Systems and methods for text-based personalization of images

1. A computer-implemented method for placing a personalized text into an image to generate a natural text-rendered image comprising:

determining a location and region within the image where the personalized text is to be placed;

estimating a 3D geometry of a planar surface proximate to the location and region where the personalized text is to be placed;

receiving a personalized text string;

incorporating the personalized text string into the image to appear as if it is rendered onto the planar surface according to the estimated 3D geometry; and

outputting the natural text-rendered image;

wherein estimating the 3D geometry comprises:

determining a first convergent line set and a second convergent line set, wherein the lines within each set are deemed to be parallel in the image;

identifying a first vanishing point and a second vanishing point based at least in part upon the first and second convergent line sets;

determining a field of view of the image; and

determining a normal vector of the planar surface;

wherein incorporating the personalized text string into the image comprises rendering the personalized text string into the determined location and region within the image using a text mask, wherein the text mask is used to modulate one or more of texture, luminance, chrominance, and transparency of the image; and

wherein texture modulation comprises:

utilizing a priori a plurality of images to derive sets of resolution independent basis functions that describe real world textures under a range of illumination conditions and viewpoints;

fitting a texture within the determined location and region of a selected image to a linear combination of the basis functions to generate basis weights; and

modulating the basis weights in real time to impose a modulation on the texture in a natural way that creates readable text within the image.

2. The method according to claim 1 , wherein the determining step comprises:

receiving an initial location from a user via a graphical interface; and

automatically growing a region about this initial location based on a homogeneity property calculated proximate to the initial location.

3. The method according to claim 1 wherein the determining step comprises analyzing the image and automatically identifying one or more regions suitable for text placement using a homogeneity property calculated on the image pixels.

4. The method according to claim 1 , wherein receiving the personalized text string comprises accessing a database containing a plurality of records of personalized information and retrieving an appropriate record.

5. A computer implemented method for replacing an existing text string within an image with a personalized text string to generate a natural text-rendered image, comprising:

identifying a location and region within the image containing the existing text string to be replaced;

deriving selected features from the existing text string;

determining a 3D geometry of a surface upon which the existing text string has been rendered based on one or more of the selected features;

determining a normal vector of the surface;

erasing the existing text string;

receiving the personalized text string;

incorporating the personalized text string into the image to appear as if it is rendered onto the surface in place of the previously existing text string according to the estimated 3D geometry; and

outputting the natural text-rendered image;

wherein deriving the selected features comprises:

segmenting the existing text string from a background of the image; and

deriving the existing text string edges;

wherein a binary search algorithm is employed to establish a predetermined threshold based upon one that produces the largest number of connected components of the existing text string edges.

6. The method of claim 5 wherein the surface upon which the existing text string is rendered is assumed to be planar.

7. The method of claim 5 wherein identifying the location and region involves receiving user-entered vertices of a bounding polygon via a graphical user interface.

8. The method of claim 5 wherein identifying the location and region is performed automatically via analysis of the image.

9. The method of claim 5 , wherein determining the 3D geometry comprises:

identifying a horizontal convergent line set based at least in part on one or more text string edges;

identifying a vertical convergent line set based at least in part on one or more text string edges;

computing a first vanishing point and a second vanishing point based at least in part upon the horizontal and the vertical convergent line sets; and

determining a field of view of the image.

10. The method of claim 9 , wherein the convergent lines and vanishing points are calculated via Hough transforms.

11. The method of claim 5 , wherein erasing the existing text string comprises replacing each text pixel with an estimated background color.

12. The method of claim 5 wherein incorporating the personalized text string into the image further comprises calculating selected properties of the personalized text string to be similar to those of the previously existing text string.