Image data processing using depth image data for realistic scene representation

1. A method of producing a computer display image, the method comprising:

obtaining a sharp image of a scene;

producing a blur image of the scene; and

generating a composited blend image of the sharp and blur images and z-dimension image data;

producing a sequence of images generated as is the composited blend image to provide a rack focus effect that appears to shift image focus between foreground of the scene and background of the scene;

wherein the composited blend image has depth of field information when rendered for presentation on a display device along with the sequence of images.

2. A method as defined in claim 1 , wherein the blur image comprises pixel-shifted color channel image data of the sharp image.

3. A method as defined in claim 2 , wherein the z-dimension image data comprises truncated z pixel information that specifies pixel location data for the scene.

4. A method as defined in claim 3 , wherein the truncated z pixel information comprises a predetermined number of the most significant bits for each pixel of the z-dimension image data.

5. A method as defined in claim 1 , wherein each image of the sequence is produced by:

producing an alpha channel RGBA image by compositing the sharp image of the scene with a blur image of the scene with z-dimension image data;

producing an inverted alpha channel RGBA image by compositing the sharp image of the scene with a blur image of the scene with inverted z-dimension image data; and

blending the inverted alpha channel RGBA image with the alpha channel RGBA image.

6. A method as defined in claim 1 , further comprising changing the blur image hue to a desired color value and using the changed blur image as the source of the z-dimension image data to produce the composited blend image.

7. A method as defined in claim 6 , wherein the blur image hue is changed to a blue color value to produce an alpha channel RGBA image with an atmospheric effect.

8. A method as defined in claim 6 , wherein changing the blur image comprises:

copying red channel data of the blur image onto green channel data of the blur image and copying the red channel data of the blur image onto blue channel data of the blur image to thereby produce a black-and-white blur image;

storing the black-and-white blur image in a z-buffer temporary data store of the scene; and

combining the data of the blur image in the z-buffer temporary data store with the sharp image to produce the composited blend image.

9. A method as defined in claim 1 , wherein the composited blend image is an RGBA image.

10. A method as defined in claim 1 , wherein generating the composited blend image of the sharp and blur images and z-dimension image data implements an alpha channel blending process that utilizes the z-dimension image.

11. A method for processing video image data for display during interactive game play, comprising:

during a game play session, processing one or more images of the game play session to adjust scene representation of objects at a first distance relative to objects at a second distance, during the game play session, performing the following operations,

(a) generating a sharp image for a scene;

(b) producing a blur image of the scene; and

(c) generating a composited blend image of the sharp and blur images using data from z-dimension image data, where the composited blend image has depth of field information provided by the z-dimension image data; and

(d) rendering the scene for display during the interactive game play; and

(c) repeating (a)–(d) for two or more images during the game play session, and the two or more images providing a rack focus effect that appears to shift image focus between foreground of the scene and background of the scene.

12. A method for processing video image data for display during interactive game play as recited in claim 11 , wherein the objects at the first distance are closer objects having a shaper representation and objects at the second distance are further objects having a more blurred representation.

13. A method for processing video image data for display during interactive game play as recited in claim 12 , further comprising,

determining continuously during game play when objects are in the first distance or the second distance and adjusting the representation of sharper or blurred depending on location or movement of the objects.

14. A method for processing video image data for display during interactive game play as recited in claim 13 , wherein the adjusting of the representation of sharper or blurred is gradual as objects move between the first distance and the second distance.

15. A computer implemented method embodiment on a computer readable media, the computer implemented method being for processing video image data for display during interactive game play, comprising:

during a game play session, processing one or more images of the game play session to adjust scene representation of objects at a first distance relative to objects at a second distance, during the game play session, performing the following operations,

(a) generating a sharp image for a scene;

(b) producing a blur image of the scene; and

(c) generating a composited blend image of the sharp and blur images using data from z-dimension image data, the composited blend image has depth of field information provided by the z-dimension image data, and the generating of the composited blend image of the sharp and blur images and z-dimens ion image data implements an alpha channel blending process that utilizes the z-dimension image; and

(d) rendering the scene for display during the interactive game play; and

(c) repeating (a)–(d) for two or more images during the game play session, and the two or more images providing a rack focus effect that appears to shift image focus between foreground of the scene and background of the scene.

16. A method for processing video image data for display during interactive game play as recited in claim 15 , wherein the objects at the first distance are closer objects having a shaper representation and objects at the second distance are further objects having a more blurred representation.

17. A method for processing video image data for display during interactive game play as recited in claim 16 , further comprising,

determining continuously during game play when objects are in the first distance or the second distance and adjusting the representation of sharper or blurred depending on location or movement of the objects.

18. A method for processing video image data for display during interactive game play as recited in claim 17 , wherein the adjusting of the representation of sharper or blurred is gradual as objects move between the first distance and the second distance.