oxygen
Posts: 633
Joined: Tue Sep 14, 1999 12:27 am

What Is Luminance Noise?

Tue Apr 22, 2003 1:06 am

Hi, I was just reading through some instructions of a noise reduction program, and I came across a work 'luminance noise'. What does that mean? The passage also mentioned 'Cr and Cb ' channel. What does that stand for ?
Thanks very much !
 
ckw
Posts: 4586
Joined: Fri Aug 27, 2010 12:26 am

RE: What Is Luminance Noise?

Tue Apr 22, 2003 3:42 am

Luminance noise is the term for one component of the noise generated by CCDs - this is the "grainy" look some images have. CCDs also generate chroma noise which produces red and blue specks.

Cr and Cb I think refers to a video technique of processing images (an alternative to RGB) in which colours are somehow derived by processing just the red and blue channels, plus a brightness channel - sort of like the LAB format available in Photoshop and other packages for processing photos.

Cheers,

Colin
Colin K. Work, Pixstel
 
dripstick
Posts: 2320
Joined: Sat Dec 01, 2001 9:43 am

RE: What Is Luminance Noise?

Tue Apr 22, 2003 7:52 am

Luminance noise: luminance noise is an abrupt change in brightness between pixels. Sometimes called "high frequency pitting", this type of noise appears as grain or dots in the image.

Chrominance noise: Chrominance noise is an abrupt change in the color (hue) between pixels or adjacent sets of pixels. This noise appears as small color streaks or "veins" in what should be smooth, unchanging color.


Source:http://www.ddisoftware.com/reviews/s2/
What's another word for thesaurus?
 
oxygen
Posts: 633
Joined: Tue Sep 14, 1999 12:27 am

RE: What Is Luminance Noise?

Tue Apr 22, 2003 2:50 pm

Thanks! Now I understand their difference.
 
mnsourcer
Posts: 44
Joined: Wed Apr 16, 2003 11:21 am

RE: What Is Luminance Noise?

Wed Apr 23, 2003 8:52 am

Is there a particular way to remove these types of noise, especially the Luminance noise. Seems to be a problem I constantly content with.

Thanks,

mnsourcer

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