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Hyper Shinchan
14th February 2011, 05:51
I suppose that this is a general (and newbie) enough question:
I've been discussing about the colour of DVDs compared to the colour of BDs on an other, not A/V dedicated, board; as far as I can tell BD uses the same space colour (YUV 4:2:0), bit depth (8 bit) and colour matrix (usually Rec.709) used by DVD; if that's true then the only gain could be possible because of the improved codec efficiency and maximum bitrate.
Is there something else that I'm overlooking?
Blue_MiSfit
14th February 2011, 07:02
Well, not really..

If you're doing a BluRay release, you need an HD Master. You may or may not have used one for doing a DVD release. If the same master is used, the colors will be quite similar. If a new master is generated (i.e. a new telecine / film scan), it's quite possible that the look will be different.

There's nothing about HD that makes color "better". It's all still 8 bit 4:2:0, which (when done properly) is basically transparent to 4:4:4 / RGB in most cases. 10 bit would be nice though... :)

Derek
Ghitulescu
14th February 2011, 10:04
Is there something else that I'm overlooking?

Yes, the DVD uses REC 601 not 709.
SeeMoreDigital
14th February 2011, 10:12
Given more and more Blu-ray releases also come packaged with a DVD version of the same movie... How about you just compare the two ;)
yetanotherid
14th February 2011, 13:52
Yes, the DVD uses REC 601 not 709.

So does that mean the colors of a movie on a DVD must look different to the same movie on BluRay?
GodofaGap
14th February 2011, 14:54
So does that mean the colors of a movie on a DVD must look different to the same movie on BluRay?
Ignoring edge cases and rounding errors no, but it will mean if you use rec709 co-efficients on DVD video you will not get the colors as intended.
yetanotherid
14th February 2011, 17:03
Ignoring edge cases and rounding errors no, but it will mean if you use rec709 co-efficients on DVD video you will not get the colors as intended.

Cheers. I was just kind of curious as to whether the answer had anything to do with the question asked.
Ghitulescu
14th February 2011, 17:10
Cheers. I was just kind of curious as to whether the answer had anything to do with the question asked.

The question itself contained a false assumption.

All the answers are however correct, insofar the unclarity has been removed.

Watching a DVD on a SD chain should correctly display the colours. The same goes for a BD (with HDTV) on a HDTV chain, too. If one watches SD on a HDTV chain or HD on a SD chain* (or equivalent) it's the sole responsibility of the player to convert not only the definition but also the colour space according to the displaying device.

*like SD outputs of various HD players and SAT receivers.
yetanotherid
14th February 2011, 17:23
The question itself contained a false assumption.

All the answers are however correct, insofar the unclarity has been removed.

Ah yes.... I see the error of my ways now.
I missed where the original question included the assumption that both DVD and BluRay use Rec 709.

Dumb, dumb of the thread award goes to me....
Hyper Shinchan
15th February 2011, 02:32
First of all thanks for the replies.
If you're doing a BluRay release, you need an HD Master. You may or may not have used one for doing a DVD release. If the same master is used, the colors will be quite similar. If a new master is generated (i.e. a new telecine / film scan), it's quite possible that the look will be different.
Yeah, I was referring to a comparison made using the same source.
Given more and more Blu-ray releases also come packaged with a DVD version of the same movie... How about you just compare the two ;)
Do you mean packaged together? No, all BDs that I own don't have a DVD packaged together, most of them have been released separately on DVD as well but I don't own those editions.
Yes, the DVD uses REC 601 not 709.
Thank you for the correction; GodofaGap mentioned something about edge cases and rounding errors, could anyone explain something more about it?
SeeMoreDigital
15th February 2011, 10:08
Do you mean packaged together? No, all BDs that I own don't have a DVD packaged together, most of them have been released separately on DVD as well but I don't own those editions.Yes... From memory, my Blu-ray versions of Sherlock Holmes, Avatar and Blade Runner all came with DVD versions.

Sufficed to say, both versions will have been authored from the same master.

Here's an example: -

DVD = http://img33.imageshack.us/img33/4348/dvdj.th.png (http://img33.imageshack.us/i/dvdj.png/)

Blu-ray = http://img405.imageshack.us/img405/2367/blurayo.th.png (http://img405.imageshack.us/i/blurayo.png/)