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  1. Member
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    Code:
    ID                          : 1
    Format                      : AVC
    Format/Info                 : Advanced Video Codec
    Format profile              : Baseline@L2
    Format settings             : 1 Ref Frames
    Format settings, CABAC      : No
    Format settings, Reference  : 1 frame
    Muxing mode                 : Header stripping
    Codec ID                    : V_MPEG4/ISO/AVC
    Duration                    : 2 h 54 min
    Nominal bit rate            : 2 000 kb/s
    Width                       : 1 920 pixels
    Height                      : 1 080 pixels
    Display aspect ratio        : 4:3
    Frame rate mode             : Constant
    Frame rate                  : 23.976 (23976/1000) FPS
    Color space                 : YUV
    Chroma subsampling          : 4:2:0
    Bit depth                   : 8 bits
    Scan type                   : Progressive
    Bits/(Pixel*Frame)          : 0.040
    Writing library             : x264 core 148 r2665 a01e339
    Encoding settings           : cabac=0 / ref=1 / deblock=1:0:0 / analyse=0x1:0x1 / me=hex / subme=1 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=0 / 8x8dct=0 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=0 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=0 / weightp=0 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc=abr / mbtree=0 / bitrate=2000 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
    Language                    : Italian
    Default                     : Yes
    Forced                      : No
    This video is reported as 1080p, snapshot shows it is really streched to 1080p, but player displays it normally as 4:3 (about 1480x1080). Mopic is true 4:3 without black lines. So why frame is supposedly 16:9, but in fact is 4:3?
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  2. Member DB83's Avatar
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    The Aspect Ratio flag (4:3) has over-ridden the Sample Aspect Ratio (16:9)


    But not all players will recognise the AR flag and stretch the image.
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  3. Any frame size can be displayed with any aspect ratio. The container can flag the aspect ratio by specifying a display aspect ratio (the shape of the displayed picture) directly or by specifying a sample aspect ratio (the "shape" of individual pixels).
    Last edited by jagabo; 28th Sep 2021 at 07:43.
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  4. Member
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    Another example: HDV, which is video from a consumer HD video camera, is 16:9 format but 1440x1080 pixels.
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  5. I'm a Super Moderator johns0's Avatar
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    1440x1080 pixels is 4:3,to be 16:9 it need to have black bars on the sides.
    I think,therefore i am a hamster.
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  6. Originally Posted by johns0 View Post
    1440x1080 pixels is 4:3,to be 16:9 it need to have black bars on the sides.
    No it doesn't. It can be flagged as 16:9 DAR or 4:3 SAR. The player should then display it as 16:9.
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  7. 1440x1080 with a 16:9 display aspect ratio is an official, if rarely seen, Bluray resolution/aspect ratio.
    https://en.wikipedia.org/wiki/Blu-ray#Video
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  8. Member DB83's Avatar
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    ^^ Important to point out the rider attached to that AR


    "c These resolutions are stored anamorphically, i.e. they are stretched to the display aspect ratio by the player or display."


    Which kinda confirms what has been already written.
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  9. Member Cornucopia's Avatar
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    Strange thing is that one can regularly find 1440x1080 - with a 16:9 DAR flag - displayed as 1920x1080. But what we see here in post #1 is 1920x1080 but with a supposed 4:3 DAR flag. Doing what? the reverse (displaying as 1440x1080)? Sounds like a case of bad re-encoding (notice the telltale x264 metadata).

    Scott
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  10. I'm a Super Moderator johns0's Avatar
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    So can a 1440x1080 video be authorized as a 16:9 video in an blu-ray authoring program?
    I think,therefore i am a hamster.
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  11. Member Cornucopia's Avatar
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    Been a while since I authored BD, but IIRC yes. Depends on the app.


    Scott
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  12. Originally Posted by johns0 View Post
    So can a 1440x1080 video be authorized as a 16:9 video in an blu-ray authoring program?
    Yes, 1440x1080 its Blu ray compliant, and when encoded with SAR=4:3 (SAR=SampleAspectRatio) the player will play it at DAR 16:9, because 4/3*1440=1920. I have done it many times. One can author it with TSMuxeR.
    It's actually an "anamorphic BluRay" which is fully legal but perhaps a bit unusual for commercial releases.
    Last edited by Sharc; 29th Sep 2021 at 13:05.
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