cut off. I refuse to use the 16:9 stretch as it warps the hell out of video but the test pattern looked OK.
    That's because your TV overscans.

    Originally Posted by TubeBar View Post
    So is it rezise issue that causes those nasty "jaggered" lines? Most of my so-called remastered old TMNT cartoons they did are filled with those, anyway to fix that?
    I think you are seeing deinterlacing artifacts. Like in the near-horizontal lines in this video?

    Name:  deint.jpg
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    Resizing artifacts, original 720 on the left, resized to 640 on the right:

    Name:  resize.png
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    And upscaled at playback:

    Name:  upscaled.png
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    Last edited by jagabo; 23rd May 2014 at 10:40.
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  16. [QUOTE=jagabo;2323168]
    Originally Posted by TubeBar View Post
    jagabo I encoded the files same way, this didn't have the 4:3 set so I assume I was right in setting that in Handbrake? 720x480 -> display width 640? Anyway everything checked out the same, no difference in 720 or 640 I must say, but as I said I set the AR manually as 640 so yeah it will resize when displayed on my TV.
    You didn't resize the video. You just told the player to resize differently when it upscales. Try resizing the frame to 640x480 and encoding square pixel.

    Not sure what you mean? I did one by chosing "none" and changed the 720 to 640. The other I did by chosing "custom" and left it at 720 but changed display width to 640.

    Originally Posted by TubeBar View Post
    So is it rezise issue that causes those nasty "jaggered" lines? Most of my so-called remastered old TMNT cartoons they did are filled with those, anyway to fix that?
    I think you are seeing deinterlacing artifacts. Like in the near-horizontal lines in this video?

    Yes that exactly it. So it is a deinterlacing problem? I have both the iTunes Store Purchased files and the DVD. I assumed the iTunes would be better but it's the same except progressive. The DVD of course is still interlaced so I can rip that and deinterlace in whatever settings can fix it?

    I stripped the DRM from the iTunes files but I doubt anything could be done to fix already progressive 23.976 video.
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  17. Member Cornucopia's Avatar
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    Umm, I'd also like to suggest that you might be not using the correct settings in Handbrake (even though you think you ARE). What are they, step-by-step, in detail?
    This way, we'll know we are on the same page.

    A MediaInfo check of rez & DAR, etc of the before & after also helps (mentioned that earlier).

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  18. Originally Posted by TubeBar View Post
    Originally Posted by jagabo View Post
    I think you are seeing deinterlacing artifacts. Like in the near-horizontal lines in this video?
    Yes that exactly it. So it is a deinterlacing problem? I have both the iTunes Store Purchased files and the DVD. I assumed the iTunes would be better but it's the same except progressive. The DVD of course is still interlaced so I can rip that and deinterlace in whatever settings can fix it?

    I stripped the DRM from the iTunes files but I doubt anything could be done to fix already progressive 23.976 video.
    They can be ameliorated in progressive video. Here's the result after two passes of Santiag() in AviSynth:

    Name:  santiag.jpg
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    Depending on the nature of your source they can be avoided completely or be very cleanly deinterlaced with QTGMC() in AviSynth.
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  19. Originally Posted by TubeBar View Post
    Originally Posted by jagabo View Post
    You didn't resize the video. You just told the player to resize differently when it upscales.
    Not sure what you mean? I did one by chosing "none" and changed the 720 to 640. The other I did by chosing "custom" and left it at 720 but changed display width to 640.
    I'm not very familiar with Handbrake's settings. Upload samples of your converted files.

    Attached are the MKV files I made. Both 4:3 DAR but one encoded 720x480 (the original frame size), the other downscaled to 640x480 before encoding.
    Attached Files
    Last edited by jagabo; 23rd May 2014 at 13:09.
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  20. Apple TV only plays mp4 (not mkv for some stupid reason). I attached the files I made and a picture of Handbrakes settings which I don't fully understand - what is PAR Width and PAR height? I left them at 1.Attachment 25339

    I'll have a look at your files, though as I said will need an mp4 container but I can do that here.
    Attached Files
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  21. Name:  Hanbrake.jpg
Views: 213
Size:  49.8 KB here's the screen,
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  22. Member Cornucopia's Avatar
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    For correct 720x480 at 4:3 DAR, your PAR Width ought to be 8 and your PAR Height 9, or, PAR Width = 10 and PAR Height = 11, depending on which standard you follow (ITU vs. MPEG). Both should look good.

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  23. Thanks Cornucopia looks like I have to recode that and retest though I am guessing it won't make a huge difference.
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  24. Member Cornucopia's Avatar
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    Pay attention to making sure circles and squares do not become ovals and rectangles.

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  25. Originally Posted by TubeBar View Post
    I attached the files I made
    You made them correctly. 640x480.mp4 is a 640x480 frame with square pixels. The vertical "1" lines show obvious distortion like the sample images I posted. 720x480.mp4 is a 720x480 frame marked as 4:3 DAR. It plays with no distortion of the thin vertical lines.

    If you view the two videos in a window they may not look too different because the player will resize the 720x480 video to 640x480 during playback (to compensate for the 4:3 DAR) -- creating similar distortion.
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  26. Originally Posted by Cornucopia View Post
    Pay attention to making sure circles and squares do not become ovals and rectangles.

    Scott
    Nope there were none I can see.

    Originally Posted by jagabo View Post
    Originally Posted by TubeBar View Post
    I attached the files I made
    You made them correctly. 640x480.mp4 is a 640x480 frame with square pixels. The vertical "1" lines show obvious distortion like the sample images I posted. 720x480.mp4 is a 720x480 frame marked as 4:3 DAR. It plays with no distortion of the thin vertical lines.

    If you view the two videos in a window they may not look too different because the player will resize the 720x480 video to 640x480 during playback (to compensate for the 4:3 DAR) -- creating similar distortion.
    Yeah QuickTime does exactly that on default settings and so does Apple TV when it displays it as they look the same. Thanks for the test pattern and all your help with this as it was a bit confusing.

    I think I have it all settled now and for anyone wondering about this hope this posts helps them.
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