Does uncompressed video have an associated colorspace?

the Black Monarch · Post by **the Black Monarch** » Sat May 31, 2003 7:14 pm

I can avoid some of them, just not all of them.

klinky · Post by **klinky** » Sat May 31, 2003 8:53 pm

You can have UNCOMPRESSED RGB & UNCOMPRESSED YUV. Uncompressed is not a video format. It's basically raw image data. Image data can be defined in different colorspaces. There for you can have uncompressed YUV, RGB, CMYK(if that was ever supported for video editing).

Normal UNCOMPRESSED video on a Windows machine is UNCOMPRESSED RGB data. If you look in VirtualDub, or really any other program that pops up the VfW compression dialog box it says specifically "Uncompressed RGB". It's a bunch of RGB bitmaps stacked into a AVI structure. Trythil could do the same with Quicktime on loonix. A bunch of YUV bitmaps stacked inside a Quicktime structure.

Oh and HuffYUV will compress RGB data in RGB format as well. It will maintain RGB colorspace. It won't compress as well as YUV but it will work. Just make sure you don't have RGB setup to "Convert to YUY2" in the codec configuration.

~klinky

NicholasDWolfwood · Post by **NicholasDWolfwood** » Sat May 31, 2003 9:01 pm

the Black Monarch wrote:I can avoid some of them, just not all of them.

How?

DVDs are YV12. Then take it into Premiere and it's converted on the spot to RGB. Any codec for distro you use is in YUY2, therefore you cannot avoid colorspace conversions unless you use Linux-Cinelerra, and even then there's YV12 -> YUY2

the Black Monarch · Post by **the Black Monarch** » Mon Jun 02, 2003 12:44 pm

Yeah, but It's better than going through YV12 (DVD) -> YUV (Huffy) -> RGB (Premiere) -> YUV (huffy) -> RGB (Vdub) -> YUV (distro) bullshit. That's what I mean by avoiding SOME conversions.

Zarxrax · Post by **Zarxrax** » Mon Jun 02, 2003 2:03 pm

But... huffy can do rgb too

Tab. · Post by **Tab.** » Mon Jun 02, 2003 3:10 pm

uh.. all distro codecs are YV12
YUY2/YV12 technically are forms of compression, but then so is interlacing. Not the same as perceptual or redundancy compression which is generally what we mean when we say compression nowadays. But even so YUV can be a completely non-compression based colorspace in 4:4:4.

the Black Monarch · Post by **the Black Monarch** » Mon Jun 02, 2003 10:08 pm

YV12, YUV, YUY2, whatever, the point is that it's not RGB.

How the hell is interlacing a form of compression?

Tab. · Post by **Tab.** » Mon Jun 02, 2003 10:32 pm

hello. How do you make 60 fps in half the bandwidth? Interlacing. By playing on people's eyes the geniuses who invented television created a way to halve the horizontal resolution of the signal while still retaining a full picture and doing it at 60hz to boot. Like I said, not the same as we think of digital redundancy and perceptual coding, but compression nonetheless. Same with YUY2/12. Compression independent by nature, yet a form of compression itself. Store half to 1/4th the chroma resolution because the eyes don't detect it as clearly as opposed to the full chroma and luma signal. Similar to interlacing I suppose but color channel based and not entirely resolution based.

SS5_Majin_Bebi · Post by **SS5_Majin_Bebi** » Mon Jun 02, 2003 11:03 pm

Yeah.

What he said.

the Black Monarch · Post by **the Black Monarch** » Thu Jun 05, 2003 4:07 am

Dude... turning 30 frames per second into 60 half-frames per second is NOT compression. Nothing is being compressed. Nothing is smaller after interlacing than before. The same amount of data is being used to describe the picture. The only thing that's changed is that the information is sent in more and smaller increments. That's like saying that you can compress a person by cutting him or her in half. Or that you can compress coarse sand by grinding it up into finer sand.

YUV colorspace is something that I never argued about with you, so don't act like I did.