NSImage or CIImage? Resolution problem

FROM : Bill So
DATE : Tue Aug 01 19:08:38 2006

Dear All,

I am a bit new to graphics programming.  I am trying to display an
image in a customer NSView.

The custom NSView is very simple.  It just displays an image in the
drawRect: method like below:
   sampleImage = [NSImage imageNamed:@"myimage.jpg"];
   [sampleImage compositeToPoint:NSMakePoint(0.0, 0.0)
operation:NSCompositeSourceOver];

sampleImage is an NSImage object.

sampleImage is from a JPG file which was obtained from my DC.  (And I
scaled it down to 800 x 600)

Below is the info. of the image in "Preview" app.

   File Name    myimage.jpg
   Document Type    JPEG Image
   File Size    218439 bytes
   Color Model    RGB
   Depth    8
   DPI Height    300
   DPI Width    300
   Orientation    1
   Pixel Height    600
   Pixel Width    800
   Profile Name    Camera RGB Profile

When I call [sampleImage size], the returned size is not 800 x 600.
It is 192 x 144.  How do I get NSImage use the exact pixel size? (i.e.
800 x 600)

http://developer.apple.com/documentation/Cocoa/Conceptual/CocoaDrawingGuide/Images/chapter_7_section_2.html#//apple_ref/doc/uid/TP40003290-CH208-SW2

Read the doc above but it just gives too little info for what I need to know...

Please kindly advise.

Thanks for helping.
Bill