Re: [Frameworks] combining SD and HD

From: David Tetzlaff <>
Date: Sat, 4 Jun 2011 01:14:27 -0400

> Sadly, on this list there seems to be a lack of technical
> understanding of basic principles of digital art.

I know you are, but what am I.

> "Up-res'ing" or resampling resolutions is a really bad idea.

Er, in the digital realm, resolutions are constantly being twiddled around whether you know it or not. Take an HDV camera with a 1080 sensor, for example. It creates an image 1920 pixels wide. The camera, though, only has enough bandwidth to put 1440 pixels wide of info on the tape. It squeezes the image down accordingly, and some information is lost. When you view the tape or work with the file in an NLE, you are 'up-rezing' it back to 1920. HDCAM does the same thing. And this process works fine. Then there's DVCPRO HD, which records 720P as 960x720 and 1080i as 1280x1080. Nobody notices or complains.

> You'll get fuzzy, crappy video.

This would be news to the hundreds of thousands of people using upcoverting DVD players right now, who have poppped their plain old standard-def DVDs into their little boxes and are viewing pictures that are not only neither fuzzy nor crappy, but rather quite a bit more appealing than what the same disk yielded in a conventional player at it's native resolution.

> Don't do it.


What exactly happens when you convert a stream of digital images from one resolution to another higher one depends on a lot of different things: the nature of the footage, the codecs involved, the technology performing the conversion, the amount of the up-rezing... Sometimes, it does NOT work well. Sometimes it works very well. Sometimes its somewhere in between. Only with a far more detailed scenario could you predictions or prescriptions about changing resolutions (e.g. something in a form similar to 'Don't use Quicktime to convert SD-MPEG2 ripped from a DVD into an 1080P AVC-HD file. It will look fuzzy and crappy.' (And I'm just illustrating the minimow level of predictive detail wit random examples. I have no idea what that particular conversion would look like...)

> As Freya said, you can store different resolutions of video on the same Blu-Ray disc.

...If you have the right authoring tools. But lets say you only have the capability to make a BR with one title, separating titles with chapter markers. If you have good video editing software (say Final Cut Pro), there is no reason NOT to up-rez standard def original to the points where it fits inside a 720 or even 1080 HD frame pillarboxed (In the first case converting 720x480 into 960x720) because that is EXACTLY what a 720P flatpanel TV is going to do in hardware anyway.

> Forgive my apostasy, but Apple's [authoring] tools are clearly behind the curve.

Perhaps that's because Apple does not produce ANY DVD authoring toolos. Or perhaps you meant to say 'DVD authoring tools for use in OSX' In which case there is only Toast and Encore, neither of them all that great. However 'authoring' strictly speaking has nothing whatsoever to do with the quality of the video image of your content, which is a functioning of _'encoding'_ tools. And there are several quite good software encorders available for Mac...

> you might take a look at Adobe's offerings.

And you might want to shut the fuck up until you learn what the hell you're talking about, and/or learn to express yourself clearly.

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Received on Fri Jun 03 2011 - 22:14:37 CDT