Displaying a virtual object in a real-life scene

A system for displaying a virtual object in an imaged scene, the system comprising:

• a target apparatus, the target apparatus comprising a set of color target elements having known reflectance properties and at least one illumination target element having a plurality of known surface normals;
• an imaging device;
• a display device;
• and
• a computer system configured to carry out the steps of:
• a) causing the imaging device to obtain at least one image of the scene, the scene comprising the target apparatus;
• b) processing the at least one image of the scene to determine illumination and viewing conditions for the scene;
• c) processing the at least one image of the scene to determine measured colors for the color target elements;
• d) calculating color transformation parameters based on a comparison of the measured colors and the known reflectance properties of the color target elements, taking into account the determined illumination and viewing conditions;
• e) rendering the virtual object for the determined illumination and viewing conditions;
• f) aligning the rendered virtual object with the at least one image of the scene;
• g) applying a color transformation to the at least one image of the scene without applying the color transformation to the virtual object or applying an inverse color transformation to the virtual object without applying the inverse color transformation to the at least one image of the scene using the calculated color transformation parameters, wherein said color transformation transforms a first set of color attributes into a second set of color attributes such that the colors of the imaged scene and the colors of the rendered virtual object become directly comparable when displayed;
• and
• h) causing the display device to display an overlay of at least a portion of the rendered virtual object with at least a portion of the at least one image of the scene.

A computer program product comprising a non-volatile computer-readable medium on which program instructions are stored, wherein the program instructions which, when executed by at least one processor, cause the at least one processor to carry out the acts of:

• a) causing an imaging device to obtain at least one image a scene that comprises a sample object and a target apparatus, the target apparatus comprising a set of color target elements having known reflectance properties and at least one illumination target element having a plurality of known surface normals;
• b) processing the at least one image of the scene to determine illumination and viewing conditions for the scene;
• c) processing the at least one image of the scene to determine measured colors for the color target elements;
• d) calculating color transformation parameters based on a comparison of the measured colors and the known reflectance properties of the color target elements, taking into account the determined illumination and viewing conditions;
• e) rendering a virtual object for the determined illumination and viewing conditions;
• f) aligning the rendered virtual object with the sample object in the at least one image of the scene;
• g) applying a color transformation to the at least one image of the scene without applying the color transformation to the virtual object or applying an inverse color transformation to the virtual object without applying the inverse color transformation to the at least one image of the scene using the calculated color transformation parameters, wherein said color transformation transforms a first set of color attributes into a second set of color attributes such that the colors of the imaged scene and the colors of the rendered virtual object become directly comparable when displayed;
• and
• h) causing the display device to display at least a portion of the imaged sample object and at least a portion of the rendered virtual object simultaneously.