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  1. Member brassplyer's Avatar
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    What would you consider an optimum bitrate beyond which is pointless overkill if upconverting SD video to Blu-Ray? Assume good quality source material that's been encoded to a 25mbps constant rate m2t file.

    Editing to clarify original SD content is 720 x 480 29.97 interlaced going to 1080i 60i, assume a lot of motion.

    DVD Architect Pro has 18mbps as a default. I don't know why they have it set at that particular number.
    Last edited by brassplyer; 27th Dec 2016 at 14:19.
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    Well, for one thing you're forgetting the "content rule" ie action movies full of explosions, grain and rapid scene changes need more bitrate than situation comedies.

    For another... SD isn't one particular thing, neither is 1080i. Are we talking 480 or 576, is the target 25i or ~30i?
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  3. Why? Just let whichever device involved that does the best upscaling do the upscaling (e.g TV, Bluray Player, Tablet/PC/Laptop or Media player - if the TV does the best job of upscaling then let that upscale, if the Bluray player does the best job then let it do the upscaling.) otherwise you'll just spend a lot of time and electricity re-encoding your files with very little (if anything) to show for it.
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  4. Member brassplyer's Avatar
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    Originally Posted by ndjamena View Post
    Well, for one thing you're forgetting the "content rule" ie action movies full of explosions, grain and rapid scene changes need more bitrate than situation comedies.

    For another... SD isn't one particular thing, neither is 1080i. Are we talking 480 or 576, is the target 25i or ~30i?
    I edited the original question per your comments - 720x480i going to 1080 60i (29.97). Assume the most demanding content.
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    The number 18 mbps I saw for AVCHD and max for DVD media.
    So if you target DVD that could be it.

    But for file to disk I imagine you could go higher from that point of view.
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  6. Originally Posted by brassplyer View Post
    Assume the most demanding content.
    Then use CRF encoding with something like --bluray-compat --vbv-maxrate 40000 --vbv-bufsize 30000 --level 4.1 --keyint 30.

    For example, I just encoded a recording of SD interstation static (a worst case scenario) upscaled to 1080i at CRF 18 and it came out to 115 Mb/s. So with noisy SD video you'll need the vbv constraints.
    Last edited by jagabo; 2nd Jan 2017 at 12:53.
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