Footage filmed on 50i Digibeta put on Blu - Ray

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Nintembo
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Joined: Jun 22 2004

Does this possess a visual bennifit over standard hardware encoded DVD?

Alan Roberts
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Why would you want to bother?

DVDs store SDTV in H.262 MPEG2. Digibetas record SDTV. A perfect match.

BluRays store HDTV in H.264 MPEG4.

A data file is a data file, whatever medium you store it on.

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Nintembo
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But what about compression issues with putting content on a standard DVD?

Alan Roberts
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You got all the answers already, but haven't answered my question, why would you bother?

Get my test cards document, and cards for 625, 525, 720 and 1080. Thanks to Gavin Gration for hosting them.
Camera settings documents are held by Daniel Browning and at the EBU
My book, 'Circles of Confusion' is available here.
Also EBU Tech.3335 tells how to test cameras, and R.118 tells how to use the results.

Ben Longden
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Joined: Jun 10 2009

Depends.... if you want to pay 50c for a blank DVD or $9 for a blank Blu-Ray disc...

Ben

asdv
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Joined: Jun 27 2003

I am also wondering if there is a way to use a Blu-ray disc as a better quality playback from a standard definition source in venues using HD projection. Blu-ray players upscale DVD to HD quite well but it would be great to give them something better than a DVD spec mpeg2 video to do it with.

Encoding to H264 at higher level profile preserves the colour sampling much better eg. 4:2:2 and 10-bit or even better, but I have been unable to find out exactly what chroma sampling and profile level(s) is allowed within the domestic Blu-ray spec.

Alan Roberts
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All disc formats are 4:2:0 as far as I'm aware. Up-converting SD footage to HD, and then compressing for BD will not make the pictures look better, they'll just occupy more megabytes.

You might get a slight advantage doing it that way, if the quality of your upscaling is better than that of the player, but upscaling's pretty easy to do, so I wouldn't expect it to be worthwhile.

Get my test cards document, and cards for 625, 525, 720 and 1080. Thanks to Gavin Gration for hosting them.
Camera settings documents are held by Daniel Browning and at the EBU
My book, 'Circles of Confusion' is available here.
Also EBU Tech.3335 tells how to test cameras, and R.118 tells how to use the results.

asdv
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Joined: Jun 27 2003

Thanks Alan. Yes, I just finally found a reference to BD encoding being always 8-bit 4:2:0 - same as DVD. I guess it was naive to expect better.

I wasn't thinking of upscaling the SD before encoding to BD - rather hoping a BD player might be able to read an SD video stream file encoded at BD's roughly 4x higher rate than a DVD can manage.

But like you say, if the advantage is only in the data rate and not any improved colour sampling then it's likely to be not worth the trouble.

Alan Roberts
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Certainly not worth the trouble. The only advantage of using a BD player is that it can do a decent up-scaling from DVD. The only advantage of putting SD onto BD is that you get much more data capacity. None of this will make the SD pictures better, so you might as well stick to DVD, it;s cheaper, and the BD player will still do the decent up-scaling if it can.

Get my test cards document, and cards for 625, 525, 720 and 1080. Thanks to Gavin Gration for hosting them.
Camera settings documents are held by Daniel Browning and at the EBU
My book, 'Circles of Confusion' is available here.
Also EBU Tech.3335 tells how to test cameras, and R.118 tells how to use the results.