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Index › Programming Questions & Help › Syntax Questions › Bit Shifting HSB
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Bit Shifting HSB (Read 348 times)
Johnny Ow
Bit Shifting HSB
Feb 19th, 2009, 2:35am  
I see that the RGB values of a Color can be extracted by bit shifting.  Is there a similar, fast, technique for extracting the HSB values rather than calling hue(), saturaion(), and brightness()?  I am mainly interested in the saturation right now.
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PhiLho 
Re: Bit Shifting HSB
Reply #1 - Feb 19th, 2009, 9:51am  
I fear no.
I tried:

 colorMode(HSB, 255);
 color c = color(0xFF, 0xAA, 0x55);
 println(hex(c));

It looks like colors are actually converted to RGB before storage. Which make sense: Java will internally store color information for images in RGB too.

That's why we have slower methods red green blue hue saturation brightness, to do the conversions needed by colorMode (not only mode, but also range).
The bit shifting shortcut works only in the default mode.

So in all cases, you can only convert RGB information to HSB, perhaps with an algorithm slightly faster than Processing's one (by skipping scaling), but the gain is probably marginal anyway. Well, you can try and see if it improves anything.
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Johnny Ow
Re: Bit Shifting HSB
Reply #2 - Feb 19th, 2009, 4:24pm  
Thx. for looking into it.
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