• 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: NSImage question
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: NSImage question


  • Subject: Re: NSImage question
  • From: marcocoa <email@hidden>
  • Date: Fri, 25 May 2007 23:43:46 +0200

Nope, Preview does not display it any more correct than your app or XCode. I would guess the image is not at 72 dpi. You must be aware of the fact, that [image size] or [imageRep size] gives you the size it is *displayed* on the current device, i.e. the screen. The screen is assumed to be 72 dpi, so that makes 1.8" x 2.4" for your image (given its "size" of 129.6 x 172.8). You need to ask for [image pixelsWide] and [image pixelsHigh] to get the pixel dimensions which will be 180 x 240. Now you know that you have 180 pixels in 1.8 inches, that means, your original image had a resolution of 100 dpi.

In your case, try drawInRect:fromRect:operation:fraction: with the destination rect set to 180x240!

--marcocoa



Am 25.05.2007 um 08:32 schrieb Oscar Bascara:

Hi All,

Here is an NSImage puzzle.  I've got an image that I dragged from a
web page to the desktop.  The image gets saved as a jpg file, but it's
behaving strangely.  In Preview, the jpg file displays fine.  It has
size 180 x 240 (just as it is shown in the web page).  But then I try
to display the image in a program a usual way:

image = [NSImage imageNamed:@"image_file"];
[image compositeToPoint:point operation:NSCompositeSourceOver];

The image is drawn smaller for some reason.  Checking the image
representation size, I get 129.6 x 172.8.  Also, the image quality is
not as good, especially if I try rescaling it to 180 x 240.  Viewing
the image in the Xcode editor, by the way, also gives this weird,
smaller display size.  Somehow Preview knows how to display the image
correctly.

Any idea what is going on?

Oscar
_______________________________________________

Cocoa-dev mailing list (email@hidden)

Do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden



_______________________________________________

Cocoa-dev mailing list (email@hidden)

Do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden


  • Prev by Date: Re: Bindings and the selected object
  • Next by Date: Capture ARP packets
  • Previous by thread: Re: NSImage question
  • Next by thread: NSColor + Bindings
  • Index(es):
    • Date
    • Thread