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Compression: Square pixel aspect ratio only?

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Mark
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Do I need to change from my HDV native 1440x1080 (0.75 pixel aspect ratio) to 1920 x 1080 (square pixel)? This seems to be the case according to the HDCompact UsersGuide "Most HD sources (HDCAM, HDV etc) set the resolution to 1440x1080. Therefore, if you’re creating 1080i or 720p content, you need to click Change next to the appropriate field and adjust the settings for your content".

Also do I need to use mp3 audio in my muxed MPEG2 transport stream file? In some places in the documentation this is stated in others the mp2 audio (MPEG-1 Audio layer 2) is acceptable.
p.s. I'm using Apple Compressor.
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  • 0
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    RokuLyndon


    mp2 audio is what you should use for an mpeg2 video. You can still use 1440x1080, but the video will have bars if it's not scaled. If you plan on outputting to 1080 on the brightsign, and you're creating the content, then you should use a full 1920x1080 if possible.
  • 0
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    Mark


    After yesterday's successful test I'm now able to work more on tweaking my compression for best quality. Here is my setup: HDV1080i60 source material; no zones needed; compression via Apple Compressor; HD210; and Sony Bravia 32" 16:9 720p resolution LCD panel (1366 x 768) with HDMI connection (1080/60p capable). What do you advise I output and set mode to? From the VideoQualityTechnote.pdf 1920x1080x29.97p seems to be the best quality option, yes? Thanks again RokuLyndon.
  • 0
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    RokuLyndon


    Ideally, you want the content to be progressive.



    If you want to use 1080, then 1080 @ 29.97 is the best output from the brightsign, but not all displays support 29.97.
  • 0
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    Mark


    If 1920x1080x29.97p isn't supported, what would you recommend as second choice for my video (again source HDV1080i60 ending on 1366 x 768 TV) 1920x1080x60i? 1360x768x60p? 1280x720x29.97p?

    (I'll be working on this tomorrow).
  • 0
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    RokuLyndon


    If you are outputting at 1360x768, then your content should be either 1280x720 at 30 frames or 1280x720 at 60 frames. Both should work equally well.
  • 0
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    Mark


    "RokuLyndon" wrote:

    If you are outputting at 1360x768 ...


    To clarify, when you say outputting you are referring to the display/the TV? There are 4 components: footage source (HDV), content (video file played back), BrightSign video mode, and display.



    If yes, then to recap you are recommending 1920x1080x29.97p (video mode and content) as first choice and 1280x720x29.97p and 1280x720x60p as second choices?



    Hopefully, I'm not being too much of an exacting pain in the @*^!
  • 0
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    RokuLyndon


    If the monitor supports 1920x1080 at 29.97 then:

    1920x1080x29.97p (video mode and content) as first choice





    As the video quality document you read states, you frame rate you use for the video should be a factor of setting you use for the output. So, if you're using 720p as the setting on the display. Since that's only available at a setting of 60 (1280x720x60p, for example), then your source would need to be at 30 frames or at 60 frames.



    I mentioned 720p specifically because if you are using 1360x768, the 720p content will play without scaling.



    If you are definitely using 1920x1080 resolution on the display, then your content should be 1080 as well.



    If your display will be set to 1920x1080x60p, then your content can be 1920x1080 at 30fps or 60fps.



    If your display will be set to 1920x1080x50p, then your content can be 1920x1080 at 25fps or 50fps.
  • 0
    Avatar
    Mark


    Hmm, I though I was approaching an understanding - now I wonder if I'm further away.

    "RokuLyndon" wrote:

    If the monitor supports 1920x1080 at 29.97 then:
    1920x1080x29.97p (video mode and content) as first choice

    Clear. I'll try this first.

    "RokuLyndon" wrote:

    As the video quality document you read states, you frame rate you use for the video should be a factor of setting you use for the output. So, if you're using 720p as the setting on the display.
    Since that's only available at a setting of 60 (1280x720x60p, for example), then your source would need to be at 30 frames or at 60 frames.

    I'm not sure what you mean by setting on the display. My display has no 720p setting. It is a 720p (1366 x 768) panel. Yes, 60p is the only variant 720p for my display and my content should be a variant of that.  If I go with 720p content I think I'm best compressing 30p (29.97 frame) content as my original source footage is HDV1080i60.

    "RokuLyndon" wrote:

    I mentioned 720p specifically because if you are using 1360x768, the 720p content will play without scaling.

    I wondered about this and information online is equivocal. I'll go with your expertise on this: 1280x720 content does not scale when played on 1360x768 monitors.

    "RokuLyndon" wrote:

    If you are definitely using 1920x1080 resolution on the display, then your content should be 1080 as well.
    If your display will be set to 1920x1080x60p, then your content can be 1920x1080 at 30fps or 60fps.
    If your display will be set to 1920x1080x50p, then your content can be 1920x1080 at 25fps or 50fps.


    Well this is helpful in general and does make sense to me, though is not specifically pertinent. We are definitely not setting our TV display to 1920 as our 720p display doesn't do this. I assume when you say display you mean TV monitor, not BrightSign video mode?? (If you DO mean video mode, then I get what you are saying  - keep your content a variant of the video mode. Though I would go with 1920x1080x29.97p video mode and content).



    So ... I'll first try 1920x1080x29.97p (video mode and content). If that doesn't work I'll go with 1280x720x60p video format with 1280x720x29.97p content. Do I now have this right?
  • 0
    Avatar
    RokuLyndon


    Originally, when you asked, I thought your display supported 1920x1080, but if you are saying it doesn't, then there's no point in trying content at 1920x1080x29.97.



    Just use 1280x720x60p as the output setting on the brightsign, for your screen, with content at 1280x720x29.97.
  • 0
    Avatar
    Mark


    Yep its a 720p monitor - native 720p. It does support 1920x1080 in that it can play back 1920x1080 content. Semantics. I agree though 1280x720x60p makes most sense as that is essentially the resolution of the screen. I was tending to favour this resolution. I'm glad to have this settled.



    I have a few minor questions which might warrant a new thread. If you would prefer I post these as a new thread, just say.

    1. I was impressed to see the media playing in sync at 33Mb/s on the HD210's. Unfortunately, I can't use this high of a bit rate as my 4 hour video work is limited by the storage capacity not the HD210's bitrate. So, I'm in the process of working out the highest bit rate I can fit onto my 32GB cards. How much storage overhead should I leave on the class6 SDHC cards with this player?

    2.  I read somewhere here that fat32 is recommended for best playback or sync or something. Could you please elaborate a bit.

    3.  Is hot swapping the flash advisable or does one always power down before yanking the SD?



    Thanks again RokuLyndon.
  • 0
    Avatar
    RokuLyndon


    I don't think you need to leave any storage overhead on the flash card. The unit doesn't use the flash card for anything but file storage. Fat32 is pretty common, but if you have a 4GB video, you'll need to use NTFS. You should power down before pulling the card out.
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