Magnification and pinching of two-dimensional images

• US 20060078226A1
• Filed: 03/15/2005
• Published: 04/13/2006
• Est. Priority Date: 09/28/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhou, Mengyao
• Granted Patent: US 7,715,656 B2
• Time in Patent Office: Days
• US Class Current: 382/298
• CPC Class Codes: G06T 3/047 Fisheye or wide-angle transformations

Abstract

In one embodiment, an embedded device is provided which comprises a region of interest defining mechanism to define a region of interest (ROI) within an image. A transformation mechanism of the embedded device applies a nonlinear magnification or pinching transformation to the region of interest such that magnification or pinching within the region of interest varies from a greater amount at a focal point of the region of interest to a lesser amount at an outer border of the region of interest.

Claims

1. An embedded device, comprising:

a region of interest defining mechanism to define a region of interest within an image; and

a transformation mechanism to apply a nonlinear transformation resulting in magnification or pinching to the region of interest such that magnification or pinching within the region of interest varies from a greater amount at a focal point of the region of interest to a lesser amount at an outer border of the region of interest.

2. The embedded device according to claim 1, wherein the transformation mechanism applies the same nonlinear transformation function for magnification and pinching.

3. The embedded device of claim 2, further comprising a user interface coupled to the region of interest defining mechanism.

4. The embedded device of claim 2, further comprising a graphics entity, wherein the region of interest defining mechanism and the transformation mechanism are coupled to the graphics entity.

5. The embedded device of claim 4, further comprising:

a system bus;

a main memory; and

a display screen coupled to the graphics entity;

wherein the main memory and the graphics entity are coupled to the system bus.

6. The embedded device of claim 2, wherein the embedded device is a mobile telephone.

7. The embedded device of claim 6, wherein the mobile telephone includes a digital camera.

8. The embedded device of claim 1, wherein the nonlinear transformation uses only integer arithmetic.

9. The embedded device of claim 2, further comprising a user interface to receive user selections of parameters for the nonlinear magnification or pinching transformation, the parameters comprising a parameter determining whether the transformation produces magnification or pinching and a parameter determining a magnitude of the magnification or pinching.

10. The embedded device of claim 2, wherein when the region of interest defined by the region of interest defining mechanism is smaller in dimension than the image itself, pixels not within the region of interest are not transformed by the transformation mechanism.

11. The embedded device of claim 2, wherein the region of interest defining mechanism comprises an elliptical shape option to define an elliptical shape region of interest.

12. The embedded device of claim 2, wherein the region of interest defining mechanism comprises a circular shape option to define a circular shape region of interest.

13. The embedded device of claim 12, wherein the nonlinear magnification or pinching transformation performed by the transformation mechanism is represented by

$\begin{array}{c}{x}_{\mathrm{out}}=\{\begin{array}{c}{x}_o+\left(x_{\mathrm{in}}-x_o\right)·\end{array}\end{array}$

a ( - 1 ) m ⁡

[ 1 - ( x in - x o ) 2 + ( y in - y o ) 2 R 2 ] k for ⁢

 

( x in - x o ) 2 + ( y in - y o ) 2 ≤

R 2 x in otherwise  

( 1 ) y out = { y o + ( y in - y o ) ·

a ( - 1 ) m ⁡

[ 1 - ( x in - x o ) 2 + ( y in - y o ) 2 R 2 ] k for ⁢

 

( x in - x o ) 2 + ( y in - y o ) 2 ≤

R 2 y in otherwise  

( 2 )

wherein x_in and y_in are location coordinates for an input pixel within the region of interest, x_o and y_o are location coordinates for the center of the circular region of interest, R is the radius of the region of interest, x_out and y_out are location coordinates for an output pixel, a is a parameter indicative of the greater amount, m is a binary parameter indicative of whether the transformation produces magnification or pinching, and k is a parameter indicative of the degree of smoothness and continuity in an image transition region between areas of the region of interest influenced by the greater amount and areas of the region of interest influenced by the lesser amount.

14. The embedded device of claim 8, wherein the transformation mechanism performs calculations in a predetermined order of calculation so as to avoid integer overflow.

15. The embedded device of claim 1, wherein the transformation mechanism performs the magnification or pinching transformation in real time.

16. The embedded device of claim 1, wherein the transformation mechanism performs the magnification or pinching transformation in only one dimension within the region of interest.

17. The embedded device of claim 5, further comprising a display screen to display from the graphics entity a transformed image including both the region of interest with the magnification or pinching transformation and untransformed portions of the image.

18. The embedded device of claim 17, wherein the transformed image is a facial image with one or more transformed portions.

19. The embedded device of claim 10, wherein the device is adapted to perform two or more transformations on the image, the two or more transformations having the same or different parameters.

21. The machine-readable medium of claim 1, wherein the same nonlinear transformation function is applied for magnification and pinching.

22. The machine-readable medium of claim 21, wherein said applying is performed with integer arithmetic.

23. The machine-readable medium of claim 21, wherein the tasks further comprise allowing a user to select, directly or indirectly, parameters for the nonlinear magnification or pinching transformation that determine whether the transformation produces magnification or pinching and a magnitude or power of the magnification or pinching.

24. The machine-readable medium of claim 21, wherein the region of interest within the image is smaller in dimension than the image itself and pixels not within the region of interest are not transformed.

25. The machine-readable medium of claim 21, wherein the region of interest is elliptical in shape.

26. The machine-readable medium of claim 21, wherein the region of interest is circular in shape.

27. The machine-readable medium of claim 26, wherein the nonlinear magnification or pinching transformation is represented by Equations (1) and (2) below:

$\begin{array}{cc}{x}_{\mathrm{out}}=\{\begin{array}{ccc}{x}_o+\left(x_{\mathrm{in}}-x_o\right)·<br><br>a^{{{\left(-1\right)}^m<br><br>\left[1-\frac{{\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2}{R^2}\right]}^k}& \mathrm{for}<br><br>\text{\hspace{1em}<br><br>}& {\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2\le <br><br>R^2\\ x_{\mathrm{in}}& \mathrm{otherwise}& \text{\hspace{1em}<br><br>}\end{array}& \left(1\right)\\ y_{\mathrm{out}}=\{\begin{array}{ccc}{y}_o+\left(y_{\mathrm{in}}-y_o\right)·<br><br>a^{{{\left(-1\right)}^m<br><br>\left[1-\frac{{\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2}{R^2}\right]}^k}& \mathrm{for}<br><br>\text{\hspace{1em}<br><br>}& {\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2\le <br><br>R^2\\ y_{\mathrm{in}}& \mathrm{otherwise}& \text{\hspace{1em}<br><br>}\end{array}& \left(2\right)\end{array}$

wherein x_in, and y_in are location coordinates for an input pixel within the region of interest, x_o and y_o are location coordinates for the center of the circular region of interest, R is the radius of the region of interest, x_out and y_out are location coordinates for an output pixel, a is a parameter indicative of the greater amount, m is a binary parameter indicative of whether the transformation produces magnification or pinching, and k is a parameter indicative of the degree of smoothness and continuity in an image transition region between areas of the region of interest influenced by the greater amount and areas of the region of interest influenced by the lesser amount.

28. The machine-readable medium of claim 22, further interoperable with a machine to perform said applying in a predetermined order of calculation so as to avoid integer overflow.

29. The machine-readable medium of claim 21, wherein the nonlinear transformation is performed in real time.

30. The machine-readable medium of claim 21, wherein the machine is an embedded device.

31. The machine-readable medium of claim 30, wherein the embedded device is a mobile telephone.

32. The machine-readable medium of claim 31, wherein the mobile telephone includes a digital camera.

33. The machine-readable medium of claim 31, wherein the mobile telephone has an integer microprocessor.

20. A machine-readable medium interoperable with a machine to:

define a region of interest within an image; and

apply a nonlinear magnification or pinching transformation to the region of interest such that magnification or pinching within the region of interest varies from a greater amount at a focal point of the region of interest to a lesser amount at an outer border of the region of interest.

34. A mobile telephone, comprising:

a receiver/transmitter assembly;

a microprocessor;

a region of interest defining mechanism coupled to the microprocessor to define a region of interest within an image; and

a transformation mechanism coupled to the microprocessor to apply a nonlinear magnification or pinching transformation function to the region of interest such that magnification or pinching within the region of interest varies from a greater amount at a focal point of the region of interest to a lesser amount at an outer border of the region of interest.

35. The mobile telephone of claim 34, wherein the transformation mechanism uses the same nonlinear transformation function for magnification and pinching.

36. The mobile telephone of claim 35, wherein the microprocessor is an integer microprocessor.

37. The mobile telephone of claim 35, wherein the transformation mechanism applies the nonlinear transformation using only integer arithmetic.

38. Apparatus comprising:

means for defining a region of interest within an image; and

means for applying a nonlinear magnification or pinching transformation to the region of interest such that magnification or pinching within the region of interest varies from a greater amount at a focal point of the region of interest to a lesser amount at an outer border of the region of interest.

39. The apparatus of claim 38, wherein the defining means uses the same nonlinear transformation function for magnification and pinching.

40. The system of claim 39, wherein the applying means includes means for facilitating integer arithmetic.

41. The system of claim 39, further comprising means for interfacing with a user coupled to the defining means to define the region of interest.

42. The system of claim 39, wherein the region of interest is circular.

43. The system of claim 42, wherein the nonlinear magnification or pinching transformation is represented by Equations (1) and (2) below:

$\begin{array}{cc}{x}_{\mathrm{out}}=\{\begin{array}{ccc}{x}_o+\left(x_{\mathrm{in}}-x_o\right)·<br><br>a^{{{\left(-1\right)}^m<br><br>\left[1-\frac{{\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2}{R^2}\right]}^k}& \mathrm{for}<br><br>\text{\hspace{1em}<br><br>}& {\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2\le <br><br>R^2\\ x_{\mathrm{in}}& \mathrm{otherwise}& \text{\hspace{1em}<br><br>}\end{array}& \left(1\right)\\ y_{\mathrm{out}}=\{\begin{array}{ccc}{y}_o+\left(y_{\mathrm{in}}-y_o\right)·<br><br>a^{{{\left(-1\right)}^m<br><br>\left[1-\frac{{\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2}{R^2}\right]}^k}& \mathrm{for}<br><br>\text{\hspace{1em}<br><br>}& {\left(x_{\mathrm{in}}-x_o\right)}^2+{\left(y_{\mathrm{in}}-y_o\right)}^2\le <br><br>R^2\\ y_{\mathrm{in}}& \mathrm{otherwise}& \text{\hspace{1em}<br><br>}\end{array}& \left(2\right)\end{array}$

wherein x_in and y_in are location coordinates for an input pixel within the region of interest, x_o and y_o are location coordinates for the center of the circular region of interest, R is the radius of the region of interest, x_out and y_out are location coordinates for an output pixel, a is a parameter indicative of the greater amount, m is a binary parameter indicative of whether the transformation produces magnification or pinching, and k is a parameter indicative of the degree of smoothness and continuity in an image transition region between areas of the region of interest influenced by the greater amount and areas of the region of interest influenced by the lesser amount.

44. The system of claim 39, wherein the region of interest is elliptical.