• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: floats & Color APIs
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: floats & Color APIs


  • Subject: Re: floats & Color APIs
  • From: John Stiles <email@hidden>
  • Date: Mon, 23 Oct 2006 12:14:06 -0700

Even QuickDraw used 16-bit shorts for representing color.

I think there are good reasons to support a higher range of color values than what an average monitor can display (256 unique shades of red, green or blue). A good printer can probably use 10-12 bits of color information per channel. Also, any time you are compositing images, having "extra" resolution above and beyond what you strictly need can make the final output look better. In a similar vein, audio editing tools usually work at 96KHz with 24- or 32-bit precision, even though that's much more precision than the ear can distinguish; this provides a lot of "slop" for the error that normally accumulates during composition.

For compact storage, you could certainly scale down the values if you want. Unless your customers demand exact color precision, it should be OK.


On Oct 23, 2006, at 11:47 AM, Eric Gorr wrote:

I'm just curious...

What is the reasoning behind moving to floats to represent color in Apple's Cocoa color APIs?

For example,

<http://developer.apple.com/documentation/Cocoa/Reference/ ApplicationKit/Classes/NSColor_Class/Reference/Reference.html#// apple_ref/occ/instm/NSColor/blueComponent>

Why wasn't 1 byte or even 2 bytes considered to be enough?
Were the reasons purely having to do with the speed of certain calculations?
Is there any reason not to just covert these numbers to single byte components for the purpose of file storage?



_______________________________________________
Do not post admin requests to the list. They will be ignored.
Cocoa-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
40blizzard.com


This email sent to email@hidden

_______________________________________________ Do not post admin requests to the list. They will be ignored. Cocoa-dev mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: This email sent to email@hidden
References: 
 >floats & Color APIs (From: Eric Gorr <email@hidden>)

  • Prev by Date: Re: some crash i can not explain.
  • Next by Date: Re: some crash i can not explain.
  • Previous by thread: floats & Color APIs
  • Next by thread: Re: floats & Color APIs
  • Index(es):
    • Date
    • Thread